Hypoxic Training

By LEE FERRAN
Oct. 26, 2011

The full force of America’s most sophisticated and expensive fighter jets are flying again today even though the Air Force remains stumped as to what could be causing some pilots to suffer apparent oxygen deprivation mid-flight.

Two U.S. bases called for a “pause” in training and homeland defense operations after a pilot at Virginia’s Joint Base Langley-Eustis reported experiencing hypoxia-like symptoms during a flight last week, but after studying the incident, both bases green-lit resumption of missions Tuesday, the Air Force said.

The full fleet of the $143 million-a-pop F-22 Raptors — which have yet to see combat — was grounded for more than four months earlier this year while the Air Force investigated the cause of 12 other separate, similar incidents since 2008. Nearly six months since the original grounding, the Air Force admits it still does not know why some of its pilots, on relatively rare occasions, showed different “hypoxia-like symptoms”.

“It’s not just that ‘the problem’ wasn’t identified — there was no conclusive cause or group of causes,” Air Force spokesperson Lt. Col. John Haynes told ABC News Monday. “In different situations, there were different types of symptoms at different times. There was no common thread they [investigators] found to link all these together.”

Hypoxia occurs when the brain does not receive enough oxygen and can cause dizziness, confusion and “poor judgment”.
PHOTO With the United Nations authorization for an internationally monitored no-fly zone over Libya the United States began with the deployment of F-22 stealth fighters over the region.
Yoshikazu Tsuno/AFP/Getty Images
A US Air Force’s new stealth fighter F-22A… View Full Caption
A US Air Force’s new stealth fighter F-22A Raptor lands at Kadena US Air Base in Kadena in this Feb. 18, 2007 file photo. With the United Nations authorization for an internationally monitored no-fly zone over Libya the United States began with the deployment of F-22 stealth fighters over the region. Close

Haynes said that the Air Force had been “cautiously moving forward” and had successfully launched 1,300 missions since the original grounding was lifted before the incident at Langley. Though the Air Force has 181 F-22s stationed at a handful of bases around the U.S. and abroad, the “pause” over the weekend only affected Langley and Alaska’s Joint Base Elmendorf-Richardson. Elmendorf-Richardson has not experienced an incident recently, but it is the home base of the late Capt. Jeffrey Haney, who was killed in an F-22 crash during a nighttime training mission in November 2010. An investigation into that crash is ongoing, the Air Force said, but Air Force Chief of Staff Gen. Norton Schwartz told reporters last month the oxygen system was definitely not the cause of the crash, despite news reports to the contrary.

Along with the F-35 fighter, which is slightly less expensive per plane, the F-22 marks America’s foray fifth-generation stealth fighter jets that the Air Force said can dominate the air space anywhere in the world — even if they’ve never had to prove it.

READ: The $77 Billion Fighter Jets That Have Never Gone to War

Not a single one of the Raptors — which cost U.S. government $77.4 billion for a total of 187 planes from developer Lockheed Martin — has been used in combat operations and isn’t expected to “any time soon,” an Air Force official told ABC News last month.

The Pentagon initially ordered more than 600 of the fifth-generation fighters, but Congress stopped at funding 187 in 2009 under a hail of criticism over the fact that the planes are designed to take on other rival high-tech fighter jets instead of the third-world militaries and insurgents the U.S. currently faces.

Only recently have rival major powers — including Russia and China — unveiled their prototypes for what are believed to be their own stealth fighters, designed to take on the F-22.

Haynes said that since the original grounding, base commanders everywhere are keeping a vigilant lookout for problems with Raptor pilots in the air.

“Everybody knows, everybody’s watching,” Haynes said.

By Stephen Trimble

Lockheed Martin F-22A Raptors have been cleared to fly for the first time in four months, but the oxygen problem that grounded them remains a mystery to the US Air Force.

It will be two months before F-22A pilots regain full operational capability of the fighters after the four-month hiatus, Gen Norton Schwartz, USAF chief of staff, said on 20 September.

The USAF’s wide-ranging safety investigation, which was prompted by the incidents that caused the grounding, could take even longer.

Sixteen flight tests were filed to identify the source of possible contamination of the F-22A’s oxygen supply, which had caused 12 pilots to report hypoxia-like symptoms since April 2008.

However, the USAF has since determined that a fatal F-22 crash in November 2010, in Alaska, was not caused by a fault in the aircraft’s oxygen system, Schwartz said. The actual cause of the crash has not been released.

“We do not have a smoking gun here,” Schwartz said.

Pilots will wear “certain protective equipment” on F-22 missions, and receive new training on emergency procedures, he added.

The USAF also will continue to collect data on oxygen quality during daily flight operations.

A broader safety review of the onboard oxygen generation systems (OBOGS) on USAF combat aircraft also is ongoing.

The technology replaced liquid oxygen canisters in modern military aircraft in the 1970s.

The USAF became concerned about OBOGS on the F-22A after last year’s fatal crash. On 3 May, US Air Combat Command put the Raptor fleet on a voluntary safety stand-down, as the investigation progressed.

As that stand-down now enters it’s 4th month, there are concerns the F-22 pilots are losing their training edge. The Air Force’s entire fleet of F-22 raptor has been grounded since May 3rd.

Blood tests found toxins in pilots blood, but the Air Force still doesn’t know what’s wrong with the system.

The Air Force stopped flying Raptors after pilots started complaining about hypoxia and decompression sickness, both caused by a lack of oxygen.

In the meantime, pilots are in danger of losing their currency in the F-22. Pilots who don’t fly in 210 days, have to retake the entire training course. The Air Force is working on a requalification program.

Those who were learning to fly the F-22 as their first jet are getting classroom and simulator time.

Until then, pilots who were supposed to be transitioning to the Raptor have been ordered to return to their home bases.

As the F-22 grounding enters its fourth month, pilots are losing proficiency on the fifth generation stealth fighter, as they are unable to meet the required number of flight hours each month.

The Air Force Times reports Air Force Vice Chief General Philip Breedlove as saying that pilots, despite ongoing simulator training, can’t maintain their currency in the F-22.

Raptor pilots are required to fly a certain number of sorties every month to stay current, but because the Raptors are grounded, those who were destined to begin flying the F-22 have been told to return to their home bases. Pilots just learning to fly the Raptor are limited to simulator flights, but there are only two F-22 simulator complexes, one at Langley Air Force Base and another Tyndall AFB. Even the elite pilots at the US Air Force Weapons School have been told to return to their home bases during the grounding.

If a pilot has not flown in seven months, they will have to start the training procedure over again. “Certainly, as we restart training we’ll have to regain those currencies just like in any other grounding of any other aircraft,” Breedlove said.

Each F-22 wing is developing a shortened requalification program to accommodate the grounded pilots, the Air Force Times story said.

“Once the designated number of sorties have been flown to achieve re-qualification, all pilots must fly their regular number of monthly sorties and commanders will then declare when their unit is sufficiently trained and ready for various taskings,” said Air Combat Command (ACC) spokesperson Captain Jennifer Ferrau.

Entire fleet of 165 F-22 Raptors, are grounded. 187 are on order, following a stand down from May 3 after reports of “oxygen system malfunctions” that could have caused pilot hypoxia (oxygen starvation).

There have been nine suspected cases of hypoxia during F-22 operations since mid-2008, and recently there have been 14 recorded OBOGS incidents up until now.

The F-22 Raptor, the Air Force’s most advanced weapons system, is the only fighter capable of “simultaneously conducting air-to-air and air-to-ground combat missions with near impunity,” maker Lockheed Martin says on its website.

Now, if they could only get off the ground.

The Hawaii Air National Guard and active-duty Air Force showcased the stealth aircraft Friday at Joint Base Pearl Harbor-Hickam, where a groundbreaking was held for a $37.1 million maintenance hangar and squadron operations facility for the F-22s.

The Hawaii Air Guard has seven Raptors here, two on the mainland awaiting maintenance and 11 others that were supposed to fly in by the end of the year, officials said.

But an investigation into “hypoxia-like” symptoms — meaning not getting enough oxygen — experienced by some pilots elsewhere has left all Raptors in the Air Force inventory on stand-down since early May with no end to the grounding in sight.

Oxygen-generation systems continue to be looked at, the Air Force’s Pentagon office said.

About 200 people, including Gov. Neil Abercrombie, attended the groundbreaking for the new 77,500-square-foot hangar and operations facility, which the Guard said will allow it to demolish nine older buildings. The new hangar will be able to house six F-22s.

Honolulu-based Watts Constructors will be involved in building the new facility.

President Denny Watts said “jobs of this size make so much more impact” on work for prime contractors, subcontractors and vendors. He expects 50 and 60 workers to be on the job site.

F-22 improvement projects at Hickam totaling $156 million are expected to be completed through the next four to five years, officials said.

The Hawaii Air National Guard had been flying the Raptor since last summer in partnership with the active-duty Air Force and was steadily building up the squadron of aircraft.

Hawaii Adjutant General Maj. Gen. Darryll D.M. Wong acknowledged after the groundbreaking that there has been some pilot frustration with the inability to fly the stealth jets.

“I think for the pilots, it’s kind of like you just learned to drive a really fast car, and then they took the keys away from you,” Wong said.

Wong, head of 5,500 Hawaii National Guard Army and Air Guard members, said he is not sure what the stand-down will do to the arrival schedule of the remaining 13 Raptors.

The grounding also has ramifications for pilot training and readiness. Mainland training schools have been suspended, he said.

“The Air Force, along with figuring out how to fix this airplane, will also have a plan forward on how to take the pilots that have been grounded and how to systematically get them back flying again,” Wong said.

Some bases have F-22 simulators. Hickam doesn’t have one yet, he said.

“So whether these people go back to the mainland somewhere and get into the simulators and then get back into the airplane here is still yet to be determined,” Wong said.

Maintenance personnel, on the other hand, have been able to “really get into the airplane and learn it,” Wong said.

The Air Force said Thursday it is continuing to review all of its aircraft equipped with oxygen-generation systems, but said the F-22 is the only grounded airplane.

An Alaska F-22 pilot died in November when he lost control of his jet during training. The jet crashed about 100 miles north of Anchorage.

A team led by retired Air Force Gen. Gregory Martin will examine systems identified in reported incidents, including pressurization systems and mask and cockpit oxygen levels, the service said.

Air Force Times, quoting unnamed sources, said carbon monoxide might have entered the cockpit of jets whose engines were started inside hangars at Elmendorf Air Force Base in Alaska, where most of the hypoxia incidents have occurred.

F-22 Oxygen Problems Possibly Linked to JBER Procedures

By Chris Klint KTUU.com
read full story:

http://www.ktuu.com/news/ktuu-f22-oxygen-problems-possibly-linked-to-jber-procedures-20110721,0,1824401.story

July 21, 2011
ANCHORAGE, Alaska—
Air Force investigators are looking into whether engine startup procedures for F-22 Raptor jets at Joint Base Elmendorf-Richardson could be responsible for reports of hypoxia related to the stealth fighters’ oxygen-supply system.

According to the Air Force Times, most of the hypoxia incidents have occurred at JBER, where F-22s are often started up inside hangars due to harsh weather outside. Investigators believe carbon monoxide generated by the Raptors’ own jet engines could be getting ingested back into the engines’ bleed air intakes. Those intakes supply the on-board oxygen generation system, or OBOGS, which provides oxygen to the pilot.

JBER officials had no comment on the issue Thursday.

The Air Force barred the 158-aircraft Raptor fleet from flying above 25,000 feet in January after receiving nine reports of symptoms similar to hypoxia, a form of oxygen deprivation. The fleet later received a May stand-down order to investigate OBOGS concerns, following five more reports of similar symptoms within a week.

Air Force Capt. Jeffrey Haney, 31, was killed on impact Nov. 16 when his 525th Fighter Squadron F-22 lost contact with air traffic control and a partner aircraft, then crashed during a training exercise about 100 miles north of Anchorage.

The Air Force said its investigation of the November crash was incomplete, and it had no conclusive evidence to connect Haney’s death to the OBOGS issue.

Officials say the F-22’s bleed air intake positions are fairly common for jet aircraft, and that no immediate fix is in sight. Aviation-safety expert Hans Weber told the Times, however, that simple solutions might include starting Raptors’ engines outside hangars or delaying startup of the oxygen system until leaving the hangar.

Failing that, Weber said, tackling the problem might require adding CO scrubbers to the plane’s oxygen system.

The Navy experienced similar problems with its F/A-18 Hornet fighters during carrier operations from 2002 to 2009, with 64 hypoxia cases reported — including two involving pilot deaths. An investigation suggested that the problem was caused by carbon monoxide entering the oxygen system while pilots idled behind other aircraft waiting to take off, and the Hornets were modified to fix the problem.

No similar incidents have been reported in F/A-18s since the fix, according to the Navy.

[204] ANOXIA 1939-1945: ORIGINS OF THE HIGH ALTITUDE TRAINING PROGRAMS IN THE USAAF AND USN IN WORLD WAR II

J.B. DEAN

Molecular Pharmacology A Physiology, Hyperbaric Biomedical . Research Laboratory, University of South Florida, Tampa, FL

INTRODUCTION: Sir Frederick Banting, co-discover of insulin and the head of aeromedical research in the RCAF, predicted (1940) that the first nations to place the heaviest armaments above 40,000ft would win WWII. Banting’s prediction inspired much of the Allies’ physiological training and research, but routine aerial warfare above 40,000ft was never realized during WWII. The research and practices established, however, laid the foundation for aerospace medicine in the post-war era. Altitude chambers were procured for indoctrination ”flights” to 28,000, 35,000 & 40,000ft to educate airmen as to the dangers of ”anoxia” and ”fliers’ bends”, and how to use their O2 equipment under strenuous conditions. Targeted altitudes were selected based on the known effects of anoxia on pilot performance and the altitudes at which the risk for ”bends” increased. 2069 chamber ”flights” to >35,000ft were made between 7/1/41- 6/30/42 at Wright Field and 70% of these were to 40,000ft with a maximum altitude of 44,800ft (15-44min) using the ”new” demand O2 mask. Recall that the pressurized demand O2 mask and pressurized B-29 aircraft were introduced, respectively, in 1943 and 1944. The goal in 1941 was ”…to convince the young pilot or crew member that his mental functioning falls below par when he goes to 15,000ft without O2, that he is likely to faint if he goes above 20,000ft without O2 and that when he goes above 40,000ft, even with pure O2, he is in a precarious state” (D.B. Dill, 2 Dec ’41). Early research at Wright Field (Jan-May ’42) indicated that the time of useful consciousness following explosive decompression from 10,000 to 25,000ft (70.2s) decreased with increasing altitude: 30,000ft (43.5s), 35,000ft (25s), and 40,000ft (14s). Aviators also were taught the effects of cold and exercise on O2 consumption at altitude; i.e., O2 equipment became limited at 30,000ft when intense work was performed. Altitude chambers also were used to try and classify airmen as to their risk for bends, the benefits of 02 prebreathing to reduce risk of bends, how to ventilate the middle ear and sinuses, the debilitating effects of expanding intestinal gas and the importance of diet, and to diagnose problems of an ”organic” nature (hyperventilation/ anxiety).

Learning Objectives:

1 To revisit and identify the rationale for using hypobaric chambers to produce altitudes ranging from 28,000 to 40,000 feet in WWII for teaching pilots and aircrews the physiological effects of high altitude and how to use their O2 equipment.

[205] U.S. NAVY FA-18 IN-FLIGHT HYPOXIA EPISODES: RATES AND CAUSES

N.A. DAVENPORT AND D. DELOREY

Norfolk, VA

INTRODUCTION: In-flight hypoxia has been noted for some time as a significant physiological threat to USN F/A-18 aircrew; however no recent study has been conducted to determine an associated in-flight hypoxia rate or identify the causes of in-flight hypoxia. Traditionally, F/A-18 aircrew have been trained to recognize the signs and symptoms of hypoxia using hypobaric chamber training at simulated altitudes of 25,000 ft or more. However, in an effort to provide greater realism of training (mask on), and eliminate the risk of decompression illness, the USN has recently replaced the hypobaric chamber with the reduced oxygen breathing device (ROBD) for all F/A-18 aircrew hypoxia training. ROBD training was fully implemented for Navy tactical aviation in 2006. METHODS: All reported episodes of hypoxia submitted to the Naval Safety Center for the period FY02-FY09 were analyzed to establish an in-flight hypoxia rate per 100,000 flight hours, and determine the causes of in-flight hypoxia. RESULTS: During the period studied, F/A-18 aircrew reported 64 episodes of in-flight hypoxia (approximately 8 episodes/year) with two of the 64 (3.1%) episodes resulting in Class A Flight Mishaps (with two associated fatalities). The majority (77%) of hypoxia episodes occurred in single seat F/A-18 aircraft, with two-seat F/A-18 aircraft accounting for the remaining 24% of the hypoxia episodes. The overall hypoxia rate for the F/A-18 is 2.7 episodes per 100,000 flight hours, with the single seat F/A-18 having a rate of 3.2 episodes per 100,000 flight hours and the two-seat F/A-18 exhibiting a rate of 1.7 episodes per 100,000 flight hours. DISCUSSION: The most common citied cause of in-flight hypoxia in the F/A-18 was the failure of the OBOGs system (29%), while the most frequently noted hypoxia symptom by the aircrew was tingling in the extremities (43%). Other symptoms of hypoxia included: lightheadedness, visual changes, cognitive impairment, headache, nausea, and cyanosis. In 20 cases, the initial symptoms of hypoxia occurred at cabin altitudes below 10K ft. Except for the two in-flight hypoxia episodes that resulted in class A Flight Mishaps, the remaining episodes (97%) were successfully recognized and treated by the aircrew themselves, reinforcing the importance of ground based hypoxia training.

Learning Objectives:

1 Audience will have a better understanding of the hazards of in- flight hypoxia as it relates to oxygen systems in the F/A-18 aircraft.

Search and rescue teams from Alaska’s Joint Base Elmendorf-Richardson found wreckage of his fighter jet in the wilderness about 100 miles north of Anchorage. He did not eject from the aircraft, the Air Force has reported.

“He was the No. 1 pilot in Alaska.”

Search and recovery efforts in Alaska have been stopped.

The military grounded its fleet of F-22 Raptors: concerns about the oxygen delivery systemto pilots aboard the stealth fighter jets in May. Pilots reported “hypoxia-like” events during the flight , Sgt. Pamela Anderson, a military spokeswoman, said in May. Hypoxia is whne oxygen supply is less the required fopr the body and brain to operate properly.

The cause of Haney’s crash has not been determined and cautioned against linking the crash to the grounding of the jets, Anderson said.

contributed by The Associated Press