Keep Factually independent
Whether you agree or disagree with our analysis, these conversations matter for democracy. We don't take money from political groups - even a $5 donation helps us keep it that way.
What investigations and official reports concluded the Pentagon was struck by a plane and how did they rule out alternative theories?
Executive summary
Multiple official investigations and contemporaneous reports concluded that American Airlines Flight 77 struck the Pentagon on Sept. 11, 2001; the 9/11 Commission, Department of Defense histories and engineering studies cite radar tracks, eyewitness accounts, security camera footage, recovered aircraft debris, and structural analyses to reach that conclusion [1] [2] [3]. Alternative theories—missile, no-plane, different aircraft, or staged demolition—have been repeatedly addressed and rejected in fact-checking, photographic and video releases, and engineering after‑action reports that explain observed damage patterns and recovered wreckage [4] [5] [6].
1. Official, large-scale inquiries that concluded a plane hit the Pentagon
The National Commission on Terrorist Attacks Upon the United States (the 9/11 Commission) produced a comprehensive narrative including Flight 77’s flight path, descent and impact; it cites radar data and controller observations placing the aircraft on a trajectory into the Pentagon and documents that the aircraft crashed into the building at about 9:37–9:38 a.m. [1]. The Department of Defense’s official Pentagon histories and after‑action publications likewise state that American Airlines Flight 77 struck the E Ring and describe the path of destruction inside the building [7] [2]. These institutional reports form the core documentary basis for the conclusion that a hijacked Boeing 757 struck the Pentagon [1] [7].
2. Engineering and structural analyses that match a jet impact to the damage
Independent and professional engineering studies — notably the American Society of Civil Engineers’ Building Performance Study (BPS) team — inspected the wreckage, measured damage (including the ~75-foot exterior opening), and used impact simulations to explain why the hole size and window survival patterns were consistent with a high‑speed jetliner strike and progressive structural failure rather than a small missile or cartoon outline of a plane [5] [3]. The ASCE BPS team and other structural engineers emphasized that wings and lighter components shear off on impact while heavy sections and fuel penetrate and propagate damage, accounting for observed destruction patterns [3] [8].
3. Physical and photographic evidence cited by investigators
Federal investigators released security camera footage and extensive photo collections showing an object striking the Pentagon and debris at the crash site; the FBI and other agencies made images and video available in archives used in later analyses and fact checks [4] [9] [10]. Journalistic and museum collections also document recovered aircraft fragments and shards identified as airplane wreckage that were cataloged by the FBI and the Armed Forces Medical Examiner’s Office during victim identification, which investigators cite in support of the aircraft-impact conclusion [9] [11] [12].
4. Eyewitness testimony and survivor accounts
Dozens of witnesses — Pentagon staff, delivery drivers, first responders and individuals in nearby offices — reported seeing a jetliner approach and strike the building; oral histories and survivor narratives are incorporated into Pentagon histories and contemporary news reporting [13] [14]. These firsthand reports corroborate the physical and radar evidence used by official inquiries [7] [2].
5. How investigators and fact‑checkers addressed alternative theories
Conspiracy claims — such as that a missile hit instead of a plane, that no debris was found, or that the hole was “too small” for a 757 — have been repeatedly examined and rebutted by engineering analyses, photo/video evidence, and fact‑checks. Popular Mechanics and other technical explainers detail why a crashing aircraft does not leave a full‑outline hole and cite ASCE measurements and simulations; fact‑check organizations and AP/AFP reviews point to security camera footage and released FBI photos showing plane impact and wreckage [5] [8] [4] [6]. Radio Free Asia and other fact checks note DoD-released flight‑path data and parking‑lot camera clips that counter “no wreckage/no witnesses” claims [15].
6. Disagreements, transparency limits, and persistent skepticism
While multiple official entities agree on the plane-impact conclusion, critics point to gaps, redactions or limited releases of raw materials as reasons for continued suspicion; recent reporting about Pentagon handling of classified material and selective disclosures in other contexts has fed broader skepticism about institutional transparency [16] [17]. But available sources show that the primary empirical bases cited by investigators — radar records, video, debris, structural analysis and eyewitness testimony — were presented in the formal accounts and in public archives used by journalists and fact‑checkers [1] [10] [6].
7. Bottom line for readers weighing claims
The weight of official investigations, engineering studies and contemporaneous imagery converges on the conclusion that American Airlines Flight 77 struck the Pentagon; fact‑checkers and technical teams have explained why the physical evidence and damage patterns are inconsistent with missile or no‑plane hypotheses [1] [3] [6]. At the same time, some public distrust persists due to selective classification and incomplete public releases in other Pentagon matters — a background that helps explain why alternative theories continue to circulate even after multiple rebuttals [16] [17]. Available sources do not mention some specific ancillary claims sometimes made by conspiracists; those claims should be assessed against the primary documentary and forensic records cited above [4] [7].