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causes of F-22 oxygen problem have been found

This is a discussion on causes of F-22 oxygen problem have been found within the Air Force & Aviation forum, part of the Global Defense & Military category; As a new guy I can't post links. Please go to see the full video explanation on youtube please: search ...


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Old June 2nd, 2012   #1
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causes of F-22 oxygen problem have been found

As a new guy I can't post links. Please go to see the full video explanation on youtube please:
search this title: causes of F-22 oxygen problem have been found

Since the crash of F-22 in Alaska in November 2010. The mysterious oxygen supply problem is so far still a mystery. No one know what the real causes is. It takes the Lockheed, Honeywell, and USAF 2 years to not identify the real causes. And now it took me 3 minutes to do the job.

About 20 days ago. Two F-22 pilots talked on 60 minutes about this problem. After I seen the video. Instantly I found the real causes of the F-22ís oxygen problem and made some posts on my Google plus on May 8, 2012.

Now Iet me explain to you in detail about my theory.
letís first take a look of these facts:

1.
The same sort of OBOGS made by Honeywell on other platforms performs ok. These platform according to their company catalog Including : Eurofighter ; F-35 ; BAE HAW ; BAE/SAAB gripen; F-18; PILATUS PC-21; Nimrod MRA MK4 ; Harrier; F-14; B-1B; B-2B.

So why other aircraft have no oxygen problem and the F-22 does?

The answer is clear: They are all not designed to fly at high altitude. They canít perform violent maneuver at high altitude like F-22 dose. Especially the high AOA, low speed and post stall maneuver.

At high altitude. The air is so thin. Without sufficient air-speed to draw more air into the engine the engine is simply getting under charged. And the bleed air from the engine compressor goes for the OBOGS is under-pressurized. This will cause the OBOGS to malfunction and do not producing sufficient oxygen. And will also possibly cause the cabin pressure to drop. Because the bleed air is also be used to pressurize the cabin. Unlike civil air-liner. Fighter jets cabin pressurization is not maintained constantópressure differential mode; At high altitude in the thin air. Cabin pressure drops and oxygen in-sufficient together with the increase oxygen demand of pilot due to violent aerobatics may works together to cause hypoxia that will endanger the flight.

The OBOGS system is a physical gas separation device, It use the selective absorption property of molecular sieve to separate oxygen and nitrogen in the air. Producing enriched oxygen for the pilot to breath.

The technology is called pressure swing adsorption (PSA). It relies on the pressure changes of air to let the zeolites absorbing specific gas then release to produce enriched oxygen and/or nitrogen.

to make the OBOGS work and deliver required oxygen enriched air. The input air must have enough pressure to generate a big enough pressure swing. At low altitude this is OK no matter how the airplane maneuvers. But the F-22 is designed to fly at high altitude where air is very thin. Normally when the plane flying fast. With the air ramming effect the engine will produce bleed air with enough pressure.

But when the plane fly at low speed at that altitude. especially when doing post stall maneuvers. Without the air ramming effect the engine is simply getting under-charged.

Now you see. High altitude slow flight is the single most important contributing factor of the mysterious oxygen problem of the F-22 raptor.


2.
Not every F-22 flight will cause the pilot to suffer from hypoxia. the incidents happens occasionally, unpredictable, and often time the pilot doesnít even notice it.
Reason for this?
Simple. Not every flight they will perform low speed high altitude maneuver.

3.
the 2 pilots talked on 60 minutes says most of them is having the so called raptor cough and is spitting black sputum with charcoal dust.
This is because the frequent high altitude flight doing low speed violent maneuver. They been constantly suffer from lack of oxygen and exposure to low cabin pressure. Even worse is these violent maneuver make the pilot to consume much much more oxygen. The charcoal problem is a stupid engineering fault. Even idiots know how to handle the filterís charcoal problem. Just add some fiber based filter. Like PP cotton and non-woven fabric


This week some report says there also been found some problem of possible cooling liquid infiltration and BRAG valve malfunction. Since I know only limited information about the inside of the OBOGS of F-22 I am not sure whether this could also be the contributing factors.

To identify the real causes and prove my theory. Please do the following thing:

1. Equip the F-22 with oxygen tanks or chemical oxygen generator or other sort of oxygen generating systems that do not depend on bleed air.
2. Install pressure sensor in the cabin, and gas percentage reading sensor in the mask and the cabin. All these data shall be recorded every single seconds.
3. get the F-22 back into the air, Doing slow flight and post stall maneuver at high altitude. If my theory is right. The sensor records will tell the entire story.

4. after prove my theory is right. Do the following thing
A: Add another stage of electric compressor the provide more air pressure for the OBOGS.
B: An oxygen tank is needed as backup oxygen supply in case the OBOGS fail.


I am 100% sure about my theory. And hope it will help in someway.
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Old June 3rd, 2012   #2
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Originally Posted by JameLi1986 View Post
As a new guy I can't post links. Please go to see the full video explanation on youtube please:
search this title: causes of F-22 oxygen problem have been found

Since the crash of F-22 in Alaska in November 2010. The mysterious oxygen supply problem is so far still a mystery. No one know what the real causes is. It takes the Lockheed, Honeywell, and USAF 2 years to not identify the real causes. And now it took me 3 minutes to do the job.

About 20 days ago. Two F-22 pilots talked on 60 minutes about this problem. After I seen the video. Instantly I found the real causes of the F-22ís oxygen problem and made some posts on my Google plus on May 8, 2012.

Now Iet me explain to you in detail about my theory.
letís first take a look of these facts:

1.
The same sort of OBOGS made by Honeywell on other platforms performs ok. These platform according to their company catalog Including : Eurofighter ; F-35 ; BAE HAW ; BAE/SAAB gripen; F-18; PILATUS PC-21; Nimrod MRA MK4 ; Harrier; F-14; B-1B; B-2B.

So why other aircraft have no oxygen problem and the F-22 does?

The answer is clear: They are all not designed to fly at high altitude. They canít perform violent maneuver at high altitude like F-22 dose. Especially the high AOA, low speed and post stall maneuver.

At high altitude. The air is so thin. Without sufficient air-speed to draw more air into the engine the engine is simply getting under charged. And the bleed air from the engine compressor goes for the OBOGS is under-pressurized. This will cause the OBOGS to malfunction and do not producing sufficient oxygen. And will also possibly cause the cabin pressure to drop. Because the bleed air is also be used to pressurize the cabin. Unlike civil air-liner. Fighter jets cabin pressurization is not maintained constantópressure differential mode; At high altitude in the thin air. Cabin pressure drops and oxygen in-sufficient together with the increase oxygen demand of pilot due to violent aerobatics may works together to cause hypoxia that will endanger the flight.

The OBOGS system is a physical gas separation device, It use the selective absorption property of molecular sieve to separate oxygen and nitrogen in the air. Producing enriched oxygen for the pilot to breath.

The technology is called pressure swing adsorption (PSA). It relies on the pressure changes of air to let the zeolites absorbing specific gas then release to produce enriched oxygen and/or nitrogen.

to make the OBOGS work and deliver required oxygen enriched air. The input air must have enough pressure to generate a big enough pressure swing. At low altitude this is OK no matter how the airplane maneuvers. But the F-22 is designed to fly at high altitude where air is very thin. Normally when the plane flying fast. With the air ramming effect the engine will produce bleed air with enough pressure.

But when the plane fly at low speed at that altitude. especially when doing post stall maneuvers. Without the air ramming effect the engine is simply getting under-charged.

Now you see. High altitude slow flight is the single most important contributing factor of the mysterious oxygen problem of the F-22 raptor.


2.
Not every F-22 flight will cause the pilot to suffer from hypoxia. the incidents happens occasionally, unpredictable, and often time the pilot doesnít even notice it.
Reason for this?
Simple. Not every flight they will perform low speed high altitude maneuver.

3.
the 2 pilots talked on 60 minutes says most of them is having the so called raptor cough and is spitting black sputum with charcoal dust.
This is because the frequent high altitude flight doing low speed violent maneuver. They been constantly suffer from lack of oxygen and exposure to low cabin pressure. Even worse is these violent maneuver make the pilot to consume much much more oxygen. The charcoal problem is a stupid engineering fault. Even idiots know how to handle the filterís charcoal problem. Just add some fiber based filter. Like PP cotton and non-woven fabric


This week some report says there also been found some problem of possible cooling liquid infiltration and BRAG valve malfunction. Since I know only limited information about the inside of the OBOGS of F-22 I am not sure whether this could also be the contributing factors.

To identify the real causes and prove my theory. Please do the following thing:

1. Equip the F-22 with oxygen tanks or chemical oxygen generator or other sort of oxygen generating systems that do not depend on bleed air.
2. Install pressure sensor in the cabin, and gas percentage reading sensor in the mask and the cabin. All these data shall be recorded every single seconds.
3. get the F-22 back into the air, Doing slow flight and post stall maneuver at high altitude. If my theory is right. The sensor records will tell the entire story.

4. after prove my theory is right. Do the following thing
A: Add another stage of electric compressor the provide more air pressure for the OBOGS.
B: An oxygen tank is needed as backup oxygen supply in case the OBOGS fail.


I am 100% sure about my theory. And hope it will help in someway.
This theory is fantastically exciting and really very good for the USAF! One person beats the entire engineering staff of Lockheed Martin to solve the oxygen problem on the F22.
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Old June 3rd, 2012   #3
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I would like to enquire about your theory

1 - How would you explain the contaminants (Propane, Anti-Freeze, CO - which on it's own would directly cause hypoxia no matter how well OBOGS works, + burned synthetic oil) in the affected pilots bloodstream?

F-22 Grounding: Propane, Anti-Freeze, and Other Toxins Found in Pilots’ Blood | Aviation & Air Force News at DefenceTalk

2 - If the fault is directly caused by a faulty OBOGS system, how come issues haven't been noticed until 2010ish and not sooner? After all, one would assume that such aircraft would have carried out the maneuvers before the 4-odd years since it became operational?
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Old June 3rd, 2012   #4
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There's also another problem with your theory. After Capt. Haney's crash, all F-22 flights were restricted below 25,000 ft. However, there were still plenty more incidents (including the pilot who hit a few trees on approach for his landing), after this flight level restriction.
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Old June 3rd, 2012   #5
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"One person beats the entire engineering staff of Lockheed Martin to solve the oxygen problem on the F22."

My first post was meant as sarcasm or questioning the theory that the oxygen problem was actually solved. There must be thousands of Lockheed Martin engineers working and trying to identify the root cause of the problem? Just don't see one person can solve this problem as he theorized?
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Old June 4th, 2012   #6
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The toxins is from the leaking cooling unit. These anti-freezer is used by the cooler. Propane,CO, hydrocarbons are from the core of the compressor where air is being drawn out as bleed air. The same problem is found on civil jets also.

What about the time before the 2010 crash. I can't explain it. My initial thinking is like this: The incidents is rare, Before they deploy 180+ F-22 into service. The incidents is even more rare.

The 2010 crash acording to new report they say the bleed air is leaking and the system is shuted down. But the pilot have failed to activated the backup oxygen supply. This indicate to me one thing
:
They have no sensor to detect the OBOGS output pressure. And thus make me believe even more on my theory. That frequent low oxygen output of the OBOGS due to high altitude + low speed is the root causes of the F-22's problem.
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Old June 4th, 2012   #7
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-------
25000 feet is still a pretty high altitude. You can't let F-15 to fly at that altitude at 250mph or less.

But F-22 can. And it can roll over, flip, doing post stall maneuvers.
The pilot hit a tree ? when? I have very limited information about these detail. All my information is from publicly available resources.
Must be it's wing cut a tree's tip off I guess. For a 30 ton F-22. Such kind impact may be ignored. You know some times they hit bird but they didn't notice until they land.
The 60 minutes days. The pilot suffer from dizziness,spinning room feelings one day after they flight. This I guess is a compound result of frequent exposure to low cabin pressure, low oxygen and toxic contaminants from the bleed air.
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Old June 6th, 2012   #8
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I been read from news that the pressure suit they wear might be the problem . And neurotech on F-16 forum says:
The F/A-18 can show an OBOGS warning at high altitude if there is low outflow pressure from a leak or something. I'm not certain if the F-22 has a OBOGS low outflow pressure warning or not.
---
If this is true. Then I believe my theory is wrong. The OBOGS of F/A-18 is also produced by honeywell. So they must also have such a warning mechanism.
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Old June 6th, 2012   #9
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An interesting theory.

There has been alot of discussion about the systems involved but very little about aeromed, physiology and so forth. Without knowing the pressures involved it's difficult to discuss the effects of high hypoxia associated with low pressure differentials between the oxygen and the bodies tissues. At 40,000 or so you can't pressurize oxygen enough to create the required pressure differential between it and the body's tissues to allow oxygen tranference which occurse via Henry's Law. Tecnically you can with an overpressurized oxgen mask but diaphram fatique (in the human body) occurs rather quickly and it's use and practicallity are severely limited.

I can not source it now but weeks ago there was some news that some maintainers have exhibited symptoms of hypoxia. The cause may be linked to something other than pressure/quantity of oxygen. Carbon monoxide for example, prevents oxygen molecules from bonding with hemoglobin causing hypoxia. Therefore I don't think the problem has been completely assigned to OBOGS ability to supply the necessary quantity and pressure of O2.
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Old June 6th, 2012   #10
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I can not source it now but weeks ago there was some news that some maintainers have exhibited symptoms of hypoxia. The cause may be linked to something other than pressure/quantity of oxygen. Carbon monoxide for example, prevents oxygen molecules from bonding with hemoglobin causing hypoxia. Therefore I don't think the problem has been completely assigned to OBOGS ability to supply the necessary quantity and pressure of O2.
Agreed, which is why I still believe that the fault is much more than a dodgy OBOGS unit acting up at high altitude during maneuvers.

One theory was that in places like Alaska, where the engines are started inside hangers, that maybe the exhaust fumes are being sucked back in. But that was disregarded due to the faults occuring when that hasn't happened.

I'm more drawn to the idea that an internal component has worn faster than predicted causing some sort of fume bleed problems, but still you'd have thought that would be simple-ish to solve.
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The experts seem to be zeroing in on the anti-G suit as a major contributor to the woes experienced by Raptor drivers. If so, the OBOGSissue ay actually have been a red herring and perhaps simply suiting up inthe G-suit being developed for F-35 pilots could be the answer. It still doesn't address the issue of physiological symptoms reportedly being claimed by some ground crew but then again, that could be being caused by something cokpletely different. Anyway, progress seems to be being made.

F-22′s anti-g suit could be source of oxygen woes | idrw.org
F-22′s anti-g suit could be source of oxygen woes

Published June 6, 2012 | By admin

SOURCE: FLIGHT GLOBAL

The Combat Edge upper pressure-garment worn by US Air Force pilots flying the Lockheed Martin F-22 Raptor might be the cause of the fifth-generation fighterís oxygen maladies, sources say.
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Old June 9th, 2012   #12
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The experts seem to be zeroing in on the anti-G suit as a major contributor to the woes experienced by Raptor drivers. If so, the OBOGSissue ay actually have been a red herring and perhaps simply suiting up inthe G-suit being developed for F-35 pilots could be the answer. It still doesn't address the issue of physiological symptoms reportedly being claimed by some ground crew but then again, that could be being caused by something cokpletely different. Anyway, progress seems to be being made.

F-22′s anti-g suit could be source of oxygen woes | idrw.org
F-22′s anti-g suit could be source of oxygen woes

Published June 6, 2012 | By admin

SOURCE: FLIGHT GLOBAL

The Combat Edge upper pressure-garment worn by US Air Force pilots flying the Lockheed Martin F-22 Raptor might be the cause of the fifth-generation fighterís oxygen maladies, sources say.
Thanks for that post colay, that is starting to sound much more plausible, the Raptor is capable of sustaining 9.5 gs, and that will definetly put you in a condition of a lot of physical fatique in a hurry, and I had read a little about the U-2 pilots, which I had never heard of before. As another poster had noted, many nations do not fly in a full suit, but only pants, the additional capabilities of the Raptor preclude that. To the OP, thanks for putting your theory out there at least, I think you will concur that the source colay posted is likely on to something, I do hope that they nail this down shortly. Cheers Brat and I learn something once again.
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Old June 10th, 2012   #13
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Thanks for that post colay, that is starting to sound much more plausible, the Raptor is capable of sustaining 9.5 gs, and that will definetly put you in a condition of a lot of physical fatique in a hurry, and I had read a little about the U-2 pilots, which I had never heard of before. As another poster had noted, many nations do not fly in a full suit, but only pants, the additional capabilities of the Raptor preclude that. To the OP, thanks for putting your theory out there at least, I think you will concur that the source colay posted is likely on to something, I do hope that they nail this down shortly. Cheers Brat and I learn something once again.
Hmm i do wonder i have heard the ground crews have also suffered problems. So in that case maybe its something getting into the exaust or some chemical reaction in the skin coatings or some such.
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Old June 10th, 2012   #14
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Hmm i do wonder i have heard the ground crews have also suffered problems. So in that case maybe its something getting into the exaust or some chemical reaction in the skin coatings or some such.
Hey chief, I just replyed on another thread to one of your posts. I'm in Chitown tonight, there are lots of possibilities for ground crewmen to be exposed to lots of goodies on the Raptor, I would wonder if it were crewchiefs or other operational personnel, that does seem to be the implication. If that is the case, I can recall giving a cart start to one of my friends who flew a Mitsubishi turbo prop, and the GPU plug was on the port side aft of the port engine. I can recall wearing my mickey mouse ears and looking up the exhaust outlet as the Mitsi spooled up, it would often belch a little flame in my direction because of a faulty fuel controler, when he put the fire to it, and even with the mickey mouse ears, it was loud. The JP smelled wonderfull to me after it was burnt, so I really didn't mind the exposure to the hot gases, but they dissapated quickly as I was outdoors. Once he was up and running on both engines, I pulled the plug and buttoned her back up. Now if its maintainence personnel on the stealth coatings, I would imagine that those fumes are quite noxious as well.
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Old June 10th, 2012   #15
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Hey chief, I just replyed on another thread to one of your posts. I'm in Chitown tonight, there are lots of possibilities for ground crewmen to be exposed to lots of goodies on the Raptor, I would wonder if it were crewchiefs or other operational personnel, that does seem to be the implication. If that is the case, I can recall giving a cart start to one of my friends who flew a Mitsubishi turbo prop, and the GPU plug was on the port side aft of the port engine. I can recall wearing my mickey mouse ears and looking up the exhaust outlet as the Mitsi spooled up, it would often belch a little flame in my direction because of a faulty fuel controler, when he put the fire to it, and even with the mickey mouse ears, it was loud. The JP smelled wonderfull to me after it was burnt, so I really didn't mind the exposure to the hot gases, but they dissapated quickly as I was outdoors. Once he was up and running on both engines, I pulled the plug and buttoned her back up. Now if its maintainence personnel on the stealth coatings, I would imagine that those fumes are quite noxious as well.
Thats what im wondering if its fumes getting into the oxygen system and just around the plane itself. Maybe something they didnt notice that happens after a few hours at high speed or slowly starts releasing over time.
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