The U.S. Air Force’s $1.5 trillion F-35 fighter-jet program continues to suffer new technical problems—and this time, the problems potentially affect pilots’ physical safety. Five pilots at Luke Air Force Base in Arizona came down with symptoms of oxygen deprivation, which led to the Air Force grounding the whole squadron while it investigates, according to a statement the Air Force released on Friday.
“The Air Force takes these physiological incidents seriously, and our focus is on the safety and well-being of our pilots. We are taking the necessary steps to find the root cause of these incidents,” said Brig. Gen. Brook Leonard, commander of the 56th, said in the Air Force statement.
The incidents have all taken place since May 2. In each case, the aircraft’s primary oxygen-supply systems malfunctioned, but the back-up system kicked in and the pilot was able to safely land the aircraft.
This marks just the latest in a wide range of technical mishaps that have bedeviled the F-35’s developers. Past issues have included trouble with the ejection-seat mechanism and the on-board navigation, among other systems and features.
The Air Force has taken criticism for all of these issues, in part because the F-35 program is the most expensive weapons program in military history. The Air Force has been pursuing the F-35 concept for nearly a decade, in part because it would be a uniquely all-purpose aircraft that could, with adjustments, take off and land on an aircraft carrier or a ground-based landing strip. No current fighter jet has these capabilities.
In the meantime, however, Israel has bought several F-35s from the United States, and French intelligence sources reported recently that Israel flew them in successful air strikes in Syria. The U.S. Air Force is expected to take some of its own F-35s to Paris later this month and fly them in the Paris Air Show.