EVD-105
NIST NCSTAR 1: impact plus fire initiated collapse of WTC 1 and WTC 2
engineering reportofficial governmentauthenticoriginal
Provenance
- Source
- NIST NCSTAR 1 — Final Report on the Collapse of the World Trade Center Towers (2005)
- Date
- 2005-09-01
- Page
- NCSTAR 1, findings
- SHA-256
- 94186875ba614c17e8ab053fe7fb7a89b87266245aa9284fae4382306ae3429c
- Classification
- unclassified
- Copyright
- public domain
https://nvlpubs.nist.gov/nistpubs/Legacy/NCSTAR/ncstar1.pdf
Quality 3.88 / 5components retained
Prov5
Auth5
Ind2
Contemp2
Corr4
Spec5
Comp4
Chain4
Observation
NIST published a fire-and-impact initiation sequence for WTC 1 and WTC 2 in 2005.
Interpretation
Institutional conclusion. Independence is limited. Competing energetics claims are H004, not a silent overwrite.
Source text
INTERPRETATION (NIST, 2005): Aircraft impact dislodged fireproofing; fires heated remaining steel; floors sagged; perimeter columns bowed; collapse initiated at the impact stories and the mass above then overwhelmed the structure below. NIST (NCSTAR 1 §6.14.4) also states that the structure below the initiation level offered minimal resistance to the falling mass — a sentence alternative investigators read as compatible with additional energetic mechanisms. This item is the official H003 support. It is not an observation of a laboratory fire test of a 110-storey building.
Hypothesis linkage
NIST fire-and-impact initiation sequence.
NIST fire-and-impact sequence is a different mechanism family.