B-2 crash near Guam? (Update: Post Crash Pics & Video)

reply to post by JohnnyR


Excuse me? That statement seems to be geared towards attacking someone. And even if its not me I don't feel its in good taste. As someone who is new to the forums with only 12 posts I'd be careful in the wording you choose to use and the tone in which you introduce your self to a new forum if you wish to be taken seriously.

(Aim well before Shooting your mouth off)

*Edited number of posts to reflect current amount lists in posters profile*

[edit on 6-6-2008 by Canada_EH]

Anyways to further the point of this thread and inform everyone of causes and other information. As far as I can tell it's possible that all the pilots had to do to avert the accident was turn on the pitot heat prior to performing air data calibrations. But this technique while suggested was not part of the physical cockpit checklist procedures.

The result of the moisture in the ports lead to the airspeed displayed to the pilots to be displayed as 150 knots while it actually was only 120 knots and a computer perceived negative angle of attack upon takeoff. This lead to the stall that Harlequin miss-interpreted as cause by moisture. The moistures roll was what lead to the take off at the incorrect airspeed and the over compensation of the aircraft control surfaces.

According to the report, this (the moisture) caused an, "uncommanded 30 degree nose-high pitch-up on takeoff, causing the aircraft to stall and its subsequent crash."

The wording of "uncommanded" makes me think that the nose up and take-off rotation wasn't even the input of the pilot. This implies that the aircraft flies by the computer more then the pilot and that there was no hope in recovering when the controls wouldn't respond correctly to the "probably" correct inputs from the pilot to put it back down on the runway in one piece. Instead due to the mixed info flowing to the controls you can see the right side air-brake fully deployed yet unable to right the aircraft due to the mix of other controls and movements due to the computers.

Reported as moisture here in this Austrailian link too.

American air force accident investigators have blamed moisture for the crash of a $US1.4 billion B-2 stealth bomber in Guam earlier this year.

Gemma Casas reports the US Air Force Accident Investigation Board says moisture distorted the information on the bomber's air data system, causing the flight control computers to calculate an inaccurate air speed and a negative angle of attack upon takeoff

www.radioaustralia.net.au...

Now reading Canada_EH post, this problem of moisture is known and fixable and yet isn't 'written down' ! Thats madness - if they knew it was a problem with an easy fix, why wasn't it a SOP ?

I think that the pilot simply forgot to lock his seat. I've seen a C-130 pic where the pilot didn't lock his seat and held the yoke while his seat rolled back. It's even happened to me in a Cessna 152 - luckily the instructor was there.

Or maybe it was a moisture problem. They did test this thing in the Mojave desert, after all. Can you imagine what the crew was thinking? "Nobody's ever ejected from a B-2, so we don't know it this will work or not. Here goes nothing!"

[edit on 10-6-2008 by HatTrick]

The GAO reported that this could be a problem back in 1997 in a report. They're lucky that it hasn't happened before now.

I watched the video, and the plane that crashed lifted off much earlier than the one before it, that little bit more distance could have created the lift needed to maintiain elevation.

The first plane, lifted off about where the white building is, second much sooner. Also notice the angle, that too is steeper than first one.

Just my opinion.

See video again, and investigation.

[edit on 11-6-2008 by ADVISOR]

The airspeed sensors were reading 30 knots faster than they were going. So they thought they were at 150 knots when they were at 120. And when they lifted off, the AOA showed negative in the flight control computer, so the system pitched them up to what it THOUGHT was the correct AOA for a normal take off but was actually 30 degrees.

More photos have surfaced of the B-2 crash site and the investigation and fire operations.
These ones surfaced at gizmodo.com and they give credit to a photographer named Joe Pappalardo. The image we saw earlier where not from an actual release from the Air Force but these ones are it appears.








Emergency response crews check explosives in ejection seat.

Also a Timeline of the accident is posted on the popularmechanics.com website. As far as I can tell it all seems pretty accurate. Also it high lights the fact that I dont think has been mentioned that there was no water in the instruments on take off. The ground crew had re-calibrated the computer to read correct with water in it so when the water was removed (with sensor heaters) the adjusted readings where incorrect on take off.

9:29 am /// Waterlogged /// During a preflight check, the pilot notices three air data sensors are malfunctioning. Unknown to the crew, water in the sensors is skewing the air-pressure readings too high.
9:34 am /// Recalibration /// A ground crewman, using a cockpit keyboard, recalibrates the three waterlogged sensors. The preflight checks continue, and the B-2 taxis to runway Zero-Six-Right.
10:29 am /// Boiling Sensors /// Before takeoff, the pilot turns on the sensors’ heaters. Water in the sensors evaporates; the readings are now normal, but the earlier fix skews air-pressure data too low.
10:30:12 am /// Slow Start /// The B-2 starts takeoff. The on-board flight computer displays the wrong airspeed, causing the pilot to lift off at 133 knots (153 mph) rather than the required 145 knots.
10:30:50 am /// Auto Override /// The flight computer, relying on bad air-pressure readings, concludes the aircraft is in a nose-low altitude and automatically raises the nose to 30 degrees.
10:31:06 am /// Fiery Ending /// The B-2, going too slowly, with its nose angled too high, stalls. As the airplane’s wing scrapes the runway, the pilot and commander safely eject. The B-2 crashes.

links:
www.popularmechanics.com...
gizmodo.com...



[edit on 15-7-2008 by Canada_EH]

reply to post by Canada_EH


Sorry bro..didn't actually notice this..read this post that said crashed but didn't see the updated pics part.