Specifically, supplying oxygen to fighter pilots has been a known quantity for well over 50 years, but somehow or other, Lockheed-Martin has been able unable to make this work on the F-35.

NASA has done a study, and found that the Joint Strike Fighter has problems not shared with other aircraft using onboard oxygen generate systems.

The F-35 office had declared this a tempest in a tea pot, which is typical for them:

Between 2011 and 2017, more than a dozen U.S. Air Force F-35 pilots reported experiencing oxygen-deprivation symptoms. NASA has obtained new information that may help solve the mystery behind these physiological episodes and wants to study the issue more deeply. But the F-35 Joint Program Office is disputing the findings.

The recently released—but not widely circulated—report from the NASA Engineering and Safety Center (NESC) pinpoints a lag time between the pilot’s breathing pattern and the aircraft’s life-support system, due to differences between mask pressure and line pressure. It is the first independent review focused on the hypoxia-like episodes reported by pilots in the Lockheed Martin F-35 for more than a decade.

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The NESC’s work builds on a 2017 report that assessed pilots’ physiological episodes in other fighter aircraft (AW&ST March 28-April 10, 2016, p. 23). That study was driven by a congressional mandate to the U.S. Navy to conduct an independent review of the episodes in Boeing F/A-18 and T-45 aircraft going back to 2009. But the mandate did not cover the F-35. The new report is part of a larger pilot-breathing assessment that includes F/A-18 and F-15D data using CRU-103 or CRU-60 breathing gear. 

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But the F-35 data set, the first of its kind, was subsequently embargoed by the Air Force, and the NASA team had to wait about a year for the service to release pilot–breathing data for independent analysis. F-35 pilots admitted in interviews with the NESC that information about breathing problems had been suppressed over concerns about protecting the program.

Bottom line:  The Pentagon wants its over-priced and under-performing mistake jet, and if a few pilots have to experience suffocation, it’s a small price to pay.