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Fatal Problems Continue To Plague F-22 Raptor
Hugh Pickens writes "The LA Times reports that even though the Air Force has used its F-22 Raptor planes only in test missions, pilots have experienced seven major crashes with two deaths, a grim reminder that the U.S. military's most expensive fighter jet, never called into combat despite conflicts in Iraq, Afghanistan and Libya, continues to experience equipment problems — notably with its oxygen systems. New details from an Air Force report last week drew attention to a crash in November 2010 that left Capt. Jeff Haney dead and raised debate over whether the Air Force turned Haney into a scapegoat to escape more criticism of the F-22. Haney 'most likely experienced a sense similar to suffocation,' the report said. 'This was likely [Haney's] first experience under such physiological duress.' According to the Air Force Accident Report, Haney should have leaned over and with a gloved hand pulled a silver-dollar-size green ring that was under his seat by his left thigh to engage the emergency system (PDF). It takes 40 pounds of pull to engage the emergency system. That's a tall order for a man who has gone nearly a minute without a breath of air, speeding faster than sound, while wearing bulky weather gear, says Michael Barr, a former Air Force fighter pilot and former accident investigation officer. 'It would've taken superhuman efforts on the pilot's behalf to save that aircraft,' says Barr. 'The initial cause of this accident was a malfunction with the aircraft — not the pilot.'"
Yeah, it sounds like whoever made these things and charged the government billions had really screwed up. Luckily, they are never going to get another multibillion dollar contract from the government, right? I mean, if they did, that could screw that one up just as badly, and then where would we be? We're lucky that we don't live in some communist country where arms manufacturers just get fat from the handouts of the government without any real accountability.
In mock combat the F-22 has had something like 1-100 kill ratios, so what air force could?
That only lasted a few days though. Then the next version of PunkBuster was released, and all those guys got banned.
The new systems are smaller and lighter. Also, at least from the original crash report, the oxygen system wasn't at fault. It shut down like it was supposed to (it was operated by bleed air from the engine, the ECS detected a hot bleed air leak and shut off the bleed air valves. If you don't check a hot bleed air leak, you can set the plane on fire or melt parts of it), but the pilot struggled to activate the emergency oxygen system and had significant difficulty with this due to the bulky gear he was wearing.
While struggling with activation of the EOS, he lost track of time and became disoriented, failed to notice that his aircraft attitude had changed, and attempted a dive recovery far too late to save himself.
In every case where aviation has been stretching the envelope, there have been accidents and fatalities. The GB Racer is a classic case of this. Many of the renown WWII aircraft had A versions that were anything but safe to fly.
The venerated F-16 wasn't much to write home about either when it was first released. The engineers will learn and get experience. It will come at a horrible price. But if you wanted to live a safe life, you shouldn't be in the military in the first place.
OBOGS isn't bleeding edge even F16s used them http://www.cobham.com/media/75388/SYSTEM%20F-16%20OBOGS%20ADV10556.pdf
This is just a case of poor design, the Eurofighter has Oxygen level warning system, the F22 doesn't. If you put the emergency O2 actuator in an ergonomically challenging position, what do you expect?
It seems like this should have been automatically switched on.
They plan to use them for decades, but they haven't used them at all yet. As the summary says, they've only been used for test missions so far.
The article says that there have been many cases of F22 pilots showing signs of hypoxia, and they grounded all craft earlier this year to run a study as to why. They didn't find or fix the problem, but started allowing people to fly them again. Now someone dies and they blame him rather than the faulty air supply. That's pretty damn low. I hope they keep all of these planes grounded now until the issue is resolved.
which is totally what she said
Oh for fuck's sake.
Pilots work out...a lot. A hell of a lot. They do a lot of strength exercises, including push-presses and other exercises that work the back, because in the course of these exercises they ALSO end up building up their legs. As a method of fighting black-out, they tense their legs to tighten the muscles and help push air up into their upper body (away from where it tends to go during positive high-g manuvers). Yes, there is the flight suit that squeezes them as well, but every bit counts. And since the ring that starts the emergency system is forward and beneath the pilot, that means that they would be using their back to pull against that 40-lb resistance...
Actually no, they're expected to twist and turn to reach the ring while held in place by an insanely tight harness. This ain't no Cessna. Further, they're then expected to pull the ring in a direction away from their body - it's stupidly designed in the most un-ergonomic way possible.
After a minute without air? That's what it feels like to be working out hard...and since he wouldn't have been exercising vigorously during that minute, he'd have had plenty of glucose on hand, so his muscles could easily have worked using anaerobic respiration long enough for one pull of a ring.
A minute without air? I have an idea. We put a stopwatch on you and make you hold your breath while sitting in a chair. I'll put a 40-lb weight with a pop-tab on top under the chair between your legs and we'll see if you can manage to reach down, find it, then lift it a couple inches after you hold your breath an entire minute. If you're even awake still. And that test STILL won't account for the vertigo and g-forces involved in the dive and attempting a dive recovery.
Furthermore, how is this supposed to be harder based on how fast you're moving? I fly in airplanes all the time, and I don't notice that it gets harder to lift things or move around based on how fast or slow the plane flies.
And I doubt that you, Cessna-boy, even get CLOSE to the g-forces involved in the kind of maneuvers done by military pilots, especially those trying to pull out of a dive.
And even if all of this WAS a tall order, that's exactly what fighter pilots are trained for; that's why so few people who apply are accepted, and why so few who are accepted make the grade in training.
Which is why, when they get into the air, they should be confident that someone has fucking sanity-checked the design of the safety features aboard the aircraft. Clearly, in this case, that was NOT done.
No, that is not what this means.
"Air bleed" is the method by which the OBOGS generates breathable air. It's called "bleed" because it "bleeds" off a small amount of air from the engine's compressor system. (This air can also be used for deicing flight surfaces, generating power, and other purposes).
An "air bleed failure" means that either no air is getting into the system, or a sensor failed and it thinks no air is getting into the system.
To summarize, this wasn't a failure where air was bleeding, this was a failure of the system that bleeds air from the engine for the pilot to breathe. That's important to understand.
Touch everywhere, even when inappropriate.
A series of engineers argue over who's fault it was.
Was it engineer A, who had to make the emergency system require 40kilos of pull to activate, due to flak that it might engage accidentally if the craft hits stiff turbulence or is kicked while the pilot is entering the cockpit?
Was it engineer B, who designed the oxygen recirculation system, and had to work within the physical space and weight restrictions imposed by engineers C and D, resulting in a suboptimal implementation?
Was it engineer C, who designed the superstructure of the figher's cockpit, for failing to fully appreciate the downstream requirements of his peers?
Was it engineer D, who designed the aesthetic and aerodynamic form of the fighter, imposing limitations on engineers A through C, and many others, for continuing the trend of smaller, faster, sleeker, and more compact designs?
Or was it engineer E, who oversaw ergonomic annd human interaction studies that led to the requirements statements fed to engineers A through D?
Was it the beaurocracies involved in construction, telling the engineers to use cheaper, more easily sourced materials so that the fighter comes out underbudget?
With all these parties in the room, bickering over who's fault it was, is it any wonder that the dead pilot, who can't stand up for himself, is the one that got blamed to save face?
Really. I work in aerospace. Many of the people in the engineering depts of major companies act like their shit doesn't stink, even when it obviously does. I make inspection blueprints, and when the degrees of a circular pattern exceed 360 degrees, or when point to point dimensions exceed total part length, and you inform them of the impossibility of these design specs, more often than not your time would be better spent talking to a brick wall.
It's like trying to have an informed discussion on computing with an ardent member of the cult of mac. All you will get back is snide remarks, or pretentious silence. You can quote rules of geometry until you are blue in the face. Quote directly from the gd&t manual for geometric tolerancing, or even play dumb and ask politely what their intentions were... result is almost always the same.
Don't you know, they have degrees, make big salaries, and are important. They never make mistakes. Just ask them.
I have been surprised a few times by polite aerospace engineers that own up to drafting errors, omissions, and flat out screwups before, and I am always cordial and polite with them. But for the most part, all I get back is silence, and derision.
(Just to clarify what I do: I make manufacturing drawings used for internal QA processes. Often times the customer supplied data is a digital nurbs representation of a part with some datum features called out, hole sizes listed and annotated, an some geometric tolerancing frames tacked on. My job is to take this data and in conjunction with the customer's tolerancing guidelines and practices documentation, create drawings that inspectors can use to validate the part was properly manufactured. This requires that they accurately convey the engineering intent of their geometry and datum choices. This is why I sometimes have to ask seemingly silly questions when they break the rules for gd&t frames, or define impossible (mathematically so) tolerances. You would probably be stunned how often I catch insane engineering mistakes because they pencilwhipped shit, and have to figure out the fit form and function myself, because they won't own up to it.)
The F22 program has cost around 66 billion dollars. That's about equivalent to a mission to Mars and two copies of the Superconducting Supercollider. That's equivalent to about 130 rovers of the same type as Opportunity and Spirit (ignoring the economies of scale that would substantially reduce the cost of having a lot of them). Etc. Etc. Instead we get unworking jet fighters that are supposed to be better than our previous jet fighters which are already estimated to be better than any other anyone else has in the world. Great priorities.
No. Read the report:
http://usaf.aib.law.af.mil/ExecSum2011/F-22A_AK_16%20Nov%2010.pdf
This wasn't a case of extraordinary circumstances. This was calm, high altitude flight where a critical (but understood) subsystem failed.
The pilot then became distracted by the system failure possible because of oxygen deprivation, or because the emergency air control was in an ergonomically challenging location. While distracted, he became inverted (240 degree roll during descent) and didn't attempt to correct until 3 seconds prior to impact.
The ergonomic issue may be a contributing cause. but a pilot *must* be able to continue instrument scan while dealing with an emergency. Just because you're air doesn't work doesn't mean you can't still crash while dealing with that.
It's sad, but more or less understood what happened.
Touch everywhere, even when inappropriate.
When Rolls Royce had to make their Merlin engine reliable enough fr long range bombing missions, they took every 10th engine off the production line and ran it constantly until it broke, took it apart and made whatever piece that failed stronger.
By the end of the war they had one of the most reliable piston engines the world has ever seen.
You've mixed things up, it makes no sense. I've read the report. Here's what happened:
1. The fire control system (FCS) detected a bleed air duct leak and has closed the isolation valves, cutting off engine bleed air from reaching the bleed air manifold (or duct). Bleed air is hot air from the compressor, used to power other systems. This triggers the "C BLEED HOT" caution.
2. Loss of bleed air made the following systems inoperational: environmental control system (ECS), forced air cooling for avionics et al (ACS), oxygen generator (OBOGS), inert gas generator (OBIGGS), cabin pressurization.
3. About 5 seconds after the bleed air was cut off, a new caution appeared: "OBOGS FAIL". This means the oxygen generator is out and you have to activate emergency oxygen generator on your seat - soon. That one is on your seat because it has to supply you with oxygen when you eject.
4. About 14 seconds later, a sensor picks up loss of oxygen pressure to the mask (from failed OBOGS).
That's all there's to it. Apparently the pilot never managed to activate emergency oxygen, and while fumbling with that he also bumped the control stick and rudder, causing the aircraft to fly a "random" trajectory. The cabin is cramped, and with extra cold weather gear it's nigh impossible to activate that emergency oxygen without bumping into things. That is a design issue, as well as the awkward way of activating that emergency oxygen system (you have to pull a ring from a hip level about 2 in. forward (away from you) with 40lb or more of force.
The report is here.
A successful API design takes a mixture of software design and pedagogy.
Sigh. Mistake upon mistake in those comments. The computer didn't detect any oxygen leaks. It detected a leak of hot air (bleed air) that is used to power various things, including oxygen generator (OBOGS). Since an uncontained leak of bleed air is likely to start a fire, the bleed air was automatically cut off by closing isolation valves at the engines. Thus it was no more powering the oxygen generator. The pilot fumbled for about 30s trying to activate emergency oxygen, eventually failing to do so, but while he was fumbling he bumped the control stick and rudder pedals, sending the aircraft on an uncontrolled inverted dive.
The bleed air is really hot -- between 1200F to 2000F (650C to 1000C). PHX (primary heat exchanger) then cools it down to 400F (200C).
There was some maintenance done in the previous months that required disconnecting the bleed air ducts, the accident investigators didn't think that anything went wrong there.
The bleed air leak was survivable, but somehow the pilot couldn't get emergency oxygen going, and lost situational awareness. When he tried to recover from the dive, it was too late.
A successful API design takes a mixture of software design and pedagogy.
The problem here with the Raptor is that they replaced the bottled oxygen system, used for decades in dozens of other aircraft, with a complex compressor system that's hooked to the engines. In this particular accident, the plane shut the compressor system down and hence the oxygen. You had a new dependency that, on the surface, seems nuts.
The resolution of the fault required the pilot to manually start the back up system. For whatever reason, the pilot was unable to do so.
Yeah, bleeding edge is bleeding edge but the real problem is that the military has bypassed the prototype system. You build a demonstrator on paper that requires several new technologies. You get the contract and of course once your are building the aircraft, THEN you find big issues. By then you're pretty much committed to either leaving the problem alone, doing some sort of kludge that makes the aircraft more expensive / less dependable and / or delaying the program.
This has been seen in pretty much every high tech military hardware purchase in the last two decades. And it keeps happening.
Faster! Faster! Faster would be better!
Aren't we usually in the middle of a war or two?
But you'd lose the entire war if you fielded Spitfires instead of F-22s.
A bit of googling gives 12,604 pounds as the unit cost for the Spitfire vs. $150 million for the F-22. Depending on which inflation and conversion calculators you believe, this might range between $300k and $950k per Spitfire today.
That gives you somewhere between 150 and 500 Spitfires per F-22.
Let's give the F-22 side enough resources to keep one plane on patrol at all times, and they can lose 10 F-22s before they lose the air war.
Then the Spitfire side can keep 150 planes in the air at all times, and they can lose 1500 planes before they lose the air war.
The two sides meet in the air. The Spitfires can't touch the F-22 because it's cruising nearly twice as high as the Spitfires can even fly. Furthermore, it can launch missiles to destroy the Spitfires from outside visual range. OTOH, that will only kill a dozen Spitfires, assuming perfect missile performance. At this point the F-22 has 480 rounds to shoot from its Vulcan cannon. Unfortunately, the F-22 is SO much faster than the Spitfires that it will tend to overtake them before it can do much aiming, so I'm going to say it's not a complete turkey shoot. Maybe another 2-3 dozen Spitfires go down. That leaves around 100 Spitfires left. They should be able to overwhelm the F-22 when it tries to land.
Unfortunately for the Spitfires, the F-22 can land outside of their range. Even if the F-22 airfields are in range, the Spitfires will have to split up into groups to cover them -- but that risks having an entire wing destroyed if they split into more than three groups.
That gets us to bombing. The Spitfires will take heavy losses, but they'll trash pretty much any airfield they attack. The F-22 can bomb the Spitfire airbases with impunity -- but its attacks will be like mosquito bites against the Spitfire's hundred airbases.
Taking all that into account, I'd say the Spitfires would lose a slow battle of attrition, unless ground forces could bring all the F-22 airbases into their range. Then the F-22s would be overwhelmed before they could kill enough Spitfires.
All this ignores SAM sites...and the missiles for those would be running cheaper than the unit cost of the Spitfires. That turns into another battle of attrition; I doubt one SAM site has more than a couple dozen missiles on hand at a time!
The report also says cabin pressure was lost. The incident happened at over 50,000 feet. At that altitude, air pressure is about 1/10th that at sea level. Even if you're breathing 100% oxygen, you're only getting about half the oxygen you would at sea level, about as much as you get at 15,000-20,000 feet. While that would've been enough to stave off unconsciousness, I'm skeptical just how useful the pilot's mental faculties would have been even if he turned on the emergency oxygen at that altitude.
From the plane's trajectory, it seems his first action upon comprehending the failure was to put the plane into a dive to get it into thicker, breathable air. Unfortunately it sounds like he lost consciousness during this maneuver, before he could turn on the emergency oxygen generator, and only regained consciousness a few seconds before impact.
Laminar flow gave it range via low drag and therefore reduced fuel consumption. It was unsatisfactory for its mission until the British got a hold of it and in fact, initially failed to perform up to anticipation. With the US made engine, it could only perform down low and high altitude performance was a requirement for long distance bomber escort. Without the British's contribution to the P51, it would have been little more than a footnote in history. Period.
if troops were treated with as much respect as 'the customer', they would get experimental shit rammed down their throats, and then told its their duty to die for the glory of some corporation.
dying in the f22 crash did not 'keep america safe'. it did not protect freedom. it did not have to happen.
this is the same fucked up attitude by the managers who think that somehow because of the two shuttle crew losses, it means space is 'inherently dangerous'. well if you ignore your engineers and only care about bullshit like politics and money, yeah, space is incredibly dangerous... its so dangerous that you can continue making exactly the same fuckups for years, without getting punished, even though your decisions cost the lives of people.
if someone is willing to die for their country, it takes a really low bellied sack of shit to believe to take that willingness for granted, and chalk up their death to inevitable accidents, which, upon further investigation, typically prove to have been completely avoidable, if it wasnt for some fucked up shitbag pencil pushing ass lick managment douchebag who will never get any punishment or reprimand for his negligence and stupidity.
Computers shouldn't be running gas throttles or braking systems in cars either. But it seems "cool" to be cutting edge. Even tho plain old mechanical systems are cheaper, safer and easier to use. Computer controlled isn't always better. And in some cases it's down right stupid.
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