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Despite bleed air failure and multiple system shutdown, bleed air system not blamed in crash

Now that its investigation is complete, the USAF has come back and handed down its decision on what caused the pilot of an F-22 Raptor to crash his aircraft in November 2010. According to sources and other pilots, the issue that led to the death of Capt. Jeff "Bong" Haney was a malfunction of the Raptor's bleed air intakes.
 
The report has now been issued and according to the USAF Accident Investigation Board, the cause of the accident was Haney, not the malfunctioning bleed air system in the stricken Raptor. The AIB found that while the bleed air system on the F-22 had failed, Haney didn’t react quickly enough to save the aircraft.
 
President of the AIB, Brig. Gen. James Browne wrote in the AIB report, "I find the cause of the mishap was the MP's [mishap pilot] failure to recognize and initiate a timely dive recovery due to channelized attention, breakdown of visual scan and unrecognized spatial disorientation."
 
Fingers were pointed early on at a failure of the On-board Oxygen Generating System or OBOGS as a cause of the accident. The accident report has determined that the OBOGS was functioning and was not a contributing factor to the accident. However, the OBOGS did shut down due to the bleed air problem the F-22 encountered.
 
The report read, "The MP most likely experienced a sense similar to suffocation." Despite that statement, the report also rules out hypoxia as a contributing factor to the accident. The report continues, "Due to the high affinity of oxygen to hemoglobin, the MP would have had adequate blood oxygen supply after the OBOGS failed. It was concluded that the late recognition of the MA's [mishap aircraft's] unusual attitude and appropriate corrective actions attempted by the MP demonstrates that hypoxia was not a factor in this mishap."
 
Defense News cites a source that claims that Haney would not have succumbed to hypoxia fully, though he would have had symptoms. The source notes that the hypoxia would have been a contributing factor even if the pilot were still conscious. Along with the OBOGS system on the stricken Raptor, the environmental control system, air cycle system, and On-board Inert Gas Generating System as well as cabin pressure were also shut down.
 
The recovered aircraft memory unit reportedly showed that the "partial pressure to the MP's [mishap pilot] oxygen stopped shortly after 19:42:37 L, which would lead to severely restricted breathing."
 
Haney was conscious enough to attempt to recover from the steep dive his Raptor was in right before the crash. The F-22 hit the ground three seconds after Haney first attempted to recover. The report notes that for 39 seconds Haney did nothing to address the flight condition of his aircraft.
 
The report reads, "The fact that the [mishap pilot] went from a controlled flight regime to an unusual attitude and did not take corrective actions for 30 seconds suggests he had unrecognized spatial disorientation. At 19:42:24L the [mishap pilot] recognized the [mishap aircraft's] position and attempted to perform a dive recovery."
 
This was the second F-22 lost in service since the aircraft went operational. In March of 2009, another Raptor crashed killing the pilot. This accident was a contributing factor to the Raptor stand down that lasted months.
 
This week the final F-22 Raptor rolled off the assembly line and will replace the aircraft lost in the fatal crash that took Haney's life.

Source: Defense News



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i guess
By Bubbacub on 12/16/2011 8:53:07 AM , Rating: 5
its not allowed for the machine to be responsible for a crash.

ffs the poor pilot had a restricted oxygen supply (how restricted and the depth of an individual's response is arguable) due to mechanical error.

no mechanical error means no reduction in o2 supply = no "loss of spatial awareness" = no crash

the key error appears to be mechanical in my eyes. the AF need to admit this and correct it - not paper over the cracks and blame the pilot




RE: i guess
By Brandon Hill (blog) on 12/16/2011 9:11:55 AM , Rating: 3
quote:
the key error appears to be mechanical in my eyes. the AF need to admit this and correct it - not paper over the cracks and blame the pilot


You should watch the HBO TV movie "Afterburn" about wire chaffing in the F-16.

http://en.wikipedia.org/wiki/Afterburn_(film)


RE: i guess
By bigdawg1988 on 12/16/2011 9:34:23 AM , Rating: 5
the AF need to admit this and correct it - not paper over the cracks and blame the pilot

I've heard that when the pilot dies, the pilot is to blame, especially for new aircraft. Maybe that has changed, but somehow I doubt it. You think the AF is going to say the aircraft they spent billions developing and testing actually has potential flaws that lead to a pilot's death? Not on this planet.


RE: i guess
By Reclaimer77 on 12/16/2011 8:51:11 PM , Rating: 1
The F-22 is NOT fatally flawed though. Oxygen generation systems have been used for a LONG time. There's nothing mysterious here or a conspiracy. This was just a malfunction which could happen in ANY system.


RE: i guess
By fteoath64 on 12/18/2011 12:51:03 AM , Rating: 2
You are right!. With the amount of secrecy involved with each sub-contractor, there is UNLIKELY any redundancy because that would compromise their precious security protocols. Then, how can they eject a single sub-con from the project ???. None, Zilch!.
You can see the weakness because of that stupid secrecy. Besides, every sub-con will not disclose any limitations of their systems for fear of being singled out. So expect holes upon holes of bugs in those systems. A human who cannot compensate for those will die.

You see, they live by the sword and will die by the same sword!. Hey, blaming a dead human is easier si they did.


RE: i guess
By MrBlastman on 12/16/2011 11:29:56 AM , Rating: 3
This whole incident reminds me of the Ted Harduvel F-16 incident where the Air Force blaimed it all on him for the jet crashing rather than an electrical system malfunction (which was later proved) to have been the cause. What a fiasco.

The Air Force has to save face and is also protecting their own interests from a potential lawsuit here, that is all. Unfortunately, the incident in 1982 lead to a precedent from the courts (after his wife won a judgement against General Dynamics and the Air Force) which stated that the contractors that did work for the Military were an "extension" of the US Government which gives them immunity from being sued.

I'm not a fan of lawsuits at all but in this case, just thought I'd share for the younger readers who might not know the history behind these sorts of things.


RE: i guess
By Brandon Hill (blog) on 12/16/2011 11:44:32 AM , Rating: 2
See my post above ;)


Negative Dynamic Control
By simian pete on 12/16/2011 10:28:09 AM , Rating: 3
So if the pilot had enough time to correct (A BIG IF) even though he was experiencing "suffocation" then could the Raptor have other "aerodynamic" problems ?

Maybe Pilot induced oscillation or Oscillation induced by a faulty control system ? Maybe ? Or could the Raptor specs be overrated, flying outside it's "envelope" ( i.e. maybe 60,000 feet altitude is to high ?) ...

You just wonder what the heck is wrong -- Anyhow, I'm just speculating. Then Air Force engineers/technicians have mucho smarts. They will probably figure it all out ....

Once the bugs are solved they should build some more Raptors, like another 400 at least .... get the assembly line going again !




RE: Negative Dynamic Control
By rlandess on 12/16/2011 11:25:40 AM , Rating: 2
quote:
So if the pilot had enough time to correct (A BIG IF)


The article states that the pilot did nothing for 39 seconds. It seems to me that what they are saying is that the pilot failed to follow protocol and get to a safe altitude for 39 seconds, then took a steep dive in the last 3 seconds.

39 seconds is a long time.

I'm surprised pilots don't get an emergency air supply for flight testing. Then if the plane goes haywire or HAL tries to kill you you can just pop the mask on and concentrate on landing safely.


RE: Negative Dynamic Control
By Solandri on 12/16/2011 12:14:14 PM , Rating: 5
According to the report, he was at over 50,000 feet when the oxygen generator cut out and the plane lost pressure. At that altitude and pressure (about 1/10th sea level pressure), even breathing 100% oxygen you're having to cope with less than half the oxygen you get at sea level (equivalent to breathing unassisted at about 18,000 feet). Without supplemental oxygen, you'll be unconscious within 10-15 seconds.

It sounds like he did the correct thing in those seconds - point the plane down so he could get to an altitude where he'd have enough oxygen to stay awake. But the rest of the flight reads like he fell unconscious (little to no input to the controls), and only woke up a few seconds before the crash (7.5g recovery maneuver). It really does seem like a whitewashing by blaming the pilot for failing to do anything while he was most likely unconscious.


RE: Negative Dynamic Control
By Reclaimer77 on 12/16/11, Rating: -1
RE: Negative Dynamic Control
By voodoochile123 on 12/16/11, Rating: -1
RE: Negative Dynamic Control
By voodoochile123 on 12/19/11, Rating: -1
By inperfectdarkness on 12/18/2011 5:22:12 PM , Rating: 3
this. as a flyer myself, i've done altitude chamber testing, and i can personally vouch for the effects of hypoxia on a person at 30,000 feet (chamber pressure). considering i was breathing 100% oxygen for 20-30 minutes prior to this, the argument for hemoglobin being able to compensate for the lack of o2 is simply hogwash.

it's one thing if the pilot is performing a 9-g maneuver and blacks out & noses the plane into terrain. it's quite another if he's flying a fairly benign profile at 50,000' and the same thing happens. FL 500 is very, very close to the altitudes that u2's fly at...and i can also speak to the dangers of hypoxia on u2 pilots whose oxygen systems have malfunctioned. TUC (time of useful consciousness) at 50,000 feet is less than 10 seconds. 10 seconds is next to non-existent when you don't even instantly recognize your own hypoxia; especially when you're tasked with 1. trying to correct the oxygen deficiency, 2. trying to lose altitude so you can increase your TUC or breathe normally on cabin pressure, 3. task-saturated, which further reduces the useful duration of oxygen (resting will increase your TUC, while vigorous activity will reduce it).

i really do smell a cover-up here. sad. how many more pilots and f-22's (which we already have fewer than we need) will we have to lose before the real issues are fixed? yes, pilot error is a factor in a majority of mishaps (fatal or otherwise)...yet this still smacks of quite a bit more than the USAF is letting on about.


Autopilot ??
By KingofL337 on 12/16/2011 10:53:52 AM , Rating: 2
I'm surprised that an aircraft like the F22 doesn't have some form of autopilot / auto-descend. I know if I was suffocating I'd flip the switch and pray.




RE: Autopilot ??
By Brandon Hill (blog) on 12/16/2011 10:55:53 AM , Rating: 3
"I'm sorry Dave, I can't do that"


RE: Autopilot ??
By DoctorBeer on 12/16/2011 5:16:12 PM , Rating: 2
If I read this correctly...
By HoosierEngineer5 on 12/17/2011 11:11:00 AM , Rating: 2
At 19:42:24 the mishap pilot attempted to perform a dive recovery.

Slightly after 19:42:37, partial pressure to the pilot's oxygen stopped. If the F-22 hit the ground three seconds after the recovery was attempted, the oxygen system was working ten seconds after impact.

If the aircraft had already impacted the ground, I would expect the oxygen system to stop if the impact was severe enough.




RE: If I read this correctly...
By static1117 on 12/17/2011 12:52:03 PM , Rating: 2
Im not sure exactly how the oxygen system works on the F-22 as I have 12 years experience on F-16's, but when you lose bleed air, your lose alot of fuctions in the A/C.

1. Cabin pressure
2. G-Suit pressure
3. Cooling Air

and not paticularly in that order. Also, once you lose G-Suit pressure, you also lose the PBG (Pressure Breathing Group) function of the jet. (PGB is a function of the Oxygen regulator that, under G, forces air into the pilot. And I mean it FORCES air)

Not arguing for one side or another, just a little clarification


Link to the report
By Just Tom on 12/16/2011 10:17:07 AM , Rating: 3
http://usaf.aib.law.af.mil/ExecSum2011/F-22A_AK_16...

One thing that must be stressed is the report does not whitewash the failure, it simply states the failure should not have been fatal.




The Dead
By gevorg on 12/16/2011 1:20:48 PM , Rating: 2
Blaming the dead is quite common in aircraft crashes.




Should not have caused a crash.
By Einy0 on 12/18/2011 12:50:44 PM , Rating: 2
I worked on the F-15E for a number of years and it was not unheard of for the Oxygen system to fail. The thing is the pilot or aircrew on F-15Es get a failure indication and sometimes an audible warning depending on the system failure. This warning would be immediately sounded, etc... The protocol is for the pilot to descend ASAP. If they don't descend they will black out within 30 secs to a minute. The flight recorder would have made note of the time that alarm was sounded and when a life saving dive was initiated. Apparently they felt under the circumstances the pilot should have been able to descend in time and avoid blacking out. I say it's partially mechanical failure and partially pilot error unless the warning system failed to indicate that his oxygen system had failed. If that is the case there will be another crash and they won't be able to cover that up.




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