{"schema_version":"1.0.0","title":"WTC reconstruction fidelity assumptions and evidence register","audit_date":"2026-09-11","purpose":"Durable, machine-readable consolidation of exterior, interior, and application-wide audits.","validation_scope":"Current coverage and limitations reconciled with the September 11 release review and latest core/stair source records. Earlier record-level verification dates are retained. Fresh release checks cover geometry/state integration and a bounded browser sample; they do not certify historical completeness or whole-tower responsiveness.","current_implementation_state":{"status":"integrated_locally","code_status":"geometry_and_state_checks_passed_with_browser_limits","post_integration_checks_required":true,"warning":"Original-plan educational reconstruction, not a complete 1:1 September 2001 model. Whole-tower responsiveness still needs a target-device check. The onset sequence does not solve structural or thermal response.","render_revision":"accuracy-notes-2026-09-11","purpose":"Use observations and published calculations to provide the most representative explanatory reconstruction; retain source/inference distinctions in the evidence records.","pending_checks":["Check whole-tower and onset responsiveness on the intended release browser/device."]},"source_conventions":{"page_numbers":"Printed report pages unless explicitly stated otherwise; arrays can contain page ranges.","figure_ids":"Report figure/table labels, not PDF page indices.","primary_vs_audit":"Primary reports support historical/model claims. Audit sources support code behavior and verification witnesses.","empty_printed_pages":"The source is an unpaginated code audit or drawing transcription; no printed page is invented.","evidence_categories":"Categories identify provenance, not a single confidence score.","synthetic_ids":"Viewer panel/member IDs are not fabrication marks unless separately established.","verification_dates":"The register update date is not a new independent source audit of every record. Each record retains its own verification date and method."},"status_policy":{"current_code_status":"Record-level integrated status; source limits remain even when geometry/state checks pass.","post_integration_verified":"False is not a failing test; it means this record has not been revalidated against final integrated code.","permitted_status_updates":["verified_against_integrated_code","partly_addressed_with_recorded_limit","unresolved_source_limit","regression_detected"],"required_update_fields":["verification_date","verification_method","result","artifact_or_test_reference","remaining_limitation"]},"sources":{"FEMA403-CH2":{"document":"FEMA 403, World Trade Center Building Performance Study, Chapter 2","publication":"May 2002","local_path":"/Users/theair/wtc-explainer/sources/fema403/fema403_ch2.pdf","official_url":"https://www.fema.gov/pdf/library/fema403_ch2.pdf","source_kind":"primary_report"},"NCSTAR1-1":{"document":"NIST NCSTAR 1-1, Design, Construction, and Maintenance of Structural and Life Safety Systems","local_path":"/Users/theair/wtc-explainer/sources/NCSTAR1-1.pdf","official_url":"https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=101332","source_kind":"primary_report"},"NCSTAR1-2":{"document":"NIST NCSTAR 1-2, Baseline Structural Performance and Aircraft Impact Damage Analysis","local_path":"/Users/theair/wtc-explainer/sources/NCSTAR1-2.pdf","official_url":"https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=101012","source_kind":"primary_report"},"NCSTAR1-2A":{"document":"NIST NCSTAR 1-2A, Reference Structural Models and Baseline Performance Analysis","local_path":"/Users/theair/wtc-explainer/sources/NCSTAR1-2A.pdf","official_url":"https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=101013","source_kind":"primary_report"},"NCSTAR1-3":{"document":"NIST NCSTAR 1-3, Mechanical and Metallurgical Analysis of Structural Steel","official_url":"https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=101016","source_kind":"primary_report","availability_note":"Final report independently retrieved on 2026-09-07; see NCSTAR1-3_final for checksum. Earlier audit citations retain their stated review scope.","local_path":"/Users/theair/wtc-explainer/sources/NCSTAR1-3_final.pdf"},"NCSTAR1-6":{"document":"NIST NCSTAR 1-6, Structural Fire Response and Probable Collapse Sequence","local_path":"/Users/theair/wtc-explainer/sources/NCSTAR1-6.pdf","source_kind":"primary_report_draft","edition_note":"The locally collected file is the Draft for Public Comment according to SOURCES.md. Retain edition with page citations; do not silently represent it as the final edition."},"NCSTAR1-6C":{"document":"NIST NCSTAR 1-6C, Component, Connection, and Subsystem Structural Analysis","local_path":"/Users/theair/wtc-explainer/sources/NCSTAR1-6C.pdf","official_url":"https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=101043","source_kind":"primary_report"},"LERA-HEIGHTS":{"document":"LERA floor-height transcription, 2002","local_path":"sources/LERA - PLANS-022102/floor_heights.txt","referenced_drawings":["Port Authority A-AB-201","Port Authority A-AB-301"],"source_kind":"drawing_transcription","edition_note":"All 220 story heights match this transcription. Roof elevations, floor-1 reference and source schedule bands remain distinct datums."},"AUDIT-EXT":{"document":"Exterior fidelity audit","local_path":"/Users/theair/wtc-explainer/analysis/exterior_fidelity_audit.md","sha256":"790ff6bdcd413fdfb76325075cb672e6cd3e96ac7623b74a7a9bcdb93491d0f8","source_kind":"source_and_code_audit"},"AUDIT-INT":{"document":"Interior fidelity and cross-view damage audit","local_path":"/Users/theair/wtc-explainer/analysis/interior_fidelity_audit.md","sha256":"eb3f14800acfa8d1edba88fa04c0285d96d96388aec681e54ee025284e4c10db","source_kind":"source_and_code_audit","prior_snapshot_sha256":"5079541fa44a288b322269c727ac8a0286dc445f32b850f71f0afb97b9acff3b","revision_note":"Includes the appended Follow-up geometry review during implementation. Earlier code-state observations remain historical snapshots; follow-up CPU checks do not certify final integration."},"AUDIT-APP":{"document":"Application-wide damage-state audit","local_path":"/Users/theair/wtc-explainer/analysis/view_consistency_audit.md","sha256":"2e9132822bd0a5b1b19d337bf35199821b4d550ed19b56608e3480d1ec6643ee","source_kind":"code_audit","validation_note":"This auditor did not independently verify primary-source transcription."},"NCSTAR1-3Cv1":{"title":"Damage and Failure Modes of Structural Steel Components, NIST NCSTAR 1-3C, Volume I","local_path":"/Users/theair/wtc-explainer/sources/NCSTAR1-3Cv1.pdf","official_url":"https://nvlpubs.nist.gov/nistpubs/Legacy/NCSTAR/ncstar1-3cv1.pdf","sha256":"2a5f7edf120d98c7e15a77d7aa1768c6a14cbdde198e622fd70402a499767124","page_warning":"The archive PDF has nonsequential scanned page ordering. Use printed page labels and the explicit PDF page numbers in each record.","document":"Damage and Failure Modes of Structural Steel Components, NIST NCSTAR 1-3C, Volume I","source_kind":"primary_report"},"NCSTAR1-2B_final_appendixes":{"document":"NCSTAR1-2B final appendixes","official_url":"https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=909015","local_path":"/Users/theair/wtc-explainer/sources/NCSTAR1-2B_final_appendixes.pdf","sha256":"a4453119823f04f3d4e1fabfb228eb05dac71ffc7eacf0385c1a0774d61f1925","source_kind":"primary_report_final","retrieval_date":"2026-09-07"},"NCSTAR1-1A_final":{"document":"NCSTAR1-1A final","official_url":"https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=101000","local_path":"/Users/theair/wtc-explainer/sources/NCSTAR1-1A_final.pdf","sha256":"5765450d35e4230556db1deb7e897e390eeec54eed87a91b0ba92c2b07453740","source_kind":"primary_report_final","retrieval_date":"2026-09-07"},"NCSTAR1-2B_final_ch1-8":{"document":"NCSTAR1-2B final ch1-8","official_url":"https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=101428","local_path":"/Users/theair/wtc-explainer/sources/NCSTAR1-2B_final_ch1-8.pdf","sha256":"0fa8b051fff1d225b502df5c103917f0ad443dbdcc12dde5c68f38888c770124","source_kind":"primary_report_final","retrieval_date":"2026-09-07"},"NCSTAR1-3A_final":{"document":"NCSTAR1-3A final","official_url":"https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=101017","local_path":"/Users/theair/wtc-explainer/sources/NCSTAR1-3A_final.pdf","sha256":"edc7be70ae133367efa56f6ad583e430ab6317eecee125834417a06aea864c1c","source_kind":"primary_report_final","retrieval_date":"2026-09-07"},"NCSTAR1-3B_final":{"document":"NCSTAR1-3B final","official_url":"https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=101430","local_path":"/Users/theair/wtc-explainer/sources/NCSTAR1-3B_final.pdf","sha256":"71cd9614d2f127464b6e278d2a28b414b303eda403448fc7f8e34751c67b906f","source_kind":"primary_report_final","retrieval_date":"2026-09-07"},"NCSTAR1-2B_final_ch9-11":{"document":"NCSTAR1-2B final ch9-11","official_url":"https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=101015","local_path":"/Users/theair/wtc-explainer/sources/NCSTAR1-2B_final_ch9-11.pdf","sha256":"ed3d22b58e00c24e4e15e4884e9e55b8cabaa9f8e870f0f85979a4018c1ad185","source_kind":"primary_report_final","retrieval_date":"2026-09-07"},"NCSTAR1-3_final":{"document":"NCSTAR1-3 final","official_url":"https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=101016","local_path":"/Users/theair/wtc-explainer/sources/NCSTAR1-3_final.pdf","sha256":"dc692eb05b2565c5309829311aef932b4054888624a8be810907d0144d55031d","source_kind":"primary_report_final","retrieval_date":"2026-09-07"},"NCSTAR1-5A_final_ch1-8":{"document":"NCSTAR1-5A final ch1-8","official_url":"https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=101356","local_path":"/Users/theair/wtc-explainer/sources/NCSTAR1-5A_final_ch1-8.pdf","sha256":"fa72da7d03379d22696c3a4153ea91264f4fb816c15af2b9b1d0fa4124ec10aa","source_kind":"primary_report_final","retrieval_date":"2026-09-07"},"NCSTAR1-5A_final_ch9-appC":{"document":"NCSTAR1-5A final ch9-appC","official_url":"https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=101030","local_path":"/Users/theair/wtc-explainer/sources/NCSTAR1-5A_final_ch9-appC.pdf","sha256":"b18312794ebf158fc9d060902ed6e3d7e53c7ac5a55fb1c838932d3eb1dd4b88","source_kind":"primary_report_final","retrieval_date":"2026-09-07"},"NCSTAR1-1A_final_appendixes_A-B":{"title":"NCSTAR1-1A final appendixes A-B","official_url":"https://nvlpubs.nist.gov/nistpubs/Legacy/NCSTAR/ncstar1-1av2.pdf","local_path":"sources/NCSTAR1-1A_final_appendixes_A-B.pdf","sha256":"edc6de0499c2977893e12aeb4164737641e3dcbfaaab4dadf74a10129a6e8f94"},"NCSTAR1-1A_final_appendices_C-G":{"title":"NCSTAR1-1A final appendices C-G","official_url":"https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=101334","local_path":"sources/NCSTAR1-1A_final_appendices_C-G.pdf","sha256":"1950cea9b264653e6348fe6d21a5e61a3935886ac43b67cbb475cb3663600886"},"NCSTAR1-6D_final":{"title":"NCSTAR1-6D final","official_url":"https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=101366","local_path":"sources/NCSTAR1-6D_final.pdf","sha256":"0d2a155fc820c83e4bc7df32a6da098261eb2e7f8d1358abd00d11c12bd6c9ff"},"NCSTAR1-5G_final":{"title":"NCSTAR1-5G final","official_url":"https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=101039","local_path":"sources/NCSTAR1-5G_final.pdf","sha256":"474c5bf5d0679c1ce2308e0f559869a776f5f968bba2c80c307ea1b085e6d1a3"},"AISC-DG15-2002":{"title":"AISC Design Guide15, historical shapes1953\u20131970","official_url":"https://16streets.com/39-B/PDF%20files/AISC%20Rehabilitation%20and%20Retrofit%20Guide%20-%20Reference%20for%20Historic%20Shapes%20and%20Specifications%201.pdf","note":"Original AISC publication on third-party mirror; Table2.2.1 p28. Used only for exact matching historical sizes."},"LERA-WORKPOINTS":{"document":"LERA WTC - Roof Truss.xls, coordinate worksheet","local_path":"sources/LERA - PLANS-022102/tvmast/WTC - Roof Truss.xls","source_kind":"drawing_transcription","edition_note":"Numeric workpoints supplied for 97\u2013100 and separately for 107, 108, 109 and 110; no direct workpoints supplied for 1\u201396 or 101\u2013106."},"LERA-ARCHITECTURAL":{"document":"Port Authority Tower A architectural drawings, LERA collection","local_path":"sources/LERA - PLANS-022102/","source_kind":"original_drawings","edition_note":"Original design drawings; later alterations and September 2001 conditions require separate evidence."},"PANYNJ-12673":{"document":"Port Authority public release 12673, original Tower B architectural drawings","official_url":"https://pacorpredevblobstorage.blob.core.windows.net/board-documents/uploads/documents/freedom-of-information/foi-fulfilled-requests/12673-WTC.pdf","local_path":"sources/PANYNJ-12673-WTC.pdf","source_kind":"original_drawings","edition_note":"Drawing numbers identify original sheets; PDF pages are not printed report pages."},"NCSTAR1-7":{"document":"NIST NCSTAR 1-7, Occupant Behavior, Egress, and Emergency Communications","local_path":"sources/NCSTAR1-7.pdf","public_url":"https://archive.org/details/occupantbehavior17aver","source_kind":"primary_report"}},"records":[{"id":"EVID-001","priority":"P1","title":"Keep source evidence separate from model identity and display inference","evidence_category":["observed_schematic","simulation_result","geometric_inference"],"checked_sources":[{"source_id":"NCSTAR1-2","printed_pages":["187-189","209-211","232-234","254-256","275-277","288"],"figures":["7-12","7-26","7-42","7-56","7-72"],"sections":[]},{"source_id":"AUDIT-INT","printed_pages":[],"figures":[],"sections":["Evidence boundary"]}],"supported_claim":"Published observations, calculated damage footprints, synthetic model IDs, and intersection intervals are different kinds of information.","limitation":"No complete set of historically identified damaged interior trusses or measured fracture surfaces has been established.","recommended_correction":"Store source evidence, model identity, simulation case, display rule, and historical-identity status in separate fields; avoid any unsupported complete-fidelity claim.","check_method":{"kind":"report_text_and_figure_review","reported_in":["AUDIT-EXT","AUDIT-INT"],"consolidation":"Synthesis of documented auditor checks."},"audit_status":"source_boundary_confirmed","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/floor-model.js","/Users/theair/wtc-explainer/site/js/damage-map.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"Exports and inspectors separate FEMA panel identities, NIST cases, model span IDs, and inferred intervals. No historical individual-truss confirmation is asserted.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"No complete set of historically identified damaged interior trusses or measured fracture surfaces has been established."}},{"id":"EXT-001","priority":"P2","title":"FEMA contour fidelity and numerical precision","evidence_category":["observed_schematic","geometric_inference"],"checked_sources":[{"source_id":"FEMA403-CH2","printed_pages":["2-18","2-30"],"figures":["2-16","2-27"],"sections":[]},{"source_id":"AUDIT-EXT","printed_pages":[],"figures":[],"sections":["Three independent checks"]}],"supported_claim":"All 134 extracted regions triangulate to outer area minus window-hole area; the audit found no mismatched region at 1e-5 tolerance.","limitation":"Source center anchors retain drafting residuals equivalent to about 1.674 inches for WTC1 and 1.605 inches for WTC2. This is not a survey accuracy statement.","recommended_correction":"Preserve raw PDF paths, calibration and source hashes; label contours schematic and document any normalization to nominal member dimensions.","check_method":{"kind":"independent_vector_and_triangulation_check","reported_in":["AUDIT-EXT"],"quantitative_result":{"regions":134,"aggregate_area_error_below":6e-13,"units":"square feet times fractional story","region_tolerance":1e-05}},"audit_status":"geometry_check_passed_source_accuracy_limited","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/analysis/extract_exterior_panel_trace.py","/Users/theair/wtc-explainer/analysis/exterior_panel_trace.json","/Users/theair/wtc-explainer/site/js/exterior-panels.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"The archived FEMA baseline contains 134 regions verified by outer-minus-hole area and projection tests. The current renderer additionally applies panel-specific later NIST observations; see EXT-014. FEMA fidelity alone does not certify NIST agreement.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"Source center anchors retain drafting residuals equivalent to about 1.674 inches for WTC1 and 1.605 inches for WTC2. This is not a survey accuracy statement. Later NIST schematics revise some boundaries. Local corrections do not constitute a complete measured 3D damage survey."}},{"id":"EXT-002","priority":"P1","title":"Estimated and insufficient-information regions","evidence_category":["estimated","insufficient_information"],"checked_sources":[{"source_id":"FEMA403-CH2","printed_pages":["2-18","2-30"],"figures":["2-16","2-27"],"sections":[]},{"source_id":"AUDIT-EXT","printed_pages":[],"figures":[],"sections":["P1: Unknown source regions"]}],"supported_claim":"FEMA estimates WTC1 columns 111-115 at level 98 and WTC2 columns 413-418 at levels 81-82; it lacks sufficient detail for WTC2 columns 408-411 at levels 83-84.","limitation":"A schematic placeholder or blank damage entry in an obscured region does not prove that steel was intact.","recommended_correction":"Retain localized observed, estimated, and insufficient-information states separately and expose their distinction visually and in member records.","check_method":{"kind":"source_note_visual_review","reported_in":["AUDIT-EXT"]},"audit_status":"source_limits_confirmed","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/data/exterior_panels.json","/Users/theair/wtc-explainer/site/js/exterior-panels.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"Localized estimated and insufficient-information records added; yellow/violet dashed annotations mark source uncertainty. Annotation margins are display bounds only.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"A schematic placeholder or blank damage entry in an obscured region does not prove that steel was intact."}},{"id":"EXT-003","priority":"P1","title":"Aggregate severed columns do not define fracture intervals","evidence_category":["observed_summary","observed_schematic"],"checked_sources":[{"source_id":"NCSTAR1-2","printed_pages":["302-304"],"figures":[],"sections":["Findings16-17"]},{"source_id":"FEMA403-CH2","printed_pages":["2-15","2-18"],"figures":["2-16"],"sections":[]},{"source_id":"AUDIT-EXT","printed_pages":[],"figures":[],"sections":[]}],"supported_claim":"NIST's WTC1 observed aggregate lists columns 112-144 and 151 severed, 145-148 heavily damaged, 149-150 moderately damaged.","limitation":"The unique-column list does not assign the same state to every story or every panel along each column.","recommended_correction":"Use explicit source profiles or documented member intervals for geometry; retain aggregate findings as separate summaries instead of rectangular deletion masks.","check_method":{"kind":"report_text_crosscheck","reported_in":["AUDIT-EXT"]},"audit_status":"source_boundary_confirmed","current_code_status":"verified_against_integrated_code","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/data/damage_state.json","/Users/theair/wtc-explainer/site/js/floor-model.js","/Users/theair/wtc-explainer/site/js/scene.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"Aggregate NIST unique-column totals do not create multi-floor removal masks.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"The unique-column list does not assign the same state to every story or every panel along each column."}},{"id":"EXT-004","priority":"P1","title":"WTC1 south ejected panel retains its fractional end stories","evidence_category":["observed_summary","model_input","geometric_registration"],"checked_sources":[{"source_id":"NCSTAR1-5A_final_ch1-8","printed_pages":["75\u201376"],"figures":["6-16"]}],"supported_claim":"C329\u2013331 are clipped only over registered levels93.5\u201396.5, preserving the lower half of story93 and upper half of story96. Spandrels94/95/96 are absent. Floor, stack and tower share these extents.","limitation":"NIST tentatively identifies this panel through smoke. Middle-of-story registration follows the written description; exact splice heights and three-dimensional fracture paths are unresolved.","recommended_correction":"C329\u2013331 are clipped only over registered levels93.5\u201396.5, preserving the lower half of story93 and upper half of story96. Spandrels94/95/96 are absent. Floor, stack and tower share these extents.","check_method":{"kind":"source_matrix_visual_review_and_code_comparison","reported_in":["AUDIT-EXT","AUDIT-INT"],"witness":"At the audit snapshot, column-story keys 93-95 removed spandrels 94-96 in Tower but 93-95 in floor views."},"audit_status":"discrepancy_present_in_audited_snapshot","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/data/damage_state.json","/Users/theair/wtc-explainer/site/js/scene.js","/Users/theair/wtc-explainer/site/js/floor-model.js"],"implementation_followup_snapshot":{"source_id":"AUDIT-INT","section":"Follow-up geometry review during implementation","observation":"The later interior CPU check found WTC 1 south spandrel gaps at floors 94, 95, and 96 spanning world x = -5 to +5 ft, with column intervals kept separate and splice tests applied at each individual joint. Final integrated behavior remains to be rechecked.","final_integration_verified":false},"verification":{"verification_date":"2026-09-07","verification_method":"Independent source readback and current production geometry/state checks; exact test scope and source registrations are linked.","result":"C329\u2013331 are clipped only over registered levels93.5\u201396.5, preserving the lower half of story93 and upper half of story96. Spandrels94/95/96 are absent. Floor, stack and tower share these extents.","artifact_or_test_reference":["analysis/structural-expansion-v6/exterior/production-exterior-verification.json","site/data/damage_state.json"],"remaining_limitation":"NIST tentatively identifies this panel through smoke. Middle-of-story registration follows the written description; exact splice heights and three-dimensional fracture paths are unresolved."}},{"id":"EXT-005","priority":"P1","title":"WTC 2 north exit damage is localized","evidence_category":["observed_summary","insufficient_information"],"checked_sources":[{"source_id":"NCSTAR1-2","printed_pages":["279"],"figures":["7-75"],"sections":[]},{"source_id":"AUDIT-EXT","printed_pages":[],"figures":[],"sections":[]}],"supported_claim":"NIST identifies six-foot severances of columns 253 and 254, a retained non-load-bearing outer web at 254, and failed connections at 257 and 258.","limitation":"The six-foot length and column/floor relationships are sourced. Gap translation (\u00b11 ft), web bow and connection-gap magnitudes remain representative. NCSTAR 1-3C prose identifies 254/255, conflicting with corroborated 253/254 labels in NCSTAR 1-2 and 1-5A. Columns 252, 255 and 259 remain intact; the possible bow at 256 is unresolved.","recommended_correction":"Columns 253 and 254 now show local six-foot severance; 254 retains its outer web and short side-plate lips. Columns 257 and 258 retain steel with floor 81 disconnections and slight outward bends.","check_method":{"kind":"source_figure_visual_review","reported_in":["AUDIT-EXT"]},"audit_status":"source_limit_confirmed_broad_removal_disabled_at_audit","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/exterior-exit-fragments.js","/Users/theair/wtc-explainer/site/data/exterior_fragments.json"],"verification":{"verification_date":"2026-09-07","verification_method":"Primary-source review and registered source overlays where applicable; production geometry/state tests; targeted live browser inspection. Final integration: 253 checks passed, with no failures.","result":"Columns 253 and 254 now show local six-foot severance; 254 retains its outer web and short side-plate lips. Columns 257 and 258 retain steel with floor 81 disconnections and slight outward bends.","artifact_or_test_reference":["tools/check_exterior_supplements.mjs","site/data/exterior_fragments.json","analysis/exterior-gap-review/REVIEW.md","analysis/view-integration-verification.json","analysis/evidence-expansion-browser-checks.json"],"remaining_limitation":"The six-foot length and column/floor relationships are sourced. Gap translation (\u00b11 ft), web bow and connection-gap magnitudes remain representative. NCSTAR 1-3C prose identifies 254/255, conflicting with corroborated 253/254 labels in NCSTAR 1-2 and 1-5A. Columns 252, 255 and 259 remain intact; the possible bow at 256 is unresolved."}},{"id":"EVID-002","priority":"P1","title":"Initial and refined NIST cases are distinct","evidence_category":["model_input","simulation_result"],"checked_sources":[{"source_id":"NCSTAR1-6C","printed_pages":["95"],"figures":[],"sections":["5.5.6"]},{"source_id":"AUDIT-INT","printed_pages":[],"figures":[],"sections":["Evidence boundary"]},{"source_id":"AUDIT-EXT","printed_pages":[],"figures":[],"sections":["Constraints that remain necessary"]}],"supported_claim":"NCSTAR1-6C distinguishes initial Ai/Bi/Ci/Di floor-model conditions from refined A/B/C/D conditions and states the refined cases were not used in that full-floor model.","limitation":"Equality of exterior damage between certain initial floor-model inputs does not establish universal equality across all global impact simulations.","recommended_correction":"Retain exact case and analysis stage with each dataset and citation; do not combine initial and refined outputs under one unlabeled case.","check_method":{"kind":"report_text_review","reported_in":["AUDIT-EXT","AUDIT-INT"]},"audit_status":"source_boundary_confirmed","current_code_status":"unresolved_source_limit","post_integration_verified":false,"code_references":["/Users/theair/wtc-explainer/site/data/damage_state.json","/Users/theair/wtc-explainer/site/data/damage_zones.json"],"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"Initial full-floor exterior matrices remain distinct from refined aircraft-impact cases.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"Equality of exterior damage between certain initial floor-model inputs does not establish universal equality across all global impact simulations."}},{"id":"INT-001","priority":"P1","title":"Opening and severe-damage footprints have different display meanings","evidence_category":["simulation_result","geometric_inference"],"checked_sources":[{"source_id":"NCSTAR1-2","printed_pages":["187-189","209-211","232-234","254-256"],"figures":["7-12","7-26","7-42","7-56"],"sections":[]},{"source_id":"NCSTAR1-6","printed_pages":["126-128"],"figures":[],"sections":["5.2.2"]},{"source_id":"AUDIT-INT","printed_pages":[],"figures":[],"sections":[]}],"supported_claim":"The maps distinguish openings relevant to ventilation from severe structural damage; both categories were excluded where appropriate in later structural analyses.","limitation":"Rectangular summaries omit isolated member damage and do not establish residual load capacity of amber displayed members. The local NCSTAR1-6 edition is a draft.","recommended_correction":"Keep opening cuts, severe-footprint overlays, and analytical exclusions distinct; label rendered retained amber geometry as a display interpretation.","check_method":{"kind":"report_text_and_legend_review","reported_in":["AUDIT-INT"]},"audit_status":"source_boundary_confirmed","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/data/damage_zones.json","/Users/theair/wtc-explainer/site/js/damage-map.js","/Users/theair/wtc-explainer/site/js/floor-model.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"Original opening footprints remain the baseline. On eight detailed floor/case profiles, separate representative exposed-deck masks remove concrete while keeping corrugated steel deck; severe areas and two-foot exposed-deck shoulders show concrete fragments. All surfaces follow the shared deformation field.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"Masks are coarse source-informed placements, not exact strain contour traces. Fragment dimensions and field interpolation are representative. Detailed source-visible retained truss runs can override summary rectangular omissions."}},{"id":"INT-002","priority":"P1","title":"Recovered trusses do not prove located impact fractures","evidence_category":["physical_evidence","source_limit"],"checked_sources":[{"source_id":"NCSTAR1-3","printed_pages":["36","93-94"],"figures":[],"sections":["5.2.5","6.5"]},{"source_id":"NCSTAR1-2","printed_pages":["275-277","288"],"figures":["7-72"],"sections":[]},{"source_id":"AUDIT-INT","printed_pages":[],"figures":[],"sections":["Evidence boundary"]}],"supported_claim":"The interior auditor found that recovered trusses could not be assigned as-built locations and observed floor damage lacked a quantified interior depth.","limitation":"Collapse and recovery handling prevent assigning particular recovered damage confidently to aircraft impact.","recommended_correction":"Do not call footprint-intersected model trusses confirmed historical failures; preserve historical identity as unresolved unless independently sourced.","check_method":{"kind":"primary_report_review_reported_by_interior_auditor","reported_in":["AUDIT-INT"],"consolidation":"NCSTAR1-3 was not independently reread while consolidating this register."},"audit_status":"source_limit_confirmed_in_cited_audit","current_code_status":"unresolved_source_limit","post_integration_verified":false,"code_references":["/Users/theair/wtc-explainer/site/js/floor-model.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"Historical truss identity remains unresolved; a footprint intersection is not a recovered-fracture identification.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"Collapse and recovery handling prevent assigning particular recovered damage confidently to aircraft impact."}},{"id":"INT-003","priority":"P1","title":"C32T1 reference identity is not an arbitrary selected-floor pair","evidence_category":["reference_geometry","model_input"],"checked_sources":[{"source_id":"NCSTAR1-6C","printed_pages":["69-70"],"figures":["5-25"],"sections":["5.4.1"]},{"source_id":"NCSTAR1-2A","printed_pages":["49"],"figures":[],"sections":["3.3.1"]},{"source_id":"AUDIT-INT","printed_pages":[],"figures":[],"sections":["C32T1 reference detail"]},{"source_id":"AUDIT-APP","printed_pages":[],"figures":[],"sections":["Truss detail damage"]}],"supported_claim":"The NIST reference analysis identifies one truss at WTC1 floor 96, column 143 and a 713-inch analytical span.","limitation":"The app's centered synthetic pair uses different coordinates/span assumptions and lacks a verified historical assignment, especially when WTC2 is selected.","recommended_correction":"Either inspect a located model member at its original coordinates or retain an explicitly unlocated reference sample; never apply tower-local damage merely because a floor is selected.","check_method":{"kind":"source_crosscheck_and_executed_renderer_witness","reported_in":["AUDIT-INT","AUDIT-APP"],"witness":"A generic reference pair disappeared under a selected floor footprint despite no established member assignment."},"audit_status":"discrepancy_present_in_audited_snapshot","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/floor-model.js","/Users/theair/wtc-explainer/site/js/main.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"Located pair details use the same reconstruction as floor/block/tower. Primary and bridging sections remain sourced references. Shared building-side seats, horizontal gussets, stiffeners, bearing angles and tie plates are rendered in member-local coordinates; bolts are one per individual truss.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"The app's centered synthetic pair uses different coordinates/span assumptions and lacks a verified historical assignment, especially when WTC2 is selected."}},{"id":"INT-004","priority":"P1","title":"Source panel regions inform the shared floor inventory","evidence_category":["reference_model_categorization","geometric_inference"],"checked_sources":[{"source_id":"NCSTAR1-2A","printed_pages":["48","192\u2013195"],"figures":["G-2","G-3"]}],"supported_claim":"Types7/8/9 use AppendixG panel-region coordinates. WTC1 short-span beam regions use the supported source orientation, and transverse bridging is clipped at those regions. Replacement beam geometry is centered on its contributing model lines. Existing six WTC2F79 retained beam IDs remain valid.","limitation":"WTC2 cardinal placement and fabrication assignments remain unresolved. Adjacent primary members can belong to different panels: a mixed beam/truss pair is not itself an error. Existing WTC2 individual-line assignments are preserved within the0.5ft source-boundary uncertainty band.","recommended_correction":"Types7/8/9 use AppendixG panel-region coordinates. WTC1 short-span beam regions use the supported source orientation, and transverse bridging is clipped at those regions. Replacement beam geometry is centered on its contributing model lines. Existing six WTC2F79 retained beam IDs remain valid.","check_method":{"kind":"source_table_review_and_code_comparison","reported_in":["AUDIT-INT"]},"audit_status":"inventory_discrepancy_present_in_audited_snapshot","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/floor-model.js","/Users/theair/wtc-explainer/site/js/scene.js","/Users/theair/wtc-explainer/site/js/tower-floors.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Independent source readback and current production geometry/state checks; exact test scope and source registrations are linked.","result":"Types7/8/9 use AppendixG panel-region coordinates. WTC1 short-span beam regions use the supported source orientation, and transverse bridging is clipped at those regions. Replacement beam geometry is centered on its contributing model lines. Existing six WTC2F79 retained beam IDs remain valid.","artifact_or_test_reference":["analysis/structural-expansion-v6/truss-inventory/production-framing-verification.json","site/data/member_sections.json","site/js/floor-framing-regions.js"],"remaining_limitation":"WTC2 cardinal placement and fabrication assignments remain unresolved. Adjacent primary members can belong to different panels: a mixed beam/truss pair is not itself an error. Existing WTC2 individual-line assignments are preserved within the0.5ft source-boundary uncertainty band."}},{"id":"INT-005","priority":"P1","title":"Preserve WTC2 core orientation landmarks","evidence_category":["source_figure_mapping","geometric_registration"],"checked_sources":[{"source_id":"NCSTAR1-2","printed_pages":["233"],"figures":["7-42"],"sections":[]},{"source_id":"AUDIT-INT","printed_pages":[],"figures":[],"sections":["Numeric geometry and source claims"]}],"supported_claim":"The WTC2 source figure locates 508 northwest, 501 southwest, 1008 northeast, and 1001 southeast.","limitation":"Rotating a WTC1 core without the correct numbering transform can place southeast damage in the wrong quadrant.","recommended_correction":"Retain landmark regression checks for the corrected (x, z) to (z, -x) orientation and compare damaged 901/1001 positions across every view.","check_method":{"kind":"source_landmark_review_and_coordinate_check","reported_in":["AUDIT-INT"]},"audit_status":"orientation_correction_observed_in_audit_not_reverified_now","current_code_status":"verified_against_integrated_code","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/tools/build_truss_layout.py","/Users/theair/wtc-explainer/site/data/truss_layout.json"],"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"WTC2 core rotation preserves column508 NW and1001 SE, with tests.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"Rotating a WTC1 core without the correct numbering transform can place southeast damage in the wrong quadrant."}},{"id":"GEO-001","priority":"P1","title":"Story heights, roof elevations and model datums remain distinct","evidence_category":["drawing_transcription","geometric_registration"],"checked_sources":[{"source_id":"LERA-HEIGHTS","printed_pages":[]}],"supported_claim":"All 220 story heights agree with the original LERA floor_heights.txt transcription. Floor geometry uses cumulative story elevations with floor 1 as its local reference. Roof elevations and the top of the floor-110 schedule band are separate quantities; the model is not based on uniform story spacing.","limitation":"Matching the source transcription verifies the implemented schedule, not every historical slab or finish elevation. Raised secondary plates, depressed machine rooms and other local datums require their own sources. Absolute drawing datums must not be replaced by a single story-count calculation.","recommended_correction":"Matching the source transcription verifies the implemented schedule, not every historical slab or finish elevation. Raised secondary plates, depressed machine rooms and other local datums require their own sources. Absolute drawing datums must not be replaced by a single story-count calculation.","check_method":{"kind":"independent_arithmetic_comparison","reported_in":["AUDIT-INT","AUDIT-APP"],"witness":"At audit time WTC1 F96 was 1170 ft by exclusive sum, 1182 ft in JSON/UI, and 1193.891 ft in the guided tour; these are project-data calculations, not surveys."},"audit_status":"datum_and_mapping_discrepancy_present_in_audited_snapshot","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/data/floor_heights.json","/Users/theair/wtc-explainer/site/js/floor-model.js","/Users/theair/wtc-explainer/site/js/scene.js","/Users/theair/wtc-explainer/site/js/tower-floors.js"],"implementation_followup_snapshot":{"source_id":"AUDIT-INT","section":"Follow-up geometry review during implementation","observation":"The later interior CPU check found shared relative elevations consistent across the default WTC 1 and WTC 2 blocks, including WTC 2 ordinate 78.5 = 953 ft. It also found the contextual fire-band midpoint must use floorElevation(f) + storyHeight(f)/2; a minus sign places it one story too low. This is a context overlay, not a computed fire field.","final_integration_verified":false},"verification":{"verification_date":"2026-09-11","verification_method":"Accuracy-note reconciliation against current production data, existing source/mesh review records and the September 11 release checks. Not a new independent measurement of every source drawing.","result":"All 220 story heights agree with the original LERA floor_heights.txt transcription. Floor geometry uses cumulative story elevations with floor 1 as its local reference. Roof elevations and the top of the floor-110 schedule band are separate quantities; the model is not based on uniform story spacing.","artifact_or_test_reference":["analysis/tower-accuracy-review/verification.json","site/data/floor_heights.json","site/data/dimensions.json","analysis/release-model-review/README.md","analysis/view-integration-verification.json"],"remaining_limitation":"Matching the source transcription verifies the implemented schedule, not every historical slab or finish elevation. Raised secondary plates, depressed machine rooms and other local datums require their own sources. Absolute drawing datums must not be replaced by a single story-count calculation."}},{"id":"GEO-002","priority":"P2","title":"Reference section dimensions differ from analytical work points","evidence_category":["reference_geometry","model_input"],"checked_sources":[{"source_id":"NCSTAR1-2A","printed_pages":["48-51"],"figures":["3-16"],"sections":["3.3.1","3.3.2"]},{"source_id":"AUDIT-INT","printed_pages":[],"figures":[],"sections":["Numeric geometry and source claims"]}],"supported_claim":"The primary reference depth is 29 in chord out-to-out;28.05 in is centroid separation and about 30 in is a composite analytical depth. Bridging reference depth is 24 in.","limitation":"Uniform 7.5 in/5 in pair gaps are modeling choices, and the reference section is reused without a full member schedule.","recommended_correction":"Use physical section depth for reference geometry, distinguish analytical dimensions and modeling gaps in UI, and avoid drawing every bridging truss 29 in deep.","check_method":{"kind":"source_dimension_review_and_renderer_comparison","reported_in":["AUDIT-INT"]},"audit_status":"nominal_dimension_mismatch_present_in_audited_snapshot","current_code_status":"unresolved_source_limit","post_integration_verified":false,"code_references":["/Users/theair/wtc-explainer/site/data/member_sections.json","/Users/theair/wtc-explainer/site/js/floor-model.js","/Users/theair/wtc-explainer/site/js/scene.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"Primary/bridging depths retain29/24in reference dimensions; modeled gaps and reused specimens are explicitly distinguished from individual assignments.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"Uniform 7.5 in/5 in pair gaps are modeling choices, and the reference section is reused without a full member schedule."}},{"id":"INT-006","priority":"P2","title":"Core structure and section schedules remain incomplete","evidence_category":["reference_geometry","source_limit"],"checked_sources":[{"source_id":"NCSTAR1-2B_final_ch1-8","printed_pages":[],"figures":["3-6","3-18"]},{"source_id":"NCSTAR1-2B_final_ch9-11","printed_pages":[],"figures":["9-34"]},{"source_id":"NCSTAR1-5G_final","printed_pages":[]},{"source_id":"LERA-ARCHITECTURAL","printed_pages":[]},{"source_id":"PANYNJ-12673","printed_pages":[]}],"supported_claim":"Core aperture profiles cover WTC 1 floors 92\u2013100 and WTC 2 floors 77\u201385. The renderer retains 12 tabulated core-column deflection profiles, 66 damage-table rows and 658 story-column section assignments. Of those assignments, 216 use representative wide-flange dimensions and 7 are partly dimensioned; explicit box exceptions remain. Architectural opening detail does not establish complete structural framing.","limitation":"Core beams repeat the floor-96 North and partial floor-77 South prototypes. Exact sections, joints, trimming around revised openings, reinforcement and core deck remain unresolved. The core slab retains a 4.5-inch/5-inch thickness conflict.","recommended_correction":"Core beams repeat the floor-96 North and partial floor-77 South prototypes. Exact sections, joints, trimming around revised openings, reinforcement and core deck remain unresolved. The core slab retains a 4.5-inch/5-inch thickness conflict.","check_method":{"kind":"report_text_review_and_geometry_inventory","reported_in":["AUDIT-INT"]},"audit_status":"source_and_inventory_limit_confirmed","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/floor-model.js","/Users/theair/wtc-explainer/site/js/scene.js"],"verification":{"verification_date":"2026-09-11","verification_method":"Accuracy-note reconciliation against current production data, existing source/mesh review records and the September 11 release checks. Not a new independent measurement of every source drawing.","result":"Core aperture profiles cover WTC 1 floors 92\u2013100 and WTC 2 floors 77\u201385. The renderer retains 12 tabulated core-column deflection profiles, 66 damage-table rows and 658 story-column section assignments. Of those assignments, 216 use representative wide-flange dimensions and 7 are partly dimensioned; explicit box exceptions remain. Architectural opening detail does not establish complete structural framing.","artifact_or_test_reference":["site/data/core_floor_plan.json","site/data/core_column_schedule.json","site/data/core_section_catalog.json","analysis/core-comprehensive-review/README.md","analysis/release-model-review/README.md","analysis/view-integration-verification.json"],"remaining_limitation":"Core beams repeat the floor-96 North and partial floor-77 South prototypes. Exact sections, joints, trimming around revised openings, reinforcement and core deck remain unresolved. The core slab retains a 4.5-inch/5-inch thickness conflict."}},{"id":"INT-007","priority":"P2","title":"Interval clipping is geometric inference; it does not create supports","evidence_category":["geometric_inference","reference_geometry"],"checked_sources":[{"source_id":"NCSTAR1-6C","printed_pages":["3-4","39-41"],"figures":[],"sections":["2.1","5.2.1"]},{"source_id":"AUDIT-INT","printed_pages":[],"figures":[],"sections":["Verified interval behavior and interpretation"]}],"supported_claim":"Executed interval checks preserve original chord/web slope and portions outside openings, with seats considered only at original endpoints.","limitation":"Tests do not prove original web pitch, all seat failures, individual pair-member damage, or a surviving load path.","recommended_correction":"Retain original member coordinates and endpoint supports, record clipping as inferred intervals, and disclose representative web/seat schedules.","check_method":{"kind":"executed_geometry_regressions","reported_in":["AUDIT-INT"],"cases":["middle opening","overlap precedence","reversed span","diagonal rod","vertical projection","tangent contact","footprint-edge coincidence"]},"audit_status":"geometric_checks_passed_historical_assignment_unresolved","current_code_status":"verified_against_integrated_code","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/damage-map.js","/Users/theair/wtc-explainer/site/js/floor-model.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"Original-coordinate clipping precedes smooth deformation. Chords are subdivided and webs follow the same field. Ten explicitly traced representative retained runs replace matched original pairs, recovering visible steel inside summary openings. Building-side seats remain at original supports; no seats are created at cuts.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"Tests do not prove original web pitch, all seat failures, individual pair-member damage, or a surviving load path."}},{"id":"EXT-006","priority":"P2","title":"Nominal depth must not disappear from bent source stems","evidence_category":["observed_schematic","geometric_inference"],"checked_sources":[{"source_id":"NCSTAR1-1","printed_pages":["10-11"],"figures":[],"sections":[]},{"source_id":"FEMA403-CH2","printed_pages":["2-18"],"figures":["2-16"],"sections":[]},{"source_id":"AUDIT-EXT","printed_pages":[],"figures":[],"sections":["P2: Fixed depth strips"]},{"source_id":"NCSTAR1-1","printed_pages":["11"],"figures":[],"sections":[]},{"source_id":"NCSTAR1-2A","printed_pages":["38"],"figures":[],"sections":[]}],"supported_claim":"FEMA supplies retained elevation contours; NIST describes nominal 14-inch box columns with the spandrel replacing the inner web. Those sources do not provide a complete deformed section survey.","limitation":"Nominal 14-inch depth and 3/8-inch display plates are representative. Source-edge band classification and concealed column continuation are inferred. Plate-specific tearing, exact wall thicknesses and complete depth displacement remain unresolved.","recommended_correction":"Follow retained contours with hollow box walls; recess spandrels to the inside face; preserve a thin source-profile reference and separate measured observations from display assumptions.","check_method":{"kind":"source_profile_horizontal_section_and_code_analysis","reported_in":["AUDIT-EXT"],"quantitative_result":{"profile_width_ft":2.9235,"width_with_column_depth_ft":0.5367,"width_thin_only_ft":2.3867}},"audit_status":"depth_artifact_present_in_audited_snapshot","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/exterior-panels.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Independent source/construction review and CPU source-projection, bent-stem, hollow-end, spandrel-depth and cross-view checks.","result":"Default geometry now uses neutral steel, contour-following hollow column walls, open ends and recessed inner-face spandrels. Bent stems retain depth away from their original centerlines. A separate thin-profile reference preserves FEMA projection. Original 134 retained regions and apertures remain authoritative.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json","analysis/bent_column_depth_method.md","analysis/EXTERIOR_DEFORMATION_METHOD.md","site/js/panel-sections.js"],"remaining_limitation":"Nominal 14-inch depth and 3/8-inch display plates are representative. Source-edge band classification and concealed column continuation are inferred. Plate-specific tearing, exact wall thicknesses and complete depth displacement remain unresolved."}},{"id":"EXT-007","priority":"P1","title":"Spandrel datum and nominal thickness must be consistent","evidence_category":["reference_geometry","model_input","geometric_registration"],"checked_sources":[{"source_id":"NCSTAR1-1","printed_pages":["25"],"figures":["2-9"],"sections":[]},{"source_id":"NCSTAR1-6C","printed_pages":["160"],"figures":["Table 6-1a note"],"sections":[]},{"source_id":"AUDIT-EXT","printed_pages":[],"figures":[],"sections":["Vertical coordinates","Nominal section"]}],"supported_claim":"Fig 2-9 places the spandrel top 13.5 in above floor; a 52 in spandrel therefore has its center 12.5 in below floor. The NIST subsystem uses 52 in by 3/8 in plates.","limitation":"Tower offset and exaggerated thickness differ from floor/detail views. Fractional-floor warping can stretch a schematic plate near non-12-foot stories.","recommended_correction":"Use the common physical datum and an explicit nominal thickness policy; retain source-contour registration separately from claims of exact member dimensions.","check_method":{"kind":"dimensioned_figure_visual_review_and_code_comparison","reported_in":["AUDIT-EXT"]},"audit_status":"dimension_discrepancy_present_in_audited_snapshot","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/exterior-panels.js","/Users/theair/wtc-explainer/site/js/floor-model.js","/Users/theair/wtc-explainer/site/js/scene.js","/Users/theair/wtc-explainer/site/data/member_sections.json"],"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"As-built spandrel centers use12.5in below their named floor, with52in depth. Canonical impact-block spandrels use3/8in nominal thickness. Source contours remain schematic; connection/context proxies are not exact sections.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"Tower offset and exaggerated thickness differ from floor/detail views. Fractional-floor warping can stretch a schematic plate near non-12-foot stories."}},{"id":"EXT-008","priority":"P2","title":"Panel grouping does not prove a universal splice schedule","evidence_category":["observed_schematic","reference_geometry"],"checked_sources":[{"source_id":"FEMA403-CH2","printed_pages":["2-18","2-30"],"figures":["2-16","2-27"],"sections":[]},{"source_id":"NCSTAR1-6C","printed_pages":["6","157-158"],"figures":[],"sections":[]},{"source_id":"NCSTAR1-1","printed_pages":["26"],"figures":["2-10"],"sections":[]},{"source_id":"AUDIT-EXT","printed_pages":[],"figures":[],"sections":["P2: Untraced as-built splice geometry"]}],"supported_claim":"The ordinary-panel stagger in the damage diagrams reverses about the central panel; NIST describes two-story corner modules and special mechanical-floor treatment.","limitation":"A single marching modulo-three schedule at whole floors is not the verified erection schedule. The trace's near 0.4 fractional splice ordinate is not a survey datum.","recommended_correction":"Use source-covered panel schedules where available, distinguish representative joints elsewhere, and avoid claiming synthetic panel IDs are historical fabrication marks.","check_method":{"kind":"figure_schedule_review_and_code_comparison","reported_in":["AUDIT-EXT"]},"audit_status":"schedule_discrepancy_present_in_audited_snapshot","current_code_status":"unresolved_source_limit","post_integration_verified":false,"code_references":["/Users/theair/wtc-explainer/site/js/floor-model.js","/Users/theair/wtc-explainer/site/js/scene.js","/Users/theair/wtc-explainer/site/data/member_sections.json"],"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"FEMA source stagger retained inside coverage. Unverified corner splice markers removed; remaining generic joint patterns explicitly representative.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"A single marching modulo-three schedule at whole floors is not the verified erection schedule. The trace's near 0.4 fractional splice ordinate is not a survey datum."}},{"id":"APP-001","priority":"P1","title":"All located views must consume the same selected case","evidence_category":["application_behavior","simulation_result"],"checked_sources":[{"source_id":"NCSTAR1-2","printed_pages":["183","205","228","251"],"figures":["Tables 7-1, 7-4, 7-6, 7-9"],"sections":[]},{"source_id":"AUDIT-APP","printed_pages":[],"figures":[],"sections":["Main Tower sequence"]},{"source_id":"AUDIT-INT","printed_pages":[],"figures":[],"sections":["Cross-view state audit","Follow-up geometry review during implementation"]}],"supported_claim":"At the audit snapshot Assembly/Plan/Block used the selected case; Tower used base footprints and left core/slab damage unchanged.","limitation":"A shared control value alone does not guarantee shared geometry, inventory or effective historical state.","recommended_correction":"Pass the same case-specific member/core/slab plan to all located renderers and validate records after normalizing view transforms.","check_method":{"kind":"code_inspection_and_executed_matrix_witness","reported_in":["AUDIT-APP","AUDIT-INT"],"witness":"Tower core/slab instance matrices were unchanged after applyDamage in the audited snapshot."},"audit_status":"cross_view_discrepancy_present_in_audited_snapshot","current_code_status":"verified_against_integrated_code","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/scene.js","/Users/theair/wtc-explainer/site/js/floor-model.js"],"implementation_followup_snapshot":{"source_id":"AUDIT-INT","section":"Follow-up geometry review during implementation","observation":"The later interior CPU check found shared FloorBlock embedded in guided towers and FloorBlock/FloorAssembly used by the standalone route. This supersedes the initial disconnected-renderer observation for that checked snapshot, but does not certify all final case/state transitions.","final_integration_verified":true},"verification":{"verification_date":"2026-09-07","verification_method":"Independent source/code audit, actual shared-geometry/controller regressions, and separate live-browser interaction/visual checks.","result":"Actual production scene-controller transitions and shared explorer geometry are checked with the interior datasets loaded. Both towers, all cases, all five main floor views, nine sequence chapters, initiation transforms and all four standalone views retain matching member and surface geometry. Both stack routes now include the complete impact range whenever an impact floor is selected.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json","tools/check_view_integration.mjs","tools/check_support_integration.mjs","tools/check_bow_picking.mjs","analysis/all-view-damage-integration.md"],"remaining_limitation":"A shared control value alone does not guarantee shared geometry, inventory or effective historical state."}},{"id":"APP-002","priority":"P1","title":"Inspection state stays explicit during the tower sequence","evidence_category":["application_behavior"],"checked_sources":[{"source_id":"AUDIT-APP","printed_pages":[],"figures":[],"sections":["Returning from floor mode"]}],"supported_claim":"The audited transition reset lastStage to -1 while relying on previous-stage thresholds to clear damage.","limitation":"A selected post-impact analysis case is not permission to show damaged geometry in a historical pre-impact scene.","recommended_correction":"Derive effective geometry state from current chapter and selected analysis mode on each transition; regression-test post-impact tour to floor view to pre-impact chapter.","check_method":{"kind":"state_transition_code_analysis","reported_in":["AUDIT-APP"]},"audit_status":"transition_defect_present_in_audited_snapshot","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/scene.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"Selected inspection case remains authoritative across chapters. A persistent status explicitly separates inspection state from historical chapter timestamps. Chapters do not silently overwrite the selection.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"The selected inspection case is independent of historical chapter timestamps; it is not a timed physical simulation."}},{"id":"APP-003","priority":"P1","title":"Detail views require selected identity or an explicit reference-only state","evidence_category":["application_behavior","reference_geometry","observed_schematic"],"checked_sources":[{"source_id":"AUDIT-APP","printed_pages":[],"figures":[],"sections":["Panel detail","Truss detail"]},{"source_id":"AUDIT-EXT","printed_pages":[],"figures":[],"sections":["P1: Perimeter-panel detail"]},{"source_id":"NCSTAR1-6C","printed_pages":["69-70"],"figures":["5-25"],"sections":[]},{"source_id":"AUDIT-INT","printed_pages":[],"figures":[],"sections":["Follow-up geometry review during implementation"]}],"supported_claim":"The generic perimeter detail ignored damage while the unlocated generic truss sample could inherit a footprint; picking did not select a detail member.","limitation":"Neither behavior establishes inspection of the real source panel or a located truss.","recommended_correction":"Carry selected member/panel ID across views and reuse its actual record; otherwise keep a clearly unlocated reference sample with global state visibly distinguished.","check_method":{"kind":"executed_renderer_comparison_and_picking_path_review","reported_in":["AUDIT-APP","AUDIT-EXT","AUDIT-INT"]},"audit_status":"detail_identity_discrepancy_present_in_audited_snapshot","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/floor-model.js","/Users/theair/wtc-explainer/site/js/main.js","/Users/theair/wtc-explainer/site/js/scene.js"],"implementation_followup_snapshot":{"source_id":"AUDIT-INT","section":"Follow-up geometry review during implementation","observation":"The later interior CPU check found located pair detail using actual selected model coordinates and removing synthetic slab/deck/core context. The example WTC 2 floor 80 pair remains a model identity with representative section/web geometry, not a confirmed historical fabrication mark.","final_integration_verified":false},"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"Post-impact panel detail selects a FEMA identity; truss detail selects a located model pair. As-built generic panel is explicitly a construction specimen.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"FEMA panel IDs and located model pairs are traceable. Historical fabrication identities and precise interior section assignments remain incomplete."}},{"id":"APP-004","priority":"P1","title":"Standalone tower-floor route needs the same damage service","evidence_category":["application_behavior"],"checked_sources":[{"source_id":"AUDIT-APP","printed_pages":[],"figures":[],"sections":["Alternate route"]},{"source_id":"AUDIT-INT","printed_pages":[],"figures":[],"sections":["Cross-view state audit","Follow-up geometry review during implementation"]}],"supported_claim":"At audit time tower-floors.html loaded no damage state, zones or exterior traces and used a separate as-built renderer.","limitation":"Comments claiming identical or exact logic do not make independent renderers consistent.","recommended_correction":"Delegate to shared damage-aware inventory/rendering or consume the same state service, with matching controls, provenance and inspection/export.","check_method":{"kind":"route_inventory_and_boot_dependency_inspection","reported_in":["AUDIT-APP","AUDIT-INT"]},"audit_status":"alternate_route_disconnected_in_audited_snapshot","current_code_status":"verified_against_integrated_code","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/tower-floors.html","/Users/theair/wtc-explainer/site/js/tower-floors.js"],"implementation_followup_snapshot":{"source_id":"AUDIT-INT","section":"Follow-up geometry review during implementation","observation":"The later interior CPU check found the standalone route consuming shared FloorBlock/FloorAssembly. Final route, control, case, and export behavior still requires application verification.","final_integration_verified":false},"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"Standalone route now consumes the same data and canonical FloorAssembly/FloorBlock renderer through explorer-model.js.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"Comments claiming identical or exact logic do not make independent renderers consistent."}},{"id":"APP-005","priority":"P2","title":"Initiation clones must follow case-driven geometry replacement","evidence_category":["application_behavior"],"checked_sources":[{"source_id":"AUDIT-APP","printed_pages":[],"figures":[],"sections":["Initiation clones"]},{"source_id":"AUDIT-INT","printed_pages":[],"figures":[],"sections":["Follow-up geometry review during implementation"]}],"supported_claim":"InitiationView built its cloned graph and reference links once in the audited snapshot.","limitation":"Updating an existing instance matrix is not equivalent to replacing source groups or geometries; clones can retain an old case.","recommended_correction":"Rebuild or explicitly relink initiation views after shared renderer changes, and test selected-case replacement rather than only visibility changes.","check_method":{"kind":"clone_lifecycle_code_review","reported_in":["AUDIT-APP","AUDIT-INT"]},"audit_status":"integration_hazard_identified_not_reverified","current_code_status":"verified_against_integrated_code","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/scene.js"],"implementation_followup_snapshot":{"source_id":"AUDIT-INT","section":"Follow-up geometry review during implementation","observation":"The later interior CPU check found initiation topology rebuilding with visible lower and upper cloned roots. Bow variants still require separate program-cache keys for different elevation offsets, a stable uniform across rebuilds, and a rendered shader check.","final_integration_verified":true},"verification":{"verification_date":"2026-09-07","verification_method":"Independent source/code audit, actual shared-geometry/controller regressions, and separate live-browser interaction/visual checks.","result":"Initiation copies rebuild with case changes and preserve component visibility, materials, exact split-floor pivots and source-coordinate bowing. Member picking follows the rendered bow and tilt and rejects clipped-away halves.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json","tools/check_view_integration.mjs","tools/check_support_integration.mjs","tools/check_bow_picking.mjs","analysis/all-view-damage-integration.md"],"remaining_limitation":"Updating an existing instance matrix is not equivalent to replacing source groups or geometries; clones can retain an old case."}},{"id":"APP-006","priority":"P1","title":"Layers and slab transforms must preserve structural scope and openings","evidence_category":["application_behavior","geometric_inference"],"checked_sources":[{"source_id":"AUDIT-APP","printed_pages":[],"figures":[],"sections":["Layer controls"]},{"source_id":"AUDIT-EXT","printed_pages":[],"figures":[],"sections":["P2: Facade toggle"]},{"source_id":"AUDIT-INT","printed_pages":[],"figures":[],"sections":["Follow-up geometry review during implementation"]}],"supported_claim":"The audited perimeter toggle hid core columns in Assembly but not Block; X-ray omitted replacement panels; Facade overlaid an uncut box.","limitation":"Cladding damage cannot be inferred wholly from structural damage, and an intact reference envelope must not read as reconstructed surviving facade.","recommended_correction":"Use consistent layer groups and source-to-world coordinates; keep the slab top at floor elevation. Subtract opening rectangles from severe patches, reapply control state after rebuilds, and keep apertures open or explicitly label a reference envelope.","check_method":{"kind":"layer_path_and_geometry_review","reported_in":["AUDIT-APP","AUDIT-EXT","AUDIT-INT"],"followup_failure_witnesses":[{"selection":"WTC 1 floor 95 Case A","point_ft":[0,-70],"reported_failure":"Deck intersects the mapped north opening; its unmapped mirror at [0,70] has no deck. Shape (x,z) rotated about X by -pi/2 reverses world z."},{"selection":"WTC 2 floor 80 Case C","point_ft":[16,95],"reported_failure":"Point lies inside both removed and severe rectangles but intersects an amber slab box; opening precedence is violated."}]},"audit_status":"layer_discrepancy_present_in_audited_snapshot","current_code_status":"verified_against_integrated_code","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/floor-model.js","/Users/theair/wtc-explainer/site/js/scene.js","/Users/theair/wtc-explainer/site/js/tower-floors.js"],"implementation_followup_snapshot":{"source_id":"AUDIT-INT","section":"Follow-up geometry review during implementation","observation":"The later interior CPU/ray check found slab/deck source z reflected by Shape-to-world rotation and severe slab boxes refilling overlapping openings. The findings require final correction and regression checks; the audit did not declare them passed.","final_integration_verified":true},"verification":{"verification_date":"2026-09-07","verification_method":"Independent source/code audit, actual shared-geometry/controller regressions, and separate live-browser interaction/visual checks.","result":"Heavy core and perimeter batches belong to their own layers in every view. Ordinary spandrels and FEMA profiles share the inner column face. X-ray restores each material\u2019s original opacity and depth settings after toggles and case changes; facade envelopes cannot cover impact openings.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json","tools/check_view_integration.mjs","tools/check_support_integration.mjs","tools/check_bow_picking.mjs","analysis/all-view-damage-integration.md"],"remaining_limitation":"Cladding damage cannot be inferred wholly from structural damage, and an intact reference envelope must not read as reconstructed surviving facade."}},{"id":"APP-007","priority":"P2","title":"Visible evidence and exported records must match the rendered case and scope","evidence_category":["application_behavior","simulation_result"],"checked_sources":[{"source_id":"NCSTAR1-2","printed_pages":["187-189","209-211","232-234","254-256"],"figures":["7-12","7-26","7-42","7-56"],"sections":[]},{"source_id":"AUDIT-APP","printed_pages":[],"figures":[],"sections":["Evidence, legend, inspection and export"]}],"supported_claim":"The audited severe-mode carousel still appended a base map; picked records and exports differed in case detail and displayed scope.","limitation":"Counts and exports can identify intersected modeled spans, not whole historical trusses proven destroyed.","recommended_correction":"Use the same member record for rendering, picking and export; include current case, figure, view/floor scope, intervals, identity status and completeness; label comparison figures.","check_method":{"kind":"UI_evidence_and_export_path_review","reported_in":["AUDIT-APP","AUDIT-INT"]},"audit_status":"provenance_discrepancy_present_in_audited_snapshot","current_code_status":"verified_against_integrated_code","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/main.js","/Users/theair/wtc-explainer/site/js/scene.js","/Users/theair/wtc-explainer/site/js/floor-model.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Independent source/code audit, actual shared-geometry/controller regressions, and separate live-browser interaction/visual checks.","result":"Main and standalone source links follow tower and selected case. Inspector records clear when the selection changes. Standard framing records carry tower/case. Exported ledgers contain the visible floor or pair scope; selected-case source policies remain separately available.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json","tools/check_view_integration.mjs","tools/check_support_integration.mjs","tools/check_bow_picking.mjs","analysis/all-view-damage-integration.md"],"remaining_limitation":"Counts and exports can identify intersected modeled spans, not whole historical trusses proven destroyed."}},{"id":"APP-008","priority":"P1","title":"Missing datasets must not produce a silently incomplete damage view","evidence_category":["application_behavior"],"checked_sources":[{"source_id":"AUDIT-APP","printed_pages":[],"figures":[],"sections":["Partial source-load failures"]}],"supported_claim":"The audited boot path did not require exterior traces for post-impact availability; direct impact navigation could select a disabled mode.","limitation":"Interior-only geometry under a caption claiming FEMA exterior reproduction is incomplete evidence presentation.","recommended_correction":"Model dataset availability explicitly, gate state/renderers consistently, and report missing exterior/interior data without suppressing unrelated available evidence.","check_method":{"kind":"dependency_and_failure_path_code_review","reported_in":["AUDIT-APP"]},"audit_status":"failure_path_defect_present_in_audited_snapshot","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/main.js","/Users/theair/wtc-explainer/site/js/exterior-panels.js","/Users/theair/wtc-explainer/site/js/scene.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"Required source datasets load before geometry; missing fetches disable reconstruction and state controls. Network error handling checked by code inspection; no browser fault-injection test performed.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"Interior-only geometry under a caption claiming FEMA exterior reproduction is incomplete evidence presentation."}},{"id":"APP-009","priority":"P2","title":"Route changes and reloads need an explicit selection contract","evidence_category":["application_behavior"],"checked_sources":[{"source_id":"AUDIT-APP","printed_pages":[],"figures":[],"sections":["No cross-route persistence or URL state contract"]}],"supported_claim":"The audited routes stored tower/floor/view/case separately and navigation discarded selections.","limitation":"Persistence of an analysis selection must not override a historical pre-impact chapter's intentional effective as-built state.","recommended_correction":"Use an explicit validated URL/state contract for tower, floor, view, case and selected member, with effective historical state represented separately.","check_method":{"kind":"route_state_and_navigation_review","reported_in":["AUDIT-APP"]},"audit_status":"persistence_gap_present_in_audited_snapshot","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/main.js","/Users/theair/wtc-explainer/site/js/tower-floors.js","/Users/theair/wtc-explainer/site/tower-floors.html"],"verification":{"verification_date":"2026-09-07","verification_method":"Independent source/code audit, actual shared-geometry/controller regressions, and separate live-browser interaction/visual checks.","result":"Validated damage case persists through localStorage and storage events across routes. Both boot paths synchronize storage again after source loading. Tower, floor and view selections remain route-local; the case remains explicit when sequence timestamps change.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json","tools/check_view_integration.mjs","tools/check_support_integration.mjs","tools/check_bow_picking.mjs","analysis/all-view-damage-integration.md"],"remaining_limitation":"Tower, floor and view selections remain local to each route; the damage case is shared."}},{"id":"GEO-003","priority":"P2","title":"Reference dimensions and survey placement do not establish full fabrication geometry","evidence_category":["reference_geometry","source_limit"],"checked_sources":[{"source_id":"NCSTAR1-1","printed_pages":[]},{"source_id":"LERA-ARCHITECTURAL","printed_pages":[]}],"supported_claim":"The model retains the 207 ft 2 in reference-line plan dimension and source-qualified typical modules. Shared survey-derived tower centers now align the towers and sublevels; reviewed lobby column trees and special zones supplement the repeated upper framing.","limitation":"Complete section schedules, centroid offsets, fabrication joints and floor-by-floor construction remain incomplete. Nominal exterior box envelopes and ordinary panel dimensions are references, not universal exact members. Differing source panel-width descriptions remain recorded.","recommended_correction":"Complete section schedules, centroid offsets, fabrication joints and floor-by-floor construction remain incomplete. Nominal exterior box envelopes and ordinary panel dimensions are references, not universal exact members. Differing source panel-width descriptions remain recorded.","check_method":{"kind":"dimensioned_source_crosscheck_and_model_inventory_review","reported_in":["AUDIT-EXT","AUDIT-INT"]},"audit_status":"source_and_geometry_scope_limit_confirmed","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/data/dimensions.json","/Users/theair/wtc-explainer/site/data/member_sections.json","/Users/theair/wtc-explainer/site/js/scene.js","/Users/theair/wtc-explainer/site/js/tower-floors.js"],"verification":{"verification_date":"2026-09-11","verification_method":"Accuracy-note reconciliation against current production data, existing source/mesh review records and the September 11 release checks. Not a new independent measurement of every source drawing.","result":"The model retains the 207 ft 2 in reference-line plan dimension and source-qualified typical modules. Shared survey-derived tower centers now align the towers and sublevels; reviewed lobby column trees and special zones supplement the repeated upper framing.","artifact_or_test_reference":["site/data/dimensions.json","site/js/site-coordinates.js","site/data/lobby_structure.json","analysis/release-model-review/README.md","analysis/view-integration-verification.json"],"remaining_limitation":"Complete section schedules, centroid offsets, fabrication joints and floor-by-floor construction remain incomplete. Nominal exterior box envelopes and ordinary panel dimensions are references, not universal exact members. Differing source panel-width descriptions remain recorded."}},{"id":"GEO-004","priority":"P2","title":"Truss-pair lattice, bridging stations, and span endpoints need separate provenance","evidence_category":["reference_geometry","geometric_registration","geometric_inference"],"checked_sources":[{"source_id":"NCSTAR1-6C","printed_pages":["3-4"],"figures":[],"sections":["2.1"]},{"source_id":"NCSTAR1-2A","printed_pages":["48-51"],"figures":["3-16"],"sections":["3.3.1","3.3.2"]},{"source_id":"FEMA403-CH2","printed_pages":["2-3"],"figures":[],"sections":[]},{"source_id":"AUDIT-INT","printed_pages":[],"figures":[],"sections":["Numeric geometry and source claims"]}],"supported_claim":"Sources describe typical 6 ft 8 in. pair-center spacing and 13 ft 4 in. bridging pitch. NCSTAR 1-2A gives analytical long spans of 59 ft 8 in. and 58 ft 10 in. for different span conditions.","limitation":"Pair centers must be registered to the exterior-column lattice, not recentered arbitrarily. Bridging edge offsets are inferred; the representative model span of 60 ft 1 in. does not reproduce both analytical lengths or a complete as-built endpoint schedule.","recommended_correction":"Retain the documented pair-center origin of -96 2/3 ft and its registration checks. Keep bridging offsets and representative endpoints explicitly inferred; do not silently resnap digitized damage boundaries to a new lattice.","check_method":{"kind":"source_dimension_and_model_coordinate_comparison","reported_in":["AUDIT-INT"],"consolidation":"Synthesis of the interior audit; no new endpoint or fabrication schedule was established."},"audit_status":"reference_dimensions_checked_registration_and_schedule_limited","current_code_status":"unresolved_source_limit","post_integration_verified":false,"code_references":["/Users/theair/wtc-explainer/tools/build_truss_layout.py","/Users/theair/wtc-explainer/site/js/floor-model.js","/Users/theair/wtc-explainer/site/js/scene.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Source audits plus integrated code review and CPU geometry/state regressions; no browser interaction certification.","result":"Exact alternate-column lattice is retained. Existing footprint rounding, span endpoints and bridging station assumptions remain recorded; no new historical measurements invented.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_damage_surfaces.mjs","analysis/verification-results.json"],"remaining_limitation":"Pair centers must be registered to the exterior-column lattice, not recentered arbitrarily. Bridging edge offsets are inferred; the representative model span of 60 ft 1 in. does not reproduce both analytical lengths or a complete as-built endpoint schedule."}},{"id":"EXT-009","priority":"P1","title":"M-2 inward bend: observed direction and illustrative amount","evidence_category":["photographic_observation","geometric_inference"],"checked_sources":[{"source_id":"NCSTAR1-3Cv1","printed_pages":["41","98","99","103","124"],"figures":["2-17","3-5"],"sections":[]}],"supported_claim":"NIST correlates M-2, columns 129\u2013131 at floors 96\u201399, with pre-collapse photographs. Lower portions bent inward with the floor-97 slab acting as a fulcrum. No bend displacement or angle is supplied.","limitation":"The exact hinge axis, angle, displaced surface and torn-plate geometry are unmeasured. Figure 3-5 has a conflicting 94\u201397 caption; text on p103 and Figure 2-17 identify the 96\u201399 panel.","recommended_correction":"Only FEMA panel WTC1-N-C129-131-F96.4-99.4 receives an inward depth warp below floor 97. The explicitly illustrative 1:1 slope is 45 degrees and yields at most 4.57536 ft inward at the retained lower ordinate 96.61872. This is not a NIST measurement or a conserved-length reconstruction. Source x/y and the thin reference remain unchanged. Every view and export uses the same rule.","check_method":{"kind":"source_photograph_and_recovered_piece_correspondence","reported_in":["analysis/EXTERIOR_DEFORMATION_METHOD.md"]},"audit_status":"source_constraints_recorded","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/exterior-panels.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Independent primary-source review; numerical checks establish only the declared representation.","result":"Only FEMA panel WTC1-N-C129-131-F96.4-99.4 receives an inward depth warp below floor 97. The explicitly illustrative 1:1 slope is 45 degrees and yields at most 4.57536 ft inward at the retained lower ordinate 96.61872. This is not a NIST measurement or a conserved-length reconstruction. Source x/y and the thin reference remain unchanged. Every view and export uses the same rule.","artifact_or_test_reference":["analysis/exterior_out_of_plane_features.json","analysis/EXTERIOR_DEFORMATION_METHOD.md","tools/check_model.mjs"],"remaining_limitation":"The exact hinge axis, angle, displaced surface and torn-plate geometry are unmeasured. Figure 3-5 has a conflicting 94\u201397 caption; text on p103 and Figure 2-17 identify the 96\u201399 panel."}},{"id":"EXT-010","priority":"P1","title":"M-30 retained fragments supplement the FEMA trace","evidence_category":["photographic_observation","geometric_inference"],"checked_sources":[{"source_id":"NCSTAR1-3Cv1","printed_pages":["39","40","98","99","101","102","121"],"figures":["2-14","2-16","3-2"],"sections":[]}],"supported_claim":"NIST identifies retained lower fragments of M-30 columns 132 and 133, with local outer-web and spandrel folds near floor 95. The nearly 90-degree fold is a local plate observation.","limitation":"Lower splice registration, torn outline, lip lengths and exact fold angle remain representative within recorded ranges. Column 134 and a complete three-story panel are not restored.","recommended_correction":"Two lower hollow stems, a retained spandrel remnant and local inward-folded lips supplement the unchanged FEMA source polygons. The retained columns use the independently identified type 123 plate schedule.","check_method":{"kind":"source_photograph_and_recovered_piece_correspondence","reported_in":["analysis/EXTERIOR_DEFORMATION_METHOD.md"]},"audit_status":"source_constraints_recorded","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["/Users/theair/wtc-explainer/site/js/exterior-fragments.js","/Users/theair/wtc-explainer/site/data/exterior_fragments.json"],"verification":{"verification_date":"2026-09-07","verification_method":"Primary-source review and registered source overlays where applicable; production geometry/state tests; targeted live browser inspection. Final integration: 253 checks passed, with no failures.","result":"Two lower hollow stems, a retained spandrel remnant and local inward-folded lips supplement the unchanged FEMA source polygons. The retained columns use the independently identified type 123 plate schedule.","artifact_or_test_reference":["tools/check_exterior_supplements.mjs","site/data/exterior_fragments.json","analysis/exterior-gap-review/REVIEW.md","analysis/view-integration-verification.json","analysis/evidence-expansion-browser-checks.json"],"remaining_limitation":"Lower splice registration, torn outline, lip lengths and exact fold angle remain representative within recorded ranges. Column 134 and a complete three-story panel are not restored."}},{"id":"INT-008","priority":"P1","title":"Representative bent trusses and retained source runs","evidence_category":["calculated_damage","geometric_inference"],"checked_sources":[{"source_id":"NCSTAR1-2","printed_pages":["184","185","186","187","207","208","209","229","230","231","252","253","254"],"figures":[],"sections":[]}],"supported_claim":"NIST NCSTAR1-2 supplies plan and front views of calculated truss damage for WTC1 floors95\u201396 and WTC2 floors80\u201381 in both cases.","limitation":"Controls, vertical drops and pair assignment are representative fits to published views, not recovered solver nodes.","recommended_correction":"Eight profiles contain26 localized deformation controls and10 retained polylines. The same paths drive floor, block, tower and selected-pair geometry. Retained polylines replace their matched original pairs and are not warped twice.","check_method":{"kind":"source_view_comparison_and_geometry_regression"},"audit_status":"representative_reconstruction","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["site/js/interior-reconstruction.js","site/js/interior-remnants.js","site/js/interior-surfaces.js","site/js/floor-model.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Independent source audit and actual geometry comparisons across views.","result":"Fourteen profiles contain36 localized controls,10 retained truss polylines and3 retained beam paths. The same paths drive floor, block and tower geometry; truss pair inspection uses its matched truss identity. Explicit retained paths are not warped twice.","artifact_or_test_reference":["tools/check_interior_reconstruction.mjs","analysis/interior-reconstruction-verification.log","analysis/interior_connection_audit.md"],"remaining_limitation":"Controls, vertical drops and pair assignment are representative fits to published views, not recovered solver nodes."}},{"id":"INT-009","priority":"P1","title":"Separate damaged concrete from retained steel deck","evidence_category":["calculated_damage","geometric_inference"],"checked_sources":[{"source_id":"NCSTAR1-2","printed_pages":["184","185","186","187","207","208","209","229","230","231","252","253","254"],"figures":[],"sections":[]}],"supported_claim":"NIST distinguishes modeled concrete failure from metal-deck rupture in Figs7-11/25/41/55; red concrete-failure regions need not be through-floor holes.","limitation":"Mask boundaries are generally5ft-scale estimates; fragment geometry and two-foot fractured shoulders are illustrative.","recommended_correction":"32 coarse exposed-deck masks across eight cases/floors reveal corrugated deck. Concrete fragments show local breakup; original openings and core voids remain empty. Surface picking and exports retain the source record.","check_method":{"kind":"source_view_comparison_and_geometry_regression"},"audit_status":"representative_reconstruction","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["site/js/interior-reconstruction.js","site/js/interior-remnants.js","site/js/interior-surfaces.js","site/js/floor-model.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Independent source audit and actual geometry comparisons across views.","result":"32 coarse exposed-deck masks across eight cases/floors reveal corrugated deck. Concrete fragments show local breakup; original openings and core voids remain empty. Surface picking and exports retain the source record.","artifact_or_test_reference":["tools/check_interior_reconstruction.mjs","analysis/interior-reconstruction-verification.log","analysis/interior_connection_audit.md"],"remaining_limitation":"Mask boundaries are generally5ft-scale estimates; fragment geometry and two-foot fractured shoulders are illustrative."}},{"id":"INT-010","priority":"P1","title":"Representative connection assemblies and separation","evidence_category":["calculated_damage","geometric_inference"],"checked_sources":[{"source_id":"NCSTAR1-6C","printed_pages":["39","40","41","42","43","44"],"figures":[],"sections":[]}],"supported_claim":"NIST1-6C pp39\u201344 documents two bolts per ordinary truss pair, shared seats, vertical stiffeners/stand-offs, horizontal exterior gussets and distinct connection-failure paths.","limitation":"Representative separation does not assign a historical weld/bolt/walk-off failure mechanism; detailed seat classes are not assigned outside the documented floor96 quadrant.","recommended_correction":"Seat plates use representative1/2in thickness; core bolt gauges are8.5in short-span/9.5in long-span. Shared seats stay at original anchors, displaced bearing angles follow the reconstructed truss end, bolts are omitted at visibly separated ends, and ties occur at original ends/bridging stations.","check_method":{"kind":"source_view_comparison_and_geometry_regression"},"audit_status":"representative_reconstruction","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"code_references":["site/js/interior-reconstruction.js","site/js/interior-remnants.js","site/js/interior-surfaces.js","site/js/floor-model.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Independent source/code audit, actual shared-geometry/controller regressions, and separate live-browser interaction/visual checks.","result":"Building-side fixtures are omitted where FEMA entry-face steel or the documented WTC1 ejected south panel is absent. Retained truss-side bearing fragments remain. Building fixtures on M-2 follow the same illustrative inward displacement as its steel. Separation is measured relative to retained wall support. The existing representative shared seats, two bolts per pair and bottom ties remain consistent across floor, detail and stack views.","artifact_or_test_reference":["tools/check_interior_reconstruction.mjs","analysis/interior-reconstruction-verification.log","analysis/interior_connection_audit.md","tools/check_view_integration.mjs","tools/check_support_integration.mjs","tools/check_bow_picking.mjs","analysis/all-view-damage-integration.md"],"remaining_limitation":"Representative separation does not assign a historical weld/bolt/walk-off failure mechanism; detailed seat classes are not assigned outside the documented floor96 quadrant."}},{"id":"APP-010","priority":"P1","title":"Reloads must not mix model and data revisions","evidence_category":["application_behavior"],"checked_sources":[{"source_id":"AUDIT-APP","printed_pages":[],"figures":[],"sections":["Live browser integration audit"]}],"supported_claim":"The existing browser had older modules loaded; a refresh exposed an incompatible scene/floor module pair and prevented initialization.","limitation":"Source files on disk and a changed document URL do not establish which module graph the browser executes.","recommended_correction":"Fingerprint every application/vendor module in both import maps, version entry scripts and stylesheets, and request source datasets without cache.","check_method":{"kind":"browser_console_reproduction_and_reload_verification"},"audit_status":"corrected_in_integration_review","current_code_status":"verified_against_integrated_code","post_integration_verified":true,"code_references":["tools/version_modules.py","tools/package_static.py","site/index.html","site/tower-floors.html","site/js/main.js","site/js/tower-floors.js"],"verification":{"verification_date":"2026-09-07","verification_method":"Live-browser reload and route changes; complete static module graph validation.","result":"Both routes use content-fingerprinted module graphs and entry scripts. Source JSON requests bypass old cached versions. Browser reloads initialize successfully and the old module export error is gone.","artifact_or_test_reference":["analysis/all-view-damage-integration.md","tools/version_modules.py","tools/package_static.py"],"remaining_limitation":"An already-open document must reload to apply changed application code."}},{"id":"INT-011","priority":"P1","title":"Twelve core-column centerlines use NIST calculated deflection amplitudes","evidence_category":["primary_source","representative_geometry"],"checked_sources":[{"source_id":"NCSTAR1-2","printed_pages":["182\u2013183","204\u2013205","227\u2013228","249\u2013251"],"figures":["7-6","7-21","7-37","7-51"],"tables":["7-1","7-4","7-6","7-9"]}],"supported_claim":"Tables 7-1, 7-4, 7-6 and 7-9 publish twelve heavy-column lateral deflections across the two towers and two impact cases.","code_references":["/Users/theair/wtc-explainer/site/js/core-reconstruction.js","/Users/theair/wtc-explainer/site/data/core_column_deformation.json","/Users/theair/wtc-explainer/site/data/core_column_table_records.json"],"recommended_correction":"Twelve source-identified retained columns bend continuously in absolute elevation with tabulated maxima of 10\u201332 inches; severed segments remain omitted. All 66 table rows, including moderate and light states, are preserved in case-scoped exports.","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"limitation":"Peak elevations, detailed curves and complete 3D displacement vectors are not established by the tables. Moderate and light columns receive their recorded classifications without invented centerline offsets.","verification":{"verification_date":"2026-09-07","verification_method":"Primary-source review and registered source overlays where applicable; production geometry/state tests; targeted live browser inspection. Final integration: 253 checks passed, with no failures.","result":"Twelve source-identified retained columns bend continuously in absolute elevation with tabulated maxima of 10\u201332 inches; severed segments remain omitted. All 66 table rows, including moderate and light states, are preserved in case-scoped exports.","artifact_or_test_reference":["tools/check_core_reconstruction.mjs","tools/check_view_integration.mjs","analysis/view-integration-verification.json","analysis/evidence-expansion-browser-checks.json"],"remaining_limitation":"Peak elevations, detailed curves and complete 3D displacement vectors are not established by the tables. Moderate and light columns receive their recorded classifications without invented centerline offsets."}},{"id":"INT-012","priority":"P1","title":"Impact core openings follow tower-specific plans within reviewed areas","evidence_category":["primary_source","representative_geometry"],"checked_sources":[{"source_id":"LERA-ARCHITECTURAL","printed_pages":[],"drawings":["A-A-148","A-A-150","A-A-151","A-A-153"]},{"source_id":"PANYNJ-12673","printed_pages":[],"drawings":["A-B-135","A-B-137","A-B-139","A-B-141","A-B-143","A-B-145","A-B-147","A-B-149","A-AB-211"]}],"supported_claim":"WTC 1 floors 92\u2013100 and WTC 2 floors 77\u201385 have differentiated aperture profiles. Reviewed hoistways, stair openings and service areas replace prototype geometry only within their source masks. Tower B uses independent original drawings, including raised floor-80 secondary plates and depressed floor-81 machine-room plates. The North 80-span and South partial 158-span beam prototypes remain separate from this architectural review.","code_references":["/Users/theair/wtc-explainer/site/js/core-floor-reconstruction.js","/Users/theair/wtc-explainer/site/data/core_floor_plan.json"],"recommended_correction":"North elevators 6/7/50 clear faces and adjacent services, smaller South openings, floor-81 machine elevation and floor-82 transfer headroom remain unresolved. Typical plan-reading uncertainty is approximately 0.75\u20131 ft for the reviewed circulation geometry; each source registration retains its own uncertainty. A small control-fit residual is not a construction tolerance. Aperture polygon counts can include clipped fragments and are not counts of historical openings.","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"limitation":"North elevators 6/7/50 clear faces and adjacent services, smaller South openings, floor-81 machine elevation and floor-82 transfer headroom remain unresolved. Typical plan-reading uncertainty is approximately 0.75\u20131 ft for the reviewed circulation geometry; each source registration retains its own uncertainty. A small control-fit residual is not a construction tolerance. Aperture polygon counts can include clipped fragments and are not counts of historical openings.","verification":{"verification_date":"2026-09-11","verification_method":"Accuracy-note reconciliation against current production data, existing source/mesh review records and the September 11 release checks. Not a new independent measurement of every source drawing.","result":"WTC 1 floors 92\u2013100 and WTC 2 floors 77\u201385 have differentiated aperture profiles. Reviewed hoistways, stair openings and service areas replace prototype geometry only within their source masks. Tower B uses independent original drawings, including raised floor-80 secondary plates and depressed floor-81 machine-room plates. The North 80-span and South partial 158-span beam prototypes remain separate from this architectural review.","artifact_or_test_reference":["site/data/core_floor_plan.json","analysis/core-impact-93-95-review/README.md","analysis/wtc2-independent-core-review/README.md","analysis/wtc2-express-terminal-review/README.md","analysis/release-model-review/README.md","analysis/view-integration-verification.json"],"remaining_limitation":"North elevators 6/7/50 clear faces and adjacent services, smaller South openings, floor-81 machine elevation and floor-82 transfer headroom remain unresolved. Typical plan-reading uncertainty is approximately 0.75\u20131 ft for the reviewed circulation geometry; each source registration retains its own uncertainty. A small control-fit residual is not a construction tolerance. Aperture polygon counts can include clipped fragments and are not counts of historical openings."}},{"id":"EXT-011","priority":"P1","title":"Recovered-panel column plate schedules","evidence_category":["primary_source","representative_geometry"],"checked_sources":[{"source_id":"NCSTAR1-3B_final","printed_pages":["13\u201314","23","51"],"figures":["3-5(b)"],"tables":["3-5","4-1"]}],"supported_claim":"NIST NCSTAR1-3B Tables 4-1 and 3-5 identify M-2 as type122, M-30 as type123, and M-27 columns129/130/131 as types123/123/124 (inside-view ordering).","code_references":["/Users/theair/wtc-explainer/site/js/exterior-panels.js","/Users/theair/wtc-explainer/site/js/exterior-fragments.js"],"recommended_correction":"M-2 uses 3/8-inch sides and 1/4-inch webs. M-30 uses 7/16-inch sides and 1/4-inch webs. M-27 columns129/130 use 7/16-inch sides, column131 uses 1/2-inch sides, all with 1/4-inch webs. Spandrels are 3/8 inch. The 25 independent M27/M2 geometry checks pass.","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"limitation":"Nominal 14-inch box envelopes, concealed continuations, torn surfaces and exact local deformations remain representative. These schedules are not assigned to unrelated panels.","verification":{"verification_date":"2026-09-07","verification_method":"Independent final report table readback, inside/outside orientation review and rays measuring the actual emitted plate gauges.","result":"M-2 uses 3/8-inch sides and 1/4-inch webs. M-30 uses 7/16-inch sides and 1/4-inch webs. M-27 columns129/130 use 7/16-inch sides, column131 uses 1/2-inch sides, all with 1/4-inch webs. Spandrels are 3/8 inch. The 25 independent M27/M2 geometry checks pass.","artifact_or_test_reference":["tools/check_m27_sections.mjs","analysis/nist-panel-crosscheck/m27-section-verification.json"],"remaining_limitation":"Nominal 14-inch box envelopes, concealed continuations, torn surfaces and exact local deformations remain representative. These schedules are not assigned to unrelated panels."}},{"id":"APP-011","priority":"P1","title":"Bowed geometry and lighting share the deformation field","evidence_category":["code_audit","geometry_verification"],"checked_sources":[],"supported_claim":"The normals used for lighting must remain perpendicular to the displayed deformed surfaces.","code_references":["/Users/theair/wtc-explainer/site/js/bow-picking.js","/Users/theair/wtc-explainer/site/js/scene.js"],"recommended_correction":"Bowing now transforms normals with the inverse-transpose deformation Jacobian, in the same tower coordinates as vertices and CPU picking, including instanced members and tilted clones.","current_code_status":"verified_against_integrated_code","post_integration_verified":true,"limitation":"This corrects geometric lighting. It does not create a structural simulation or add historical deformation evidence.","verification":{"verification_date":"2026-09-07","verification_method":"Primary-source review and registered source overlays where applicable; production geometry/state tests; targeted live browser inspection. Final integration: 253 checks passed, with no failures.","result":"Bowing now transforms normals with the inverse-transpose deformation Jacobian, in the same tower coordinates as vertices and CPU picking, including instanced members and tilted clones.","artifact_or_test_reference":["tools/check_bow_picking.mjs","analysis/evidence-expansion-browser-checks.json","analysis/view-integration-verification.json","analysis/evidence-expansion-browser-checks.json"],"remaining_limitation":"This corrects geometric lighting. It does not create a structural simulation or add historical deformation evidence."}},{"id":"APP-012","priority":"P1","title":"Initiation display clones preserve shared geometry and evidence","evidence_category":["code_audit","geometry_verification"],"checked_sources":[],"supported_claim":"Repeated tower initiation must retain the selected damage state without duplicating the full per-instance evidence graph or disposing shared source geometry.","recommended_correction":"Use lightweight display clones with shared immutable geometry, buffers and evidence, separate owned clipping materials, and released old visibility links.","limitation":"Memory readings use production scene code with a stubbed GPU renderer; they are one-run CPU diagnostics, not a browser GPU performance benchmark.","code_references":["/Users/theair/wtc-explainer/site/js/display-clone.js","/Users/theair/wtc-explainer/site/js/scene.js"],"current_code_status":"verified_against_integrated_code","post_integration_verified":true,"verification":{"verification_date":"2026-09-07","verification_method":"Clone ownership, identity, disposal and case-restoration tests; full 253-check integration; nine live chapter transitions plus twelve bow/onset case combinations.","result":"The recursive evidence-copy allocation was removed. In the scoped diagnostic, immediate post-onset heap fell from 1735.39 MiB to 70.80 MiB. Live browser chapter and case switching completed without further crash or console errors.","artifact_or_test_reference":["tools/check_display_clone.mjs","analysis/initiation-memory-review.md","analysis/view-integration-verification.json","analysis/evidence-expansion-browser-checks.json"],"remaining_limitation":"Shared evidence is treated as immutable. CPU measurements exclude GPU memory and do not establish performance on every device."}},{"id":"EXT-012","priority":"P1","title":"M-27 above-floor 95 inward bend","evidence_category":["source_review","representative_reconstruction","geometry_verification"],"checked_sources":[{"source_id":"NCSTAR1-3Cv1","printed_pages":["40","98","109"],"figures":["2-16"]}],"supported_claim":"NCSTAR1-3C\u2019s pre-collapse photo and text identify inward-bent columns above the floor 95 spandrel of M-27; the lower portion appears intact.","recommended_correction":"The retained FEMA M-27 geometry receives an inward depth fold only above the floor 95 hinge. Shared support queries use the same above/below-hinge rule. Source projection and removed upper material remain unchanged.","limitation":"The source supplies direction, not measured bend angle or hinge coordinates. Display slope 1 is representative; only the existing short retained lip bends. Recovered splaying and broken lower connections are not assigned to impact.","code_references":["site/js/exterior-panels.js","site/js/exterior-folds.js","site/js/exterior-support.js"],"current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"verification":{"verification_date":"2026-09-07","verification_method":"Independent source transcription, renderer inspection, production geometry and browser verification.","result":"The retained FEMA M-27 geometry receives an inward depth fold only above the floor 95 hinge. Shared support queries use the same above/below-hinge rule. Source projection and removed upper material remain unchanged.","artifact_or_test_reference":["tools/check_model.mjs","tools/check_support_integration.mjs"],"remaining_limitation":"The source supplies direction, not measured bend angle or hinge coordinates. Display slope 1 is representative; only the existing short retained lip bends. Recovered splaying and broken lower connections are not assigned to impact."}},{"id":"INT-013","priority":"P1","title":"Six additional floor/case deformation profiles","evidence_category":["source_review","representative_reconstruction","geometry_verification"],"checked_sources":[{"source_id":"NCSTAR1-2B_final_ch9-11","printed_pages":["216\u2013217","243\u2013244","269\u2013270","304\u2013305"],"figures":["9-14","9-15","9-35","9-36","9-54","9-55","9-84","9-85"]}],"supported_claim":"The detailed final NCSTAR1-2B plates include WTC 1F94 and WTC 2F79/F82 in both impact cases.","recommended_correction":"The shared interior profile set now covers 14 floor/case combinations. Ten added plan/front assets are selected by floor and case in both application routes. WTC 2F82 base has no assigned vertical displacement.","limitation":"Topology and direction follow calculated raster figures; control amplitudes/radii and vertical interpolation remain representative. No additional slab openings or truss fracture identities are asserted.","code_references":["site/data/interior_deformation.json","site/js/damage-evidence.js"],"current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"verification":{"verification_date":"2026-09-07","verification_method":"Independent source transcription, renderer inspection, production geometry and browser verification.","result":"The shared interior profile set now covers 14 floor/case combinations. Ten added plan/front assets are selected by floor and case in both application routes. WTC 2F82 base has no assigned vertical displacement.","artifact_or_test_reference":["tools/check_interior_reconstruction.mjs","tools/check_additional_interior_floors.mjs","analysis/additional-interior-floors/README.md"],"remaining_limitation":"Topology and direction follow calculated raster figures; control amplitudes/radii and vertical interpolation remain representative. No additional slab openings or truss fracture identities are asserted."}},{"id":"INT-014","priority":"P1","title":"Floor 79 retained framing must remain beam framing","evidence_category":["source_review","representative_reconstruction","geometry_verification"],"checked_sources":[{"source_id":"NCSTAR1-2B_final_ch9-11","printed_pages":["305"],"figures":["9-85"]},{"source_id":"NCSTAR1-2A","printed_pages":["192","194"],"tables":["G-1"],"figures":["G-2"]}],"supported_claim":"Three connected lanes remain visible in WTC 2 severe floor 79 despite the coarse removed rectangle. The registered Type8 plan places these lanes in a beam substitution region.","recommended_correction":"Three explicit retained beam paths replace the six original primary-model IDs representing three beam lanes. They bypass the coarse member mask without restoring slab or adding supports, dampers or a second deformation.","limitation":"The south-side interpretation of FigG2 is registered; that figure has no north arrow. Lane registration residuals are below 0.5 ft. Vertical drops, individual sections, connection behavior and end fixity remain representative.","code_references":["site/js/floor-model.js","site/js/interior-remnants.js"],"current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"verification":{"verification_date":"2026-09-07","verification_method":"Independent source transcription, renderer inspection, production geometry and browser verification.","result":"Three explicit retained beam paths replace the six original primary-model IDs representing three beam lanes. They bypass the coarse member mask without restoring slab or adding supports, dampers or a second deformation.","artifact_or_test_reference":["tools/check_additional_interior_floors.mjs"],"remaining_limitation":"The south-side interpretation of FigG2 is registered; that figure has no north arrow. Lane registration residuals are below 0.5 ft. Vertical drops, individual sections, connection behavior and end fixity remain representative."}},{"id":"GEO-005","priority":"P1","title":"Core-column section schedule and historical dimensions","evidence_category":["source_review","representative_reconstruction","geometry_verification"],"checked_sources":[{"source_id":"NCSTAR1-5G_final","printed_pages":["62","115","284\u2013293"],"tables":["B-4","B-5","B-6","B-7","B-8"]},{"source_id":"AISC-DG15-2002","printed_pages":["28"],"tables":["2.2.1"]},{"source_id":"NCSTAR1-3A_final","printed_pages":["10"],"figures":["2-6"]}],"supported_claim":"NCSTAR1-5G AppendixB tabulates47 core columns across WTC 1F92\u201399 and WTC 2F78\u201383: 658 story-column assignments. Historical AISC tables resolve 25 scheduled WF sizes; NIST sample drawings partly resolve 2 others.","recommended_correction":"Every view uses the same source-selected core section and world-axis orientation, partitioned at story boundaries. The 658 assignments select 144 box profiles, 291 complete historical WF profiles, 7 partly dimensioned WF profiles and 216 representative WF profiles. The 144 boxes include 2 explicit borrowed-dimension exceptions. C801F77 adds a separately identified box family with borrowed adjacent dimensions.","limitation":"NIST thermal-model sections are not a complete fabrication survey. Remaining WF dimensions, rolled fillets, unequal-flange mirror choice, box lips/corner fabrication, workpoint versus centroid and exact within-story splices are unresolved. Supplemental reinforcement dimensions are not substituted for parent-section gauges.","code_references":["site/js/core-sections.js","site/js/core-reconstruction.js","site/data/core_column_schedule.json","site/data/core_section_catalog.json"],"current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"verification":{"verification_date":"2026-09-07","verification_method":"Independent source transcription, renderer inspection, production geometry and browser verification.","result":"Every view uses the same source-selected core section and world-axis orientation, partitioned at story boundaries. The 658 assignments select 144 box profiles, 291 complete historical WF profiles, 7 partly dimensioned WF profiles and 216 representative WF profiles. The 144 boxes include 2 explicit borrowed-dimension exceptions. C801F77 adds a separately identified box family with borrowed adjacent dimensions.","artifact_or_test_reference":["tools/check_core_sections.mjs","tools/check_core_reconstruction.mjs","analysis/core-section-review/REVIEW.md"],"remaining_limitation":"NIST thermal-model sections are not a complete fabrication survey. Remaining WF dimensions, rolled fillets, unequal-flange mirror choice, box lips/corner fabrication, workpoint versus centroid and exact within-story splices are unresolved. Supplemental reinforcement dimensions are not substituted for parent-section gauges."}},{"id":"GEO-006","priority":"P1","title":"Explicit core section transition conflicts","evidence_category":["source_review","representative_reconstruction","geometry_verification"],"checked_sources":[{"source_id":"NCSTAR1-2A","printed_pages":["17"]},{"source_id":"NCSTAR1-5G_final","printed_pages":["290\u2013293"],"tables":["B-7","B-8"]},{"source_id":"NCSTAR1-3B_final","printed_pages":["10"],"tables":["3-3"]}],"supported_claim":"NCSTAR1-2A impact-reference transitions disagree with thermal AppendixB for C1008F81\u201382 and C508F83. Recovered C801 pieces independently establish its box family atF77.","recommended_correction":"C1008F81\u201382 retains the impact-reference box family with its ownF80 box dimensions explicitly extrapolated; thermal14WF730 remains as an alternate. C508F83 retains its explicitly tabulated box with a transition conflict. C801F77 uses its ownF78 dimensions as a disclosed extrapolation.","limitation":"The evidence does not resolve exact splice heights or actual dimensions at the disputed elevations. Generic rolled sections are not substituted for known box families. Added flange reinforcement is documented but not placed without enough dimensions.","code_references":["site/js/core-sections.js"],"current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"verification":{"verification_date":"2026-09-07","verification_method":"Independent source transcription, renderer inspection, production geometry and browser verification.","result":"C1008F81\u201382 retains the impact-reference box family with its ownF80 box dimensions explicitly extrapolated; thermal14WF730 remains as an alternate. C508F83 retains its explicitly tabulated box with a transition conflict. C801F77 uses its ownF78 dimensions as a disclosed extrapolation.","artifact_or_test_reference":["tools/check_core_sections.mjs"],"remaining_limitation":"The evidence does not resolve exact splice heights or actual dimensions at the disputed elevations. Generic rolled sections are not substituted for known box families. Added flange reinforcement is documented but not placed without enough dimensions."}},{"id":"EXT-013","priority":"P1","title":"Apply exact sampled exterior schedules with recovered-panel precedence","evidence_category":["source_review","representative_reconstruction","geometry_verification"],"checked_sources":[{"source_id":"NCSTAR1-5G_final","printed_pages":["Appendix B"],"tables":["B-3"]},{"source_id":"NCSTAR1-3B_final","printed_pages":["14","51"],"tables":["3-5","4-1"]}],"supported_claim":"The1119 resolved entries among1120 sampled thermal-model rows are eligible only for their exact tower/column/story; one type23 conflict and unlisted columns retain explicit fallbacks. Side, outer-web and inner-web gauges are applied separately. M2/M27/M30 nominal recovered gauges take priority in reference and damaged states.","recommended_correction":"The1119 resolved entries among1120 sampled thermal-model rows are eligible only for their exact tower/column/story; one type23 conflict and unlisted columns retain explicit fallbacks. Side, outer-web and inner-web gauges are applied separately. M2/M27/M30 nominal recovered gauges take priority in reference and damaged states.","limitation":"TableB3 t3 is the inner column web, not a spandrel assignment. Thermal dimensions are rounded meters. Actual fabrication splices and universal facade coverage remain unresolved; identified panel bounds follow the diagram registration.","code_references":["site/data/exterior_column_schedule.json"],"current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"verification":{"verification_date":"2026-09-07","verification_method":"Independent source readback and current production geometry/state checks; exact test scope and source registrations are linked.","result":"The1119 resolved entries among1120 sampled thermal-model rows are eligible only for their exact tower/column/story; one type23 conflict and unlisted columns retain explicit fallbacks. Side, outer-web and inner-web gauges are applied separately. M2/M27/M30 nominal recovered gauges take priority in reference and damaged states.","artifact_or_test_reference":["analysis/structural-expansion-v6/exterior/production-exterior-verification.json","site/data/exterior_column_schedule.json","site/js/exterior-known-sections.js"],"remaining_limitation":"TableB3 t3 is the inner column web, not a spandrel assignment. Thermal dimensions are rounded meters. Actual fabrication splices and universal facade coverage remain unresolved; identified panel bounds follow the diagram registration."}},{"id":"EXT-014","priority":"P1","title":"Later NIST observed contours revise the FEMA entry-wall baseline","evidence_category":["observed_schematic","geometric_registration","source_limit"],"checked_sources":[{"source_id":"NCSTAR1-5A_final_ch1-8","printed_pages":["65","111"],"figures":["6-6","7-25"]},{"source_id":"NCSTAR1-2","printed_pages":["lxxviii","xciv","181","226"],"figures":["E-28(a)","E-46(a)","7-5(a)","7-36(a)"]}],"supported_claim":"NIST\u2019s later observed schematics revise local retained stems and opening boundaries shown by FEMA. Gray regions mean damage cannot be determined; dashed cladding marks do not establish structural steel failure.","recommended_correction":"10 panel identities now incorporate reviewed, bounded NIST contour revisions. Original FEMA polygons remain archived, each operation records its source pixels and scope, and all other panel contours remain unchanged. 264 independent NIST source-witness rays pass through the emitted geometry at two datums and two representations.","limitation":"This is a mixed FEMA/NIST schematic reconstruction, not the calculated finite-element exterior mesh or a complete measured 3D survey. Only reviewed local differences are changed. Unresolved gray regions and smaller endpoint differences remain recorded; line thickness and registration limit precision.","code_references":["site/js/exterior-panels.js","site/data/exterior_panels.json","site/js/damage-evidence.js"],"current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"verification":{"verification_date":"2026-09-07","verification_method":"Original report readback, registered source comparison and production geometry checks.","result":"10 panel identities now incorporate reviewed, bounded NIST contour revisions. Original FEMA polygons remain archived, each operation records its source pixels and scope, and all other panel contours remain unchanged. 264 independent NIST source-witness rays pass through the emitted geometry at two datums and two representations.","artifact_or_test_reference":["analysis/nist-panel-crosscheck/README.md","analysis/nist-panel-crosscheck/applied-amendments.json","analysis/nist-panel-crosscheck/geometry-verification.json"],"remaining_limitation":"This is a mixed FEMA/NIST schematic reconstruction, not the calculated finite-element exterior mesh or a complete measured 3D survey. Only reviewed local differences are changed. Unresolved gray regions and smaller endpoint differences remain recorded; line thickness and registration limit precision."}},{"id":"EVID-003","priority":"P1","title":"Observed exterior geometry and calculated exterior cases are distinct","evidence_category":["observed_schematic","simulation_result","application_behavior"],"checked_sources":[{"source_id":"NCSTAR1-2","printed_pages":["lxxviii","lxxxv","xciv","c","ci"],"figures":["E-28","E-36","E-46","E-54"]}],"supported_claim":"E-28(a) and E-46(a) are observed schematics; parts(b) are base-case calculations. E-36 and E-54 are more-severe-case calculations. The report describes local calculated exterior failure differences between cases.","recommended_correction":"Both routes explicitly state that the rendered exterior follows observational evidence in both cases, while the selector changes calculated interior damage. Original observed and case-matched calculated exterior figures are available separately in the shared evidence controls and exports record the policy.","limitation":"The viewer does not reproduce case-specific calculated exterior meshes. NIST\u2019s schematic observations and numerical predictions are not interchangeable historical records.","code_references":["site/js/exterior-panels.js","site/data/exterior_panels.json","site/js/damage-evidence.js"],"current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"verification":{"verification_date":"2026-09-07","verification_method":"Original report readback, registered source comparison and production geometry checks.","result":"Both routes explicitly state that the rendered exterior follows observational evidence in both cases, while the selector changes calculated interior damage. Original observed and case-matched calculated exterior figures are available separately in the shared evidence controls and exports record the policy.","artifact_or_test_reference":["site/js/damage-evidence.js","site/js/exterior-panels.js","tools/check_nist_panel_amendments.mjs"],"remaining_limitation":"The viewer does not reproduce case-specific calculated exterior meshes. NIST\u2019s schematic observations and numerical predictions are not interchangeable historical records."}},{"id":"APP-013","priority":"P1","title":"Isolated panel inspection displays a cropped source extent","evidence_category":["application_behavior","source_limit"],"checked_sources":[],"supported_claim":"The shared exterior emitter clips source panels to WTC1 floors92.4\u201399.4 or WTC2 floors78\u201385.4, including in isolated inspection. Some identified assemblies extend beyond that extent.","recommended_correction":"The selected-panel explanation labels the displayed impact-band crop. The camera frames retained steel and excludes nonphysical uncertainty outlines from its bounds. A cropped edge does not imply a historical fracture or a complete retained assembly.","limitation":"The isolated view still shows the shared cropped geometry. Source schematics must be consulted for portions beyond the displayed extent.","code_references":["site/js/exterior-panels.js","site/data/exterior_panels.json","site/js/damage-evidence.js"],"current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"verification":{"verification_date":"2026-09-07","verification_method":"Original report readback, registered source comparison and production geometry checks.","result":"The selected-panel explanation labels the displayed impact-band crop. The camera frames retained steel and excludes nonphysical uncertainty outlines from its bounds. A cropped edge does not imply a historical fracture or a complete retained assembly.","artifact_or_test_reference":["analysis/nist-panel-crosscheck/renderer-review.md","site/js/main.js"],"remaining_limitation":"The isolated view still shows the shared cropped geometry. Source schematics must be consulted for portions beyond the displayed extent."}},{"id":"GEO-007","priority":"P1","evidence_category":["published_calculation","representative_geometry"],"code_references":["analysis/structural-expansion-v6/core/core-column-symbol-review.json","analysis/structural-expansion-v6/truss-inventory/core-peer/independent-symbol-verification.json","site/data/truss_layout.json"],"title":"Numeric core workpoints have explicit source-level limits","checked_sources":[{"source_id":"LERA-WORKPOINTS","printed_pages":[]}],"supported_claim":"The lower model now uses all 47 numeric column workpoints from the LERA 97th\u2013100th-floor worksheet for each tower. Separate source grids apply at 107, 108, 109 and 110. The South core beam trace was re-registered to its numeric workpoints while preserving its source topology.","recommended_correction":"The lower grid is a prototype on floors 1\u201396 and 101\u2013106. The exact transition to the changed upper workpoints, within-story splices, centroid offsets and fabricated beam-column joints remain unresolved. Registered drawing geometry is not an as-built survey.","limitation":"The lower grid is a prototype on floors 1\u201396 and 101\u2013106. The exact transition to the changed upper workpoints, within-story splices, centroid offsets and fabricated beam-column joints remain unresolved. Registered drawing geometry is not an as-built survey.","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"verification":{"verification_date":"2026-09-11","verification_method":"Accuracy-note reconciliation against current production data, existing source/mesh review records and the September 11 release checks. Not a new independent measurement of every source drawing.","result":"The lower model now uses all 47 numeric column workpoints from the LERA 97th\u2013100th-floor worksheet for each tower. Separate source grids apply at 107, 108, 109 and 110. The South core beam trace was re-registered to its numeric workpoints while preserving its source topology.","artifact_or_test_reference":["tools/build_core_coordinates.py","site/data/truss_layout.json","analysis/core-comprehensive-review/README.md","analysis/release-model-review/README.md","analysis/view-integration-verification.json"],"remaining_limitation":"The lower grid is a prototype on floors 1\u201396 and 101\u2013106. The exact transition to the changed upper workpoints, within-story splices, centroid offsets and fabricated beam-column joints remain unresolved. Registered drawing geometry is not an as-built survey."}},{"id":"INT-015","priority":"P1","evidence_category":["published_calculation","representative_geometry"],"code_references":["analysis/structural-expansion-v6/core/check_retained_renderer.mjs","analysis/structural-expansion-v6/core-reconstruction.log","site/data/core_column_deformation.json"],"title":"Retained core-column pieces follow projected NIST calculations","checked_sources":[{"source_id":"NCSTAR1-2","printed_pages":["182","204","227","249"],"figures":["7-6","7-21","7-37","7-51"]}],"supported_claim":"All 24 tower/case/column entries classified as severed in the selected NIST cases have reviewed retained geometry: 56 separate pieces. Source samples, section assignments and piece identities remain in the records. Touching or overlapping pieces in projection do not establish physical load continuity.","recommended_correction":"The source elevation resolves one projected displacement component. Unmeasured transverse displacement, exact fracture surfaces and local plate tearing remain unresolved. Some visible ends are limited by obscuration rather than established fractures. These paths are calculated impact-case results, not an observational interior survey.","limitation":"The source elevation resolves one projected displacement component. Unmeasured transverse displacement, exact fracture surfaces and local plate tearing remain unresolved. Some visible ends are limited by obscuration rather than established fractures. These paths are calculated impact-case results, not an observational interior survey.","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"verification":{"verification_date":"2026-09-11","verification_method":"Accuracy-note reconciliation against current production data, existing source/mesh review records and the September 11 release checks. Not a new independent measurement of every source drawing.","result":"All 24 tower/case/column entries classified as severed in the selected NIST cases have reviewed retained geometry: 56 separate pieces. Source samples, section assignments and piece identities remain in the records. Touching or overlapping pieces in projection do not establish physical load continuity.","artifact_or_test_reference":["site/data/core_column_deformation.json","analysis/structural-expansion-v7/columns/emitted-witness-verification.json","analysis/release-model-review/README.md","analysis/view-integration-verification.json"],"remaining_limitation":"The source elevation resolves one projected displacement component. Unmeasured transverse displacement, exact fracture surfaces and local plate tearing remain unresolved. Some visible ends are limited by obscuration rather than established fractures. These paths are calculated impact-case results, not an observational interior survey."}},{"id":"EXT-015","priority":"P1","evidence_category":["published_calculation","representative_geometry"],"code_references":["analysis/structural-expansion-v6/exterior/production-exterior-verification.json","site/data/exterior_fragments.json","site/js/exterior-exit-support.js"],"title":"Exit-wall support follows surviving inner steel","checked_sources":[{"source_id":"NCSTAR1-5A_final_ch9-appC","printed_pages":["386\u2013387"],"figures":["9-79"]}],"supported_claim":"WTC2 north-wall support queries prioritize retained inner spandrels and50in splice plates, including panel seams, before local column fragments. The retained outer web ofC254 does not establish an inner-face seat. The possibleF82 tear betweenC251\u2013252 is recorded as localized evidence without deleting the whole bay.","recommended_correction":"WTC2 north-wall support queries prioritize retained inner spandrels and50in splice plates, including panel seams, before local column fragments. The retained outer web ofC254 does not establish an inner-face seat. The possibleF82 tear betweenC251\u2013252 is recorded as localized evidence without deleting the whole bay.","limitation":"No actual modeled truss anchor lies in theC251\u2013259 exit region in the current inventory. The query fix does not prove a historical seat failure. TheF82 tear\u2019s impact attribution and exact contour are uncertain.","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"verification":{"verification_date":"2026-09-07","verification_method":"Independent source readback and current production geometry/state checks; exact test scope and source registrations are linked.","result":"WTC2 north-wall support queries prioritize retained inner spandrels and50in splice plates, including panel seams, before local column fragments. The retained outer web ofC254 does not establish an inner-face seat. The possibleF82 tear betweenC251\u2013252 is recorded as localized evidence without deleting the whole bay.","artifact_or_test_reference":["analysis/structural-expansion-v6/exterior/production-exterior-verification.json","site/data/exterior_fragments.json","site/js/exterior-exit-support.js"],"remaining_limitation":"No actual modeled truss anchor lies in theC251\u2013259 exit region in the current inventory. The query fix does not prove a historical seat failure. TheF82 tear\u2019s impact attribution and exact contour are uncertain."}},{"id":"INT-016","priority":"P1","evidence_category":["reference_geometry","source_limit"],"checked_sources":[{"source_id":"LERA-ARCHITECTURAL","printed_pages":[],"drawings":["A-A-148","A-A-150","A-A-151","A-A-153"]},{"source_id":"PANYNJ-12673","printed_pages":[]},{"source_id":"NCSTAR1-7","printed_pages":["27\u201331"]}],"check_method":{"kind":"current_data_and_existing_source_review"},"audit_status":"partial_reconstruction_with_recorded_limits","code_references":["site/data/stairwells.json"],"title":"Stair quantities distinguish reviewed flights from repetition","supported_claim":"The primary impact ranges contain 48 source-supported main-stair stories, 96 flights and 921 modeled risers: North departures 93\u201399 and South 77\u201385. The North Stair B direction and intermediate landing height are corrected. Across both towers, 54 of 644 displayed stair stories have source support; 590 use reference flights. The complete display contains 1,306 flights and 12,488 modeled risers.","limitation":"These are model quantities, not a historical stair inventory. Shared footprints are corroborated across drawings rather than independently measured on every floor. Equal risers and some dimensions remain assumptions; rails, doors, landing thickness, wall assemblies, stringers and structural trimming remain incomplete. Post-impact damage and passability are not reconstructed.","recommended_correction":"These are model quantities, not a historical stair inventory. Shared footprints are corroborated across drawings rather than independently measured on every floor. Equal risers and some dimensions remain assumptions; rails, doors, landing thickness, wall assemblies, stringers and structural trimming remain incomplete. Post-impact damage and passability are not reconstructed.","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"verification":{"verification_date":"2026-09-11","verification_method":"Accuracy-note reconciliation against current production data, existing source/mesh review records and the September 11 release checks. Not a new independent measurement of every source drawing.","result":"The primary impact ranges contain 48 source-supported main-stair stories, 96 flights and 921 modeled risers: North departures 93\u201399 and South 77\u201385. The North Stair B direction and intermediate landing height are corrected. Across both towers, 54 of 644 displayed stair stories have source support; 590 use reference flights. The complete display contains 1,306 flights and 12,488 modeled risers.","artifact_or_test_reference":["site/data/stairwells.json","analysis/wtc1-impact-stair-review/README.md","analysis/wtc1-impact-stair-review/verification.json","analysis/wtc2-stair-flight-review/README.md","analysis/wtc2-outer-stair-flight-review/README.md","analysis/release-model-review/README.md","analysis/view-integration-verification.json"],"remaining_limitation":"These are model quantities, not a historical stair inventory. Shared footprints are corroborated across drawings rather than independently measured on every floor. Equal risers and some dimensions remain assumptions; rails, doors, landing thickness, wall assemblies, stringers and structural trimming remain incomplete. Post-impact damage and passability are not reconstructed."}},{"id":"INT-017","priority":"P1","evidence_category":["reference_geometry","source_limit"],"checked_sources":[{"source_id":"PANYNJ-12673","printed_pages":[]},{"source_id":"LERA-ARCHITECTURAL","printed_pages":[]},{"source_id":"NCSTAR1-7","printed_pages":["32\u201334"]}],"check_method":{"kind":"current_data_and_existing_source_review"},"audit_status":"partial_reconstruction_with_recorded_limits","code_references":["site/data/elevators.json","site/data/stairwells.json"],"title":"Elevator identities and source footprints do not certify clearance","supported_claim":"All 99 physical elevator-car identities per tower remain represented. Source-reviewed impact-zone hoistways distinguish clear shaft walls from car outlines. South cars 12\u201323, including freight 17, have reviewed runway boundaries on 77\u201380; the model also distinguishes their termination and the separate machine/secondary levels.","limitation":"Other floor bands still use reference envelopes. Fifteen South 75\u201376 overlaps with those envelopes remain recorded; they do not establish clashes in the historical building. Doorways, equipment, wall construction, local pits and complete clearances remain unresolved.","recommended_correction":"Other floor bands still use reference envelopes. Fifteen South 75\u201376 overlaps with those envelopes remain recorded; they do not establish clashes in the historical building. Doorways, equipment, wall construction, local pits and complete clearances remain unresolved.","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"verification":{"verification_date":"2026-09-11","verification_method":"Accuracy-note reconciliation against current production data, existing source/mesh review records and the September 11 release checks. Not a new independent measurement of every source drawing.","result":"All 99 physical elevator-car identities per tower remain represented. Source-reviewed impact-zone hoistways distinguish clear shaft walls from car outlines. South cars 12\u201323, including freight 17, have reviewed runway boundaries on 77\u201380; the model also distinguishes their termination and the separate machine/secondary levels.","artifact_or_test_reference":["site/data/elevators.json","site/data/stairwells.json","analysis/wtc2-express-terminal-review/README.md","analysis/wtc2-floor76-approach-review/README.md","analysis/release-model-review/README.md","analysis/view-integration-verification.json"],"remaining_limitation":"Other floor bands still use reference envelopes. Fifteen South 75\u201376 overlaps with those envelopes remain recorded; they do not establish clashes in the historical building. Doorways, equipment, wall construction, local pits and complete clearances remain unresolved."}},{"id":"INT-018","priority":"P1","evidence_category":["reference_geometry","source_limit"],"checked_sources":[{"source_id":"PANYNJ-12673","printed_pages":[],"drawings":["A-B-141","A-B-143","A-B-145","A-AB-211"]}],"check_method":{"kind":"current_data_and_existing_source_review"},"audit_status":"partial_reconstruction_with_recorded_limits","code_references":["site/data/core_floor_plan.json","site/data/elevators.json"],"title":"South terminal and transfer levels retain an explicit datum conflict","supported_claim":"Floor-80 secondary plates use concrete top +1 ft 10 in; shuttle overhead limits use +1 ft 6 in. The bounded floor-81 machine-room plates use provisional concrete top \u22121 ft 3\u00be in from the floor-specific plan. The typical section instead implies \u22121 ft 9 in.","limitation":"The floor-81 difference remains unresolved with 0.5 ft vertical uncertainty; plate thickness is provisional. Main-area plates do not include complete access, ramps, equipment or support construction. Floor-82 transfer headroom, doors and soffits remain unresolved.","recommended_correction":"The floor-81 difference remains unresolved with 0.5 ft vertical uncertainty; plate thickness is provisional. Main-area plates do not include complete access, ramps, equipment or support construction. Floor-82 transfer headroom, doors and soffits remain unresolved.","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"verification":{"verification_date":"2026-09-11","verification_method":"Accuracy-note reconciliation against current production data, existing source/mesh review records and the September 11 release checks. Not a new independent measurement of every source drawing.","result":"Floor-80 secondary plates use concrete top +1 ft 10 in; shuttle overhead limits use +1 ft 6 in. The bounded floor-81 machine-room plates use provisional concrete top \u22121 ft 3\u00be in from the floor-specific plan. The typical section instead implies \u22121 ft 9 in.","artifact_or_test_reference":["site/data/core_floor_plan.json","site/data/elevators.json","analysis/wtc2-express-terminal-review/README.md","analysis/wtc2-stair-transition-review/README.md","analysis/release-model-review/README.md","analysis/view-integration-verification.json"],"remaining_limitation":"The floor-81 difference remains unresolved with 0.5 ft vertical uncertainty; plate thickness is provisional. Main-area plates do not include complete access, ramps, equipment or support construction. Floor-82 transfer headroom, doors and soffits remain unresolved."}},{"id":"INT-019","priority":"P1","evidence_category":["reference_geometry","source_limit"],"checked_sources":[{"source_id":"NCSTAR1-6","printed_pages":[]},{"source_id":"NCSTAR1-6C","printed_pages":[]}],"check_method":{"kind":"current_data_and_existing_source_review"},"audit_status":"partial_reconstruction_with_recorded_limits","code_references":["site/index.html","site/js/north-sequence.js","site/js/south-sequence.js"],"title":"Onset motion illustrates source states without solving collapse","supported_claim":"The tower sequences distinguish observed exterior damage, selected calculated interior states, published floor/wall results and reconstructed transitions. The animation stops at a chosen 2\u00b0 tilt. It is an educational geometric illustration.","limitation":"The sequence does not solve coupled structural or thermal response, calculate stresses or connection failures, calibrate elapsed time, or calculate the subsequent collapse. The chosen 2\u00b0 endpoint is not a measured frame; holding lower floors in place is a display choice. Observed and calculated results must not be treated as interchangeable.","recommended_correction":"The sequence does not solve coupled structural or thermal response, calculate stresses or connection failures, calibrate elapsed time, or calculate the subsequent collapse. The chosen 2\u00b0 endpoint is not a measured frame; holding lower floors in place is a display choice. Observed and calculated results must not be treated as interchangeable.","current_code_status":"partly_addressed_with_recorded_limit","post_integration_verified":true,"verification":{"verification_date":"2026-09-11","verification_method":"Accuracy-note reconciliation against current production data, existing source/mesh review records and the September 11 release checks. Not a new independent measurement of every source drawing.","result":"The tower sequences distinguish observed exterior damage, selected calculated interior states, published floor/wall results and reconstructed transitions. The animation stops at a chosen 2\u00b0 tilt. It is an educational geometric illustration.","artifact_or_test_reference":["site/index.html","site/js/north-sequence.js","site/js/south-sequence.js","analysis/release-model-review/README.md","analysis/release-model-review/README.md","analysis/view-integration-verification.json"],"remaining_limitation":"The sequence does not solve coupled structural or thermal response, calculate stresses or connection failures, calibrate elapsed time, or calculate the subsequent collapse. The chosen 2\u00b0 endpoint is not a measured frame; holding lower floors in place is a display choice. Observed and calculated results must not be treated as interchangeable."}}],"evidence_category_definitions":{"application_behavior":"Observed behavior or data flow in the code snapshot reviewed by an original auditor.","drawing_transcription":"Project transcription of drawing information; accuracy and datum depend on verification of the original drawing.","estimated":"A region or quantity explicitly estimated by the cited source.","geometric_inference":"A calculated placement or intersection used for visualization, not an observed historical failure.","geometric_registration":"Calibration of source coordinates onto the model coordinate system.","insufficient_information":"The source explicitly lacks enough information to assign a definite state.","model_input":"An assumption or condition supplied to a source analysis model.","observed_schematic":"A source diagram representing observations with schematic boundaries and stated exceptions.","observed_summary":"An aggregate source summary of observations, not a complete member-level geometry.","physical_evidence":"Recovered material or other directly examined physical evidence, subject to identification and provenance limits.","reference_geometry":"A typical or reference dimension, not a complete member-specific as-built schedule.","reference_model_categorization":"A source classification of representative framing or analysis regions.","simulation_result":"A result calculated by a cited analysis, not a directly observed failure inventory.","source_figure_mapping":"Association of source labels or regions with model coordinates or identities.","source_limit":"An explicit evidentiary or source-completeness limit."},"coverage_review":{"date":"2026-09-11","finding":"Independent impact-zone architectural reviews supplement repeated structural beam prototypes. Source-supported stair flights are concentrated in the impact ranges. Missing structure is an omission, not evidence of destruction.","direct_core_floor_plans":{"wtc1":[96],"wtc2":[77]},"detailed_framing_deformation_floors":{"wtc1":[94,95,96],"wtc2":[79,80,81,82]},"detailed_concrete_deck_profiles":{"wtc1":[95,96],"wtc2":[80,81]},"id_maintenance":"Renumbered the newer duplicate INT-010/INT-011 entries to INT-013/INT-014; original connection and core-deflection IDs are unchanged.","integrated_core_prototype_floors":{"wtc1":[92,93,94,95,96,97,98,99,100],"wtc2":[77,78,79,80,81,82,83,84,85]},"remaining_core_floor_gaps":["The lower grid is a prototype on floors 1\u201396 and 101\u2013106. The exact transition to the changed upper workpoints, within-story splices, centroid offsets and fabricated beam-column joints remain unresolved. Registered drawing geometry is not an as-built survey.","Core beams repeat the floor-96 North and partial floor-77 South prototypes. Exact sections, joints, trimming around revised openings, reinforcement and core deck remain unresolved. The core slab retains a 4.5-inch/5-inch thickness conflict.","North elevators 6/7/50 clear faces and adjacent services, smaller South openings, floor-81 machine elevation and floor-82 transfer headroom remain unresolved. Typical plan-reading uncertainty is approximately 0.75\u20131 ft for the reviewed circulation geometry; each source registration retains its own uncertainty. A small control-fit residual is not a construction tolerance. Aperture polygon counts can include clipped fragments and are not counts of historical openings.","The floor-81 difference remains unresolved with 0.5 ft vertical uncertainty; plate thickness is provisional. Main-area plates do not include complete access, ramps, equipment or support construction. Floor-82 transfer headroom, doors and soffits remain unresolved."],"stair_flights":{"impactSourceSupportedStories":48,"impactFlights":96,"impactModeledRisers":921,"wholeTowerStories":644,"wholeTowerSourceSupportedStories":54,"wholeTowerReferenceStories":590,"wholeTowerModeledFlights":1306,"wholeTowerModeledRisers":12488,"quantitiesAreHistoricalInventory":false},"retained_core_columns":{"profiles":24,"pieces":56},"matched_core_beams":{"floorCaseProfiles":13,"matchedIntervals":33,"verticalDisplacementResolved":false}},"panel_review":{"changed_panels":10,"source_witness_rays":264,"changed_panel_ids":["WTC1-N-C114-116-F95.4-98.4","WTC1-N-C117-119-F94.4-97.4","WTC2-S-C414-416-F80.4-83.4","WTC2-S-C417-419-F79.4-82.4","WTC2-S-C432-434-F76.4-79.4","WTC2-S-C411-413-F81.4-84.4","WTC2-S-C423-425-F77.4-80.4","WTC2-S-C429-431-F78.4-81.4","WTC2-S-C426-428-F76.4-79.4","WTC2-S-C435-437-F77.4-80.4"],"full_nist_exterior_mesh_reproduced":false,"report":"analysis/nist-panel-crosscheck/README.md"},"public_notes":{"summary":"An educational reconstruction from original plans, observed damage schematics and published calculations. Impact-zone circulation has the strongest detailed coverage; many other floors and construction details use reference geometry. This is not a complete 1:1 model of September 2001 conditions.","sections":[{"id":"impact-core-coverage","title":"Impact-floor cores and circulation","paragraphs":["WTC 1 floors 92\u2013100 and WTC 2 floors 77\u201385 have differentiated aperture profiles. Reviewed hoistways, stair openings and service areas replace prototype geometry only within their source masks. Tower B uses independent original drawings, including raised floor-80 secondary plates and depressed floor-81 machine-room plates. The North 80-span and South partial 158-span beam prototypes remain separate from this architectural review.","North elevators 6/7/50 clear faces and adjacent services, smaller South openings, floor-81 machine elevation and floor-82 transfer headroom remain unresolved. Typical plan-reading uncertainty is approximately 0.75\u20131 ft for the reviewed circulation geometry; each source registration retains its own uncertainty. A small control-fit residual is not a construction tolerance. Aperture polygon counts can include clipped fragments and are not counts of historical openings.","Floor-80 secondary plates use concrete top +1 ft 10 in; shuttle overhead limits use +1 ft 6 in. The bounded floor-81 machine-room plates use provisional concrete top \u22121 ft 3\u00be in from the floor-specific plan. The typical section instead implies \u22121 ft 9 in. The floor-81 difference remains unresolved with 0.5 ft vertical uncertainty; plate thickness is provisional. Main-area plates do not include complete access, ramps, equipment or support construction. Floor-82 transfer headroom, doors and soffits remain unresolved."],"links":[{"href":"../data/core_floor_plan.json","label":"Core profiles, openings and source readings"},{"href":"../data/elevators.json","label":"Elevator sources and terminal limits"}]},{"id":"stair-coverage","title":"Stairs: quantity and source coverage","paragraphs":["The primary impact ranges contain 48 source-supported main-stair stories, 96 flights and 921 modeled risers: North departures 93\u201399 and South 77\u201385. The North Stair B direction and intermediate landing height are corrected. Across both towers, 54 of 644 displayed stair stories have source support; 590 use reference flights. The complete display contains 1,306 flights and 12,488 modeled risers.","These are model quantities, not a historical stair inventory. Shared footprints are corroborated across drawings rather than independently measured on every floor. Equal risers and some dimensions remain assumptions; rails, doors, landing thickness, wall assemblies, stringers and structural trimming remain incomplete. Post-impact damage and passability are not reconstructed.","Other floor bands still use reference envelopes. Fifteen South 75\u201376 overlaps with those envelopes remain recorded; they do not establish clashes in the historical building. Doorways, equipment, wall construction, local pits and complete clearances remain unresolved."],"links":[{"href":"../data/stairwells.json","label":"Stair flight records and uncertainties"}]},{"id":"structure-coverage","title":"Framing, coordinates and retained steel","paragraphs":["The lower model now uses all 47 numeric column workpoints from the LERA 97th\u2013100th-floor worksheet for each tower. Separate source grids apply at 107, 108, 109 and 110. The South core beam trace was re-registered to its numeric workpoints while preserving its source topology. The lower grid is a prototype on floors 1\u201396 and 101\u2013106. The exact transition to the changed upper workpoints, within-story splices, centroid offsets and fabricated beam-column joints remain unresolved. Registered drawing geometry is not an as-built survey.","Core aperture profiles cover WTC 1 floors 92\u2013100 and WTC 2 floors 77\u201385. The renderer retains 12 tabulated core-column deflection profiles, 66 damage-table rows and 658 story-column section assignments. Of those assignments, 216 use representative wide-flange dimensions and 7 are partly dimensioned; explicit box exceptions remain. Architectural opening detail does not establish complete structural framing. Core beams repeat the floor-96 North and partial floor-77 South prototypes. Exact sections, joints, trimming around revised openings, reinforcement and core deck remain unresolved. The core slab retains a 4.5-inch/5-inch thickness conflict.","All 24 tower/case/column entries classified as severed in the selected NIST cases have reviewed retained geometry: 56 separate pieces. Source samples, section assignments and piece identities remain in the records. Touching or overlapping pieces in projection do not establish physical load continuity. The source elevation resolves one projected displacement component. Unmeasured transverse displacement, exact fracture surfaces and local plate tearing remain unresolved. Some visible ends are limited by obscuration rather than established fractures. These paths are calculated impact-case results, not an observational interior survey.","Thirty-three individually matched core-beam intervals across 13 floor/case profiles follow published bent plan paths. Other spans retain their footprint-based reconstruction. Vertical displacement is unresolved; traced paths stay at the reference beam height, with representative sections and connections."],"links":[{"href":"../data/truss_layout.json","label":"Coordinate sources and prototype policy"},{"href":"../data/core_column_deformation.json","label":"Core-column source curves and retained pieces"},{"href":"../research/analysis/structural-expansion-v7/slabs/core-framing-evidence-inventory.json","label":"Earlier framing evidence inventory"}]},{"id":"whole-tower-coverage","title":"Whole-tower coverage and historical conditions","paragraphs":["All 220 story heights agree with the original LERA floor_heights.txt transcription. Floor geometry uses cumulative story elevations with floor 1 as its local reference. Roof elevations and the top of the floor-110 schedule band are separate quantities; the model is not based on uniform story spacing.","Lobby, mechanical, hat-truss, roof and foundation areas include separate source-reviewed components, but coverage is uneven. Complete upper-floor architectural surfaces, sublevel framing and foundation assemblies remain partial. Special zones should not be inferred from ordinary-floor repetition.","Original design drawings and September 2001 conditions are different evidence states. Later tenant alterations, openings and closures have not been comprehensively reconciled. Detailed geometry, successful tests and drawing-fit residuals do not provide an overall accuracy percentage."],"links":[{"href":"../data/floor_heights.json","label":"Story-height schedule"},{"href":"../data/tower-plan-verification.json","label":"September 11 schedule and plan checks"}]},{"id":"motion-coverage","title":"Observed damage, calculations and animation","paragraphs":["The tower sequences distinguish observed exterior damage, selected calculated interior states, published floor/wall results and reconstructed transitions. The animation stops at a chosen 2\u00b0 tilt. It is an educational geometric illustration.","The sequence does not solve coupled structural or thermal response, calculate stresses or connection failures, calibrate elapsed time, or calculate the subsequent collapse. The chosen 2\u00b0 endpoint is not a measured frame; holding lower floors in place is a display choice. Observed and calculated results must not be treated as interchangeable.","The base and more-severe case selector changes calculated interior damage. Both cases retain the observed exterior reconstruction; the separate calculated exterior figures are comparison evidence. A footprint intersection or missing modeled piece is not proof of an individual historical fracture."],"links":[{"href":"../index.html?view=initiation","label":"Tower sequence and source-state explanations"}]}]}}