On February 23, 2008, a B-2A stealth bomber, tail number 89-0127, “Spirit of Kansas,” crashed on takeoff from Andersen Air Force Base, Guam. Both pilots ejected and survived. It was the first B-2 ever lost; the Air Force put the total loss at $1,407,006,920.
The Accident Investigation Board traced it to the air data system. The B-2’s flight control computers work out airspeed and angle of attack from air pressure measured by 24 port transducer units (PTUs) on the wing. Before the flight, an air data calibration was run by the book: each PTU is compared with the average of all 24, and any that is off by more than 0.05 inHg gets a correction stored in its memory. Three of the PTUs had moisture in them, so their corrections came out larger than necessary, differing from the other 21 sensors by as much as 0.262 inHg. When the crew switched on pitot heat for takeoff, a normal pre-takeoff step, the heat began removing the moisture, and the stored corrections now distorted the data. The cockpit showed about 10–12 knots more than the jet’s true speed; its takeoff roll was about 1,450 feet shorter and it lifted off 13 knots slower than the lead aircraft. At liftoff the computers calculated a negative angle of attack, read it as a dangerously nose-low attitude and commanded full nose-up: a 1.6 G pitch-up to 30 degrees. With all air data lost and airspeed falling, the jet stalled, rolled and yawed left, and the left wingtip hit the ground. The board found the crew could not have known about the error before the pitch-up and that their actions were reasonable and appropriate.
In 2006, during an earlier Guam deployment, system engineers had suggested turning on pitot heat before an air data calibration to evaporate moisture. It was used by many technicians but never written into the technical orders or lessons-learned reports, and the crew and the specialist on 23 February had not heard of it. The board listed that ineffective communication as a substantially contributing factor.
What you’re seeing: REAL FOOTAGE — the U.S. Air Force accident board’s ground-camera and security-camera videos of this jet’s takeoff and crash (released with the report in June 2008), upscaled with Topaz Video (Proteus, non-generative; no frames invented) and cropped to vertical; they are tagged ARCHIVE · RESTORED. REAL DOCUMENTS — pages 5, 10 and 19 of the board’s Summary of Facts, with the quoted sentences highlighted. RECONSTRUCTION — everything else is our own 3D reconstruction and schematics: the B-2 model is AI-generated from a USAF photo (Tripo3D), proportion-corrected to the published 172 ft span and 69 ft length, with generator-invented lettering removed, and is illustrative only; landing gear, runway and motion are simplified; sensor spot positions, chart values (except the 0.262 inHg maximum) and the port cutaway are schematic, not the real design. The narration voice and the music are AI-generated (Gemini TTS, Stable Audio). Facts come from the Air Force report.
Sources: U.S. Air Force Aircraft Accident Investigation Board Report, B-2A T/N 89-0127, Andersen AFB, Guam, 23 Feb 2008 (Executive Summary, Summary of Facts, Statement of Opinion; Air Combat Command, 5 June 2008).
#B2Spirit #AirForce #Aviation #Engineering #Shorts
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Source: USAF Accident Investigation Board report, B-2A 89-0127 (2008). Three of the four upper gust-load-alleviation PTUs took calibration corrections, which differed from the other 21 by as much as −0.262 inHg (Summary of Facts p.5). Turning on pitot heat for takeoff "began removing the moisture… reintroduced a disparity between PTU sensors" (Statement of Opinion p.24). Indicated airspeed ~12 kt above actual; takeoff roll 1,450 ft shorter and liftoff 13 kt slower than the lead (SoF p.6). The computed negative angle of attack "pitched the aircraft up in a manner the crew was unable to override" — "full nose-up," 1.6 G to 30° (SoF p.6). The pitot-heat technique was "never formalized in a technical order change" (SoF p.19). Both pilots survived.
I remember the story about World War II England wanted to use our bird launcher to test their windshield of their fighter jets so we sent it to him and their jets keep failing and they asked us what was wrong and we said thaw the bird out first. True story.
So 3 out of over 20 sensors gave different reading and the computer decides to listen to those odd numbers instead of the rest of the sensors? Redundancy is a key word when it comes to electronics. Looks like they had none. The people who designed the system are the real ones to blame.
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More complicated they are the easier is to screw them up. Problem with engineers they love to reinvent the wheel every time and thank everybody prior to them we’re idiots.
So two sensor f up plane and crue can't do anything congrats what a ingeneriing
But this billy bob baby boy couldn't get a kidney transplant from daddy's insurance 😢😅
That would have never happened with the B-52.
All that technology was defeated by water…..