{"id":23165,"date":"2019-02-12T02:25:29","date_gmt":"2019-02-12T02:25:29","guid":{"rendered":"https:\/\/one.sightlinemg.com\/defensenews\/uncategorized\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/"},"modified":"2026-08-07T20:44:54","modified_gmt":"2026-08-07T20:44:54","slug":"breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix","status":"publish","type":"post","link":"https:\/\/one.sightlinemg.com\/defensenews\/air\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/","title":{"rendered":"Breathing easier: After years of T-6 hypoxia scares, the Air Force thinks it has the fix"},"content":{"rendered":"\n

For instructor pilot Maj. Kinsley \u201cTrigger\u201d Jordan, the first clue that something had gone seriously wrong was when he suddenly tasted something metallic.<\/p>\n\n\n\n

Jordan was in a T-6 Texan II, on the back half of a routine training sortie with a student pilot near Vance Air Force Base<\/a> in Oklahoma in early November 2017. The student was practicing basic touch-and-go landings at a nearby airport when Jordan became cognizant of the metallic taste. He first wondered if he hadn\u2019t eaten enough for lunch, or if he had unknowingly bit his lip and drawn blood.<\/p>\n\n\n\n

But then, Jordan looked at the T-6\u2019s instrumentation. He could see the numbers clearly, but the experienced pilot suddenly could not comprehend what the basic altitude and airspeed readings meant \u2014 and whether they were good or bad.<\/p>\n\n\n\n

\u201cThat\u2019s when the severity of what it was made me realize, \u2018I\u2019m not exactly sure what\u2019s happening right now,\u2019\u2009\u201d Jordan, who teaches flying at Vance\u2019s 33rd Flying Training Squadron, said in a Jan. 23 interview.<\/p>\n\n\n\n

Jordan had suffered either hypoxia, a lack of oxygen in his blood, or a similar \u201cunexplained physiological event<\/a>,\u201d as the Air Force calls it. It was one of the first in a series of incidents that led Vance\u2019s 71st Flying Training Wing to temporarily ground its T-6s.<\/p>\n\n\n\n

A month-long, fleet-wide grounding of T-6s<\/a> followed early in 2018, and an alarmed Air Force scrambled to solve the mystery of why its most basic training aircraft was putting dozens of student and instructor pilots at risk of passing out in mid-air \u2014 and possibly dying.<\/p>\n\n\n\n

But now, the Air Force is rolling out a series of fixes that it thinks will solve the problem once and for all \u2014 and may have already started cutting down on hypoxia and hypoxia-like incidents.<\/p>\n\n\n\n

In a Jan. 10 interview, Brig. Gen. Edward Vaughan<\/a> \u2014 the officer in charge of solving this problem and head of the Air Force Physiological Episodes Action Team \u2014 said all the changes will be in place by fiscal 2023 at the latest, though the Air Force is making faster progress than expected and he\u2019s optimistic it could get done sooner.<\/p>\n\n\n\n

\"\"
The Air Force had to scramble to solve the mystery of why its most basic training aircraft was putting dozens of student and instructor pilots at risk. (Lt. Col. Ternell Washington\/Air Force)<\/figcaption><\/figure>\n\n\n\n

Key to the Air Force\u2019s effort is a completely redesigned On-Board Oxygen Generating System, or OBOGS, that takes design ideas from the F-15E Strike Eagle, in which hypoxia is virtually unheard of, and from the A-10 Warthog.<\/p>\n\n\n\n

The Air Force is also taking maintenance cues from the Navy, which service officials thinks are helping, though they\u2019re continuing to study those changes. In all, Vaughan said, the Air Force has a slate of about 20 changes it\u2019s making to the T-6. And some of those changes could also be adapted to other aircraft as well, to further reduce the likelihood of their pilots suffering hypoxia or other episodes.<\/p>\n\n\n\n

An insidious threat<\/b><\/p>\n\n\n\n

Besides hypoxia, unexplained physiological events, or UPEs, can include hypocapnia, a lack of carbon dioxide in the blood. They can cause problems such as shortness of breath, dizziness or disorientation, or even loss of consciousness \u2014 and when pilots suffer them, the results can be dangerous or even deadly.<\/p>\n\n\n\n

It can be one of the most insidious dangers a pilot can face, said retired Gen. Hawk Carlisle<\/a> in a Jan. 22 interview. The former head of Air Combat Command flew F-15s. Hypoxia, he said, sneaks up so slowly that the pilot often doesn\u2019t realize what\u2019s happening until the condition becomes serious.<\/p>\n\n\n\n

Carlisle, now president of the National Defense Industrial Association, said he once became hypoxic during a nighttime training flight in an F-15C Eagle that had a leaky oxygen hose. The flight happened in 2002 at Eglin Air Force Base in Florida, while he was the commander of the 33rd Fighter Wing.<\/p>\n\n\n\n

Carlisle suddenly couldn\u2019t see clearly, and his first reaction was to wonder what had gone wrong with his night vision goggles. But because he had been trained to identify symptoms of hypoxia, he quickly realized what was happening wasn\u2019t a night vision problem. That training, which included purposely having hypoxia induced in a controlled situation on the ground, taught him that his vision started to suffer when he experienced hypoxia.<\/p>\n\n\n\n

Other pilots can experience hot and cold flashes or tingling in their fingers when hypoxia strikes. Wesley Hallman, a retired colonel and F-15 and F-22 pilot who is now senior vice president for policy at NDIA, said in the same Jan. 22 interview that\u2019s what he typically felt.<\/p>\n\n\n\n

Carlisle said that once he figured out he was hypoxic, he took the usual steps to resolve the problem: He declared an emergency, \u201cgang loaded\u201d his regulator to turn the oxygen all the way up and descended so the ambient air coming in would be more oxygen-rich. Pilots experiencing hypoxia must get below 18,000 feet, he said, though it\u2019s best to get below 10,000 feet.<\/p>\n\n\n\n

\u201cAlmost instantaneously, I went, \u2018Oh! There\u2019s my vision coming back,\u2019\u2009\u201d Carlisle said. \u201cThe recovery is pretty dramatic. Once you get oxygen, it comes back pretty rapidly.\u201d<\/p>\n\n\n\n

The Air Force was unable to provide statistics on hypoxia rates by press time.<\/p>\n\n\n\n

\"\"
Brig. Gen. Ed “Hertz” Vaughan and maintainers with the 12th Flying Training Wing examine a T-6’s On-Board Oxygen Generating System at Randolph Air Force Base, Texas.<\/figcaption><\/figure>\n\n\n\n

Carlisle estimates he had five or six experiences with hypoxia or a similar condition over his career and said it\u2019s extremely common.<\/p>\n\n\n\n

\u201cAnybody that flies a fighter that says they haven\u2019t is lying,\u201d Carlisle said.<\/p>\n\n\n\n

Once the immediate danger of hypoxia or a similar incident has passed and the pilot reflects on what just happened, Carlisle and Hallman said, the experience is frightening.<\/p>\n\n\n\n

\u201cYou recover very quickly, but once you do recover, you\u2019re like, \u2018That wasn\u2019t good,\u2019\u2009\u201d Hallman said. \u201cIt\u2019s so insidious, and there\u2019s nothing you can do, once you get to unconsciousness.\u201d<\/p>\n\n\n\n

Carlisle said he lost a wingman in Germany during a high-altitude training flight in F-15s in 1982, after the other pilot lost consciousness due to hypoxia. Carlisle said he radioed his experienced wingman, Jeff \u201cWedge\u201d Roether, to climb. Roether hit the afterburners and pulled his nose up.<\/p>\n\n\n\n

That was the last thing Roether ever did before losing consciousness, Carlisle said. His F-15 peaked at 37,000 feet and then plunged into the ground, with full afterburners. The accident investigation board concluded hypoxia was to blame, he said.<\/p>\n\n\n\n

\u201cYou know what can happen,\u201d Carlisle said. \u201cEvery time I had a hypoxic incident, I went back, I wrote it down, I thought about what I felt like going into it, just to make sure I was conscious of what my indications were, so if it happened again, I would be ready to recover. Because you know it can sneak up on you.\u201d<\/p>\n\n\n\n

When Jordan had his scare in 2017, he was about to tell the student pilot they needed to bail out. But just then, he saw the runway, and realized they were in good shape.<\/p>\n\n\n\n

\u201cEven though I couldn\u2019t understand what [the instruments] were telling me, something about the runway and where we were looked OK,\u201d Jordan said.<\/p>\n\n\n\n

The student pilot said he felt fine, so they lined up for a landing, touched down \u2014 and then the student pilot took off again.<\/p>\n\n\n\n

\u201cMy mind was screaming, \u2018No! Why didn\u2019t we stop?\u2019\u201d Jordan said. \u201cAnd I realized I never told the student, \u2018Make this a full stop.\u2019 My thinking was slow, my cognition of what was going on was slow. I wasn\u2019t incapacitated, but it was hard to reason the simple, everyday tasks that an instructor pilot does in the aircraft. And I didn\u2019t realize that until after the fact.\u201d<\/p>\n\n\n\n

Jordan dropped his mask, and after breathing ambient air for about 30 seconds, his faculties started coming back and things began to make sense again. He radioed in an emergency, they turned back to Vance and Jordan landed the T-6 safely.<\/p>\n\n\n\n

A new OBOGS<\/b><\/p>\n\n\n\n

The incidents at Vance were among the first in a series of hypoxic and hypoxic-like episodes that plagued the T-6 fleet. Five pilots at Vance, including Jordan, reported hypoxia-like symptoms during four flights, leading to the November 2017 grounding for three weeks.<\/p>\n\n\n\n

Concerns began to mount, and frustrations grew, as the episodes continued without a solution in sight. In January 2018, the 19th Air Force suspended all T-6 solo flights and authorized pilots to fly with their masks down, so they could breathe cockpit air and reduce the risks of hypoxia. After the wave of physiological episodes the last week of that month, the Air Force grounded all T-6 flights for all of February and launched a serious effort to figure out what was wrong.<\/p>\n\n\n\n

In early February 2018, Rep. Michael Turner, R-Ohio, lambasted Lt. Gen. Mark Nowland<\/a>, then-deputy chief of staff for operations, for suggesting that training would be an important part of fixing the problem, implying that the onus was on pilots rather than the Air Force.<\/p>\n\n\n\n

\u201cShould we start doing hearing training where we ask you to come before us and then let\u2019s have you hold your breath for a minute in the first hearing, and then in the second hearing we\u2019ll have you hold your breath for two minutes?\u201d Turner said. \u201cIt makes no sense.\u201d<\/p>\n\n\n\n

Nowland swiftly clarified he was not blaming pilots.<\/p>\n\n\n\n

After months of study, the Air Force concluded that the physiological episodes were caused by rapidly fluctuating oxygen concentrations in the T-6. It wasn\u2019t happening all the time, Vaughan said, or even most of the time, which made the problem tricky to pin down.<\/p>\n\n\n\n

One thing the Air Force learned from consulting with the Navy is that periodically purging moisture from the OBOGS \u2014 as the Navy does every two weeks \u2014 might cut down on UPEs. Some maintainers and experts from the Air Force Research Laboratory believe the buildup of moisture over time degrades the OBOGS\u2019 performance.<\/p>\n\n\n\n

The Air Force has been purging moisture regularly for the past few months, and Vaughan said there are signs that it\u2019s helping. The Air Force is also experimenting with moisture purges at different intervals \u2014 for example, some T-6s have weekly purges, others are purged every three weeks or so \u2014 to see which is most effective.<\/p>\n\n\n\n

The Air Force is also in the midst of some long-overdue hardware upgrades to the T-6\u2019s OBOGS. A new oxygen concentrator has been designed, Vaughan said, and deliveries began in December. The redesigned concentrator has new parts and materials, is built to more recent specifications, and is more reliable than the previous two-decade-old concentrator, he said. It will likely take a year to 18 months to install the new concentrators in all of the roughly 400 T-6s in the fleet, he said.<\/p>\n\n\n\n

One of the new concentrator\u2019s biggest improvements is that its software can be easily upgraded or adjusted if, for example, the Air Force decides to tweak the concentration of oxygen in the cockpit. This is similar to how engine software is upgraded today, Vaughan said.<\/p>\n\n\n\n

The old concentrator wasn\u2019t designed to accept software adjustments, Vaughan said, so maintainers would have to physically take the concentrator out of the plane and basically \u201cbreak\u201d the device to hack in the new software.<\/p>\n\n\n\n

A closer look<\/b><\/p>\n\n\n\n

Vaughan said that the AFPEAT group also took a closer look at the F-15E Strike Eagle, to figure out what it was doing right \u2014 and it learned a lot.<\/p>\n\n\n\n

\u201cIf you look back over the years, the F-15E Strike Eagle \u2026 has virtually none of these UPEs,\u201d Vaughan said. \u201cWhen they have a physiological episode in a Strike Eagle, it\u2019s very well known that this part failed, or there was some type of a mishap \u2014 it\u2019s very attributable. We looked at the F-15E and said, what is it about that OBOGS system that makes it so reliable and effective that we can apply to the T-6?\u201d<\/p>\n\n\n\n

The Strike Eagle\u2019s OBOGS has about a half-dozen features that could be applied to the T-6, and possibly other planes as well, Vaughan said.<\/p>\n\n\n\n

For example, the Strike Eagle has a moisture separator upstream from the OBOGS, as does the A-10 Warthog. Adding one to the T-6 could help cut down on UPEs, Vaughan said. The Air Force could end up transplanting a Warthog moisture separator into the T-6, with only a few tweaks, because the specifications of the Warthog are close enough to the T-6. That would mean the Air Force wouldn\u2019t have to go to the effort and expense of designing a new one.<\/p>\n\n\n\n

\"\"
The Air Force is completely redesigning its On-Board Oxygen Generating System, or OBOGS, taking cues from the F-15E Strike Eagle, in which hypoxia is virtually unheard of, and from the A-10 Warthog. (Staff Sgt. Joe McFadden\/Air Force)<\/figcaption><\/figure>\n\n\n\n

Another main difference is that the F-15E has an automatic backup oxygen system included in its OBOGS \u2014 basically a second pair of oxygen tanks in reserve, for when its pilots push the limit and need more help breathing.<\/p>\n\n\n\n

Vaughan said the Air Force is designing a similar backup system for the T-6, which now has a two-tank OBOGS, and he expects a prototype to be ready in a year.<\/p>\n\n\n\n

But, he cautioned, it\u2019s not certain the Air Force will move forward with the four-tank OBOGS for the T-6. If the other changes on their own eliminate the unexplained physiological episodes, the Air Force could decide it\u2019s not worth the investment to field the backup tanks.<\/p>\n\n\n\n

The T-6 will also get more sensors to better track how oxygen is flowing to the pilot, Vaughan said. The T-6 OBOGS currently has sensors that measure whether it\u2019s producing oxygen, how much, and if the system is meeting its requirements, he said. But it doesn\u2019t have sensors that show if the oxygen is flowing all the way to the pilot\u2019s mask and regulator, like the Strike Eagle does, which could alert the pilot if there\u2019s a leak in a hose or other problem.<\/p>\n\n\n\n

When all is said and done, Vaughan said, the T-6 OBOGS will be almost entirely replaced, save for a few standard pipes and hoses. The oxygen concentrator upgrade alone accounts for 80 percent of the OBOGS, he said.<\/p>\n\n\n\n

After the hypoxia wave began, pilots at Vance began talking to each other regularly about what they were experiencing, Jordan said, as well as their uncertainty about what was causing the problems. Jordan said it was great that talking about it became a cultural norm.<\/p>\n\n\n\n

But recently, those conversations have all but dried up, which Jordan sees as a sign of progress.<\/p>\n\n\n\n

\u201cWe don\u2019t see what we were seeing a year ago,\u201d he said. \u201cIt\u2019s not a taboo topic at all. [But today] we don\u2019t talk about it, because it\u2019s just not happening that much anymore.\u201d<\/p>\n\n\n\n

Carlisle said the Air Force is likely on the right track with the maintenance, hardware and software upgrades to solve the unexplained hypoxia problem. Training is also vital, he said, so that pilots are able to recognize the symptoms of a physiological episode before it becomes too dangerous. Carlisle said he has no doubt Air Education and Training Command will continue to push hypoxia training.<\/p>\n\n\n\n

But the fact that pilots are flying fewer hours, on average, than in previous years is worrisome, Carlisle said. The lack of more time in the cockpit could place them in greater jeopardy if a physiological episode develops. Pilots are spending more time in simulators, he said, but even the best simulators can\u2019t prepare a pilot for how he will react if he\u2019s suddenly faced with a life-and-death hypoxic situation.<\/p>\n\n\n\n

Pilots can get anxious and upset and make mistakes in the heat of the moment, he said. But the more a pilot flies, the more comfortable he is, and he\u2019s more likely to recognize even small changes in his environment alerting him that something\u2019s wrong.<\/p>\n\n\n\n

\u201cA simulator\u2019s great training, you need it,\u201d Carlisle said. \u201cBut a simulator never killed anybody.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"

The Air Force is rolling out a series of fixes that it thinks will solve the problem once and for all \u2014 and may have already started cutting down on hypoxia and hypoxia-like incidents<\/p>\n","protected":false},"author":7,"featured_media":51348,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_yoast_wpseo_meta-robots-noindex":"","_yoast_wpseo_meta-robots-nofollow":"","_yoast_wpseo_canonical":"","_acf":"","_yoast_wpseo_primary_category":7,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","_smg_distribution_targets":[]},"categories":[7,160,36],"tags":[],"coauthors":[3412],"class_list":["post-23165","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-air","category-daily-news-roundup","category-newsletters"],"acf":{"subheadline":"","legacy_arc_id":"XBRRFGGDVNB2BCMUAMPMWP55PE","arc_canonical_url":"\/news\/your-air-force\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/","remove_feature_photo":false,"is_sponsored":false,"subtype":"","redirect_url":"","disable_inline_ads":false,"native_logo_pretext":"Presented By:"},"yoast_head":"\nBreathing easier: After years of T-6 hypoxia scares, the Air Force thinks it has the fix - Defense News<\/title>\n<meta name=\"description\" content=\"The Air Force is rolling out a series of fixes that it thinks will solve the problem once and for all \u2014 and may have already started cutting down on hypoxia and hypoxia-like incidents\" \/>\n<meta name=\"robots\" content=\"noindex, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Breathing easier: After years of T-6 hypoxia scares, the Air Force thinks it has the fix\" \/>\n<meta property=\"og:description\" content=\"The Air Force is rolling out a series of fixes that it thinks will solve the problem once and for all \u2014 and may have already started cutting down on hypoxia and hypoxia-like incidents\" \/>\n<meta property=\"og:url\" content=\"https:\/\/one.sightlinemg.com\/defensenews\/air\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/\" \/>\n<meta property=\"og:site_name\" content=\"Defense News\" \/>\n<meta property=\"article:published_time\" content=\"2019-02-12T02:25:29+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2026-08-07T20:44:54+00:00\" \/>\n<meta name=\"author\" content=\"Stephen Losey\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Stephen Losey\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"13 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\n\t \"@context\": \"https:\\\/\\\/schema.org\",\n\t \"@graph\": [\n\t {\n\t \"@type\": \"Article\",\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/air\\\/2019\\\/02\\\/12\\\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\\\/#article\",\n\t \"isPartOf\": {\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/air\\\/2019\\\/02\\\/12\\\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\\\/\"\n\t },\n\t \"author\": {\n\t \"name\": \"migration\",\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/#\\\/schema\\\/person\\\/cc76c831bb37a926738c8391fca7a3b1\"\n\t },\n\t \"headline\": \"Breathing easier: After years of T-6 hypoxia scares, the Air Force thinks it has the fix\",\n\t \"datePublished\": \"2019-02-12T02:25:29+00:00\",\n\t \"dateModified\": \"2026-08-07T20:44:54+00:00\",\n\t \"mainEntityOfPage\": {\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/air\\\/2019\\\/02\\\/12\\\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\\\/\"\n\t },\n\t \"wordCount\": 2712,\n\t \"commentCount\": 0,\n\t \"publisher\": {\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/#organization\"\n\t },\n\t \"image\": {\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/air\\\/2019\\\/02\\\/12\\\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\\\/#primaryimage\"\n\t },\n\t \"thumbnailUrl\": \"https:\\\/\\\/one.sightlinemg.com\\\/wp-content\\\/uploads\\\/2026\\\/08\\\/hypoxia_main.JPG.jpg\",\n\t \"articleSection\": [\n\t \"Air Warfare\",\n\t \"Daily News Roundup\",\n\t \"Newsletters\"\n\t ],\n\t \"inLanguage\": \"en-US\",\n\t \"potentialAction\": [\n\t {\n\t \"@type\": \"CommentAction\",\n\t \"name\": \"Comment\",\n\t \"target\": [\n\t \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/air\\\/2019\\\/02\\\/12\\\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\\\/#respond\"\n\t ]\n\t }\n\t ]\n\t },\n\t {\n\t \"@type\": \"WebPage\",\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/air\\\/2019\\\/02\\\/12\\\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\\\/\",\n\t \"url\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/air\\\/2019\\\/02\\\/12\\\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\\\/\",\n\t \"name\": \"Breathing easier: After years of T-6 hypoxia scares, the Air Force thinks it has the fix - Defense News\",\n\t \"isPartOf\": {\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/#website\"\n\t },\n\t \"primaryImageOfPage\": {\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/air\\\/2019\\\/02\\\/12\\\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\\\/#primaryimage\"\n\t },\n\t \"image\": {\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/air\\\/2019\\\/02\\\/12\\\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\\\/#primaryimage\"\n\t },\n\t \"thumbnailUrl\": \"https:\\\/\\\/one.sightlinemg.com\\\/wp-content\\\/uploads\\\/2026\\\/08\\\/hypoxia_main.JPG.jpg\",\n\t \"datePublished\": \"2019-02-12T02:25:29+00:00\",\n\t \"dateModified\": \"2026-08-07T20:44:54+00:00\",\n\t \"description\": \"The Air Force is rolling out a series of fixes that it thinks will solve the problem once and for all \u2014 and may have already started cutting down on hypoxia and hypoxia-like incidents\",\n\t \"breadcrumb\": {\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/air\\\/2019\\\/02\\\/12\\\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\\\/#breadcrumb\"\n\t },\n\t \"inLanguage\": \"en-US\",\n\t \"potentialAction\": [\n\t {\n\t \"@type\": \"ReadAction\",\n\t \"target\": [\n\t \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/air\\\/2019\\\/02\\\/12\\\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\\\/\"\n\t ]\n\t }\n\t ]\n\t },\n\t {\n\t \"@type\": \"ImageObject\",\n\t \"inLanguage\": \"en-US\",\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/air\\\/2019\\\/02\\\/12\\\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\\\/#primaryimage\",\n\t \"url\": \"https:\\\/\\\/one.sightlinemg.com\\\/wp-content\\\/uploads\\\/2026\\\/08\\\/hypoxia_main.JPG.jpg\",\n\t \"contentUrl\": \"https:\\\/\\\/one.sightlinemg.com\\\/wp-content\\\/uploads\\\/2026\\\/08\\\/hypoxia_main.JPG.jpg\"\n\t },\n\t {\n\t \"@type\": \"BreadcrumbList\",\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/air\\\/2019\\\/02\\\/12\\\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\\\/#breadcrumb\",\n\t \"itemListElement\": [\n\t {\n\t \"@type\": \"ListItem\",\n\t \"position\": 1,\n\t \"name\": \"Home\",\n\t \"item\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/\",\n\t \"ad_zone\": \"home\"\n\t },\n\t {\n\t \"@type\": \"ListItem\",\n\t \"position\": 2,\n\t \"name\": \"Air Warfare\",\n\t \"item\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/air\\\/\",\n\t \"ad_zone\": \"air\"\n\t },\n\t {\n\t \"@type\": \"ListItem\",\n\t \"position\": 3,\n\t \"name\": \"Breathing easier: After years of T-6 hypoxia scares, the Air Force thinks it has the fix\"\n\t }\n\t ]\n\t },\n\t {\n\t \"@type\": \"WebSite\",\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/#website\",\n\t \"url\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/\",\n\t \"name\": \"Defense News\",\n\t \"description\": \"Covering the politics, business and technology of defense | Defense News\",\n\t \"publisher\": {\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/#organization\"\n\t },\n\t \"potentialAction\": [\n\t {\n\t \"@type\": \"SearchAction\",\n\t \"target\": {\n\t \"@type\": \"EntryPoint\",\n\t \"urlTemplate\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/?s={search_term_string}\"\n\t },\n\t \"query-input\": {\n\t \"@type\": \"PropertyValueSpecification\",\n\t \"valueRequired\": true,\n\t \"valueName\": \"search_term_string\"\n\t }\n\t }\n\t ],\n\t \"inLanguage\": \"en-US\"\n\t },\n\t {\n\t \"@type\": \"Organization\",\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/#organization\",\n\t \"name\": \"Defense News\",\n\t \"url\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/\",\n\t \"logo\": {\n\t \"@type\": \"ImageObject\",\n\t \"inLanguage\": \"en-US\",\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/#\\\/schema\\\/logo\\\/image\\\/\",\n\t \"url\": \"https:\\\/\\\/one.sightlinemg.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/defensenews-logo-white.png\",\n\t \"contentUrl\": \"https:\\\/\\\/one.sightlinemg.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/defensenews-logo-white.png\",\n\t \"caption\": \"Defense News\"\n\t },\n\t \"image\": {\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/#\\\/schema\\\/logo\\\/image\\\/\"\n\t }\n\t },\n\t {\n\t \"@type\": \"Person\",\n\t \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/#\\\/schema\\\/person\\\/cc76c831bb37a926738c8391fca7a3b1\",\n\t \"name\": \"migration\",\n\t \"image\": {\n\t \"@type\": \"ImageObject\",\n\t \"inLanguage\": \"en-US\",\n\t \"@id\": \"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/9e8d47be443ce94ce7fc357677b5f9c70235bb1f59e7267a102a74af58c04f59?s=96&d=mm&r=gcf4cb6ee0ec29e49e7a963234e4340ec\",\n\t \"url\": \"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/9e8d47be443ce94ce7fc357677b5f9c70235bb1f59e7267a102a74af58c04f59?s=96&d=mm&r=g\",\n\t \"contentUrl\": \"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/9e8d47be443ce94ce7fc357677b5f9c70235bb1f59e7267a102a74af58c04f59?s=96&d=mm&r=g\",\n\t \"caption\": \"migration\"\n\t },\n\t \"url\": \"https:\\\/\\\/one.sightlinemg.com\\\/defensenews\\\/author\\\/migration\\\/\"\n\t }\n\t ]\n\t}<\/script>\n<!-- \/ Yoast SEO Premium plugin. -->","yoast_head_json":{"title":"Breathing easier: After years of T-6 hypoxia scares, the Air Force thinks it has the fix - Defense News","description":"The Air Force is rolling out a series of fixes that it thinks will solve the problem once and for all \u2014 and may have already started cutting down on hypoxia and hypoxia-like incidents","robots":{"index":"noindex","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"og_locale":"en_US","og_type":"article","og_title":"Breathing easier: After years of T-6 hypoxia scares, the Air Force thinks it has the fix","og_description":"The Air Force is rolling out a series of fixes that it thinks will solve the problem once and for all \u2014 and may have already started cutting down on hypoxia and hypoxia-like incidents","og_url":"https:\/\/one.sightlinemg.com\/defensenews\/air\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/","og_site_name":"Defense News","article_published_time":"2019-02-12T02:25:29+00:00","article_modified_time":"2026-08-07T20:44:54+00:00","author":"Stephen Losey","twitter_card":"summary_large_image","twitter_misc":{"Written by":"Stephen Losey","Est. reading time":"13 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/one.sightlinemg.com\/defensenews\/air\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/#article","isPartOf":{"@id":"https:\/\/one.sightlinemg.com\/defensenews\/air\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/"},"author":{"name":"migration","@id":"https:\/\/one.sightlinemg.com\/defensenews\/#\/schema\/person\/cc76c831bb37a926738c8391fca7a3b1"},"headline":"Breathing easier: After years of T-6 hypoxia scares, the Air Force thinks it has the fix","datePublished":"2019-02-12T02:25:29+00:00","dateModified":"2026-08-07T20:44:54+00:00","mainEntityOfPage":{"@id":"https:\/\/one.sightlinemg.com\/defensenews\/air\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/"},"wordCount":2712,"commentCount":0,"publisher":{"@id":"https:\/\/one.sightlinemg.com\/defensenews\/#organization"},"image":{"@id":"https:\/\/one.sightlinemg.com\/defensenews\/air\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/#primaryimage"},"thumbnailUrl":"https:\/\/one.sightlinemg.com\/wp-content\/uploads\/2026\/08\/hypoxia_main.JPG.jpg","articleSection":["Air Warfare","Daily News Roundup","Newsletters"],"inLanguage":"en-US","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/one.sightlinemg.com\/defensenews\/air\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/#respond"]}]},{"@type":"WebPage","@id":"https:\/\/one.sightlinemg.com\/defensenews\/air\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/","url":"https:\/\/one.sightlinemg.com\/defensenews\/air\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/","name":"Breathing easier: After years of T-6 hypoxia scares, the Air Force thinks it has the fix - Defense News","isPartOf":{"@id":"https:\/\/one.sightlinemg.com\/defensenews\/#website"},"primaryImageOfPage":{"@id":"https:\/\/one.sightlinemg.com\/defensenews\/air\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/#primaryimage"},"image":{"@id":"https:\/\/one.sightlinemg.com\/defensenews\/air\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/#primaryimage"},"thumbnailUrl":"https:\/\/one.sightlinemg.com\/wp-content\/uploads\/2026\/08\/hypoxia_main.JPG.jpg","datePublished":"2019-02-12T02:25:29+00:00","dateModified":"2026-08-07T20:44:54+00:00","description":"The Air Force is rolling out a series of fixes that it thinks will solve the problem once and for all \u2014 and may have already started cutting down on hypoxia and hypoxia-like incidents","breadcrumb":{"@id":"https:\/\/one.sightlinemg.com\/defensenews\/air\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/one.sightlinemg.com\/defensenews\/air\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/one.sightlinemg.com\/defensenews\/air\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/#primaryimage","url":"https:\/\/one.sightlinemg.com\/wp-content\/uploads\/2026\/08\/hypoxia_main.JPG.jpg","contentUrl":"https:\/\/one.sightlinemg.com\/wp-content\/uploads\/2026\/08\/hypoxia_main.JPG.jpg"},{"@type":"BreadcrumbList","@id":"https:\/\/one.sightlinemg.com\/defensenews\/air\/2019\/02\/12\/breathing-easier-after-years-of-t-6-hypoxia-scares-the-air-force-thinks-it-has-the-fix\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/one.sightlinemg.com\/defensenews\/","ad_zone":"home"},{"@type":"ListItem","position":2,"name":"Air Warfare","item":"https:\/\/one.sightlinemg.com\/defensenews\/air\/","ad_zone":"air"},{"@type":"ListItem","position":3,"name":"Breathing easier: After years of T-6 hypoxia scares, the Air Force thinks it has the fix"}]},{"@type":"WebSite","@id":"https:\/\/one.sightlinemg.com\/defensenews\/#website","url":"https:\/\/one.sightlinemg.com\/defensenews\/","name":"Defense News","description":"Covering the politics, business and technology of defense | Defense News","publisher":{"@id":"https:\/\/one.sightlinemg.com\/defensenews\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/one.sightlinemg.com\/defensenews\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/one.sightlinemg.com\/defensenews\/#organization","name":"Defense News","url":"https:\/\/one.sightlinemg.com\/defensenews\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/one.sightlinemg.com\/defensenews\/#\/schema\/logo\/image\/","url":"https:\/\/one.sightlinemg.com\/wp-content\/uploads\/2026\/06\/defensenews-logo-white.png","contentUrl":"https:\/\/one.sightlinemg.com\/wp-content\/uploads\/2026\/06\/defensenews-logo-white.png","caption":"Defense News"},"image":{"@id":"https:\/\/one.sightlinemg.com\/defensenews\/#\/schema\/logo\/image\/"}},{"@type":"Person","@id":"https:\/\/one.sightlinemg.com\/defensenews\/#\/schema\/person\/cc76c831bb37a926738c8391fca7a3b1","name":"migration","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/secure.gravatar.com\/avatar\/9e8d47be443ce94ce7fc357677b5f9c70235bb1f59e7267a102a74af58c04f59?s=96&d=mm&r=gcf4cb6ee0ec29e49e7a963234e4340ec","url":"https:\/\/secure.gravatar.com\/avatar\/9e8d47be443ce94ce7fc357677b5f9c70235bb1f59e7267a102a74af58c04f59?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/9e8d47be443ce94ce7fc357677b5f9c70235bb1f59e7267a102a74af58c04f59?s=96&d=mm&r=g","caption":"migration"},"url":"https:\/\/one.sightlinemg.com\/defensenews\/author\/migration\/"}]}},"jetpack_sharing_enabled":true,"distributor_meta":false,"distributor_terms":false,"distributor_media":false,"distributor_original_site_name":"Defense News","distributor_original_site_url":"https:\/\/one.sightlinemg.com\/defensenews","push-errors":false,"jetpack_featured_media_url":"https:\/\/one.sightlinemg.com\/wp-content\/uploads\/2026\/08\/hypoxia_main.JPG.jpg","_links":{"self":[{"href":"https:\/\/one.sightlinemg.com\/defensenews\/wp-json\/wp\/v2\/posts\/23165","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/one.sightlinemg.com\/defensenews\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/one.sightlinemg.com\/defensenews\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/one.sightlinemg.com\/defensenews\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/one.sightlinemg.com\/defensenews\/wp-json\/wp\/v2\/comments?post=23165"}],"version-history":[{"count":1,"href":"https:\/\/one.sightlinemg.com\/defensenews\/wp-json\/wp\/v2\/posts\/23165\/revisions"}],"predecessor-version":[{"id":23169,"href":"https:\/\/one.sightlinemg.com\/defensenews\/wp-json\/wp\/v2\/posts\/23165\/revisions\/23169"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/one.sightlinemg.com\/defensenews\/wp-json\/wp\/v2\/posts\/51348"}],"wp:attachment":[{"href":"https:\/\/one.sightlinemg.com\/defensenews\/wp-json\/wp\/v2\/media?parent=23165"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/one.sightlinemg.com\/defensenews\/wp-json\/wp\/v2\/categories?post=23165"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/one.sightlinemg.com\/defensenews\/wp-json\/wp\/v2\/tags?post=23165"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/one.sightlinemg.com\/defensenews\/wp-json\/wp\/v2\/coauthors?post=23165"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}