- A key F-35 safety system is sustaining damage in Air Force service, forcing the office that overseas the F-35 program to recommend flight restrictions.
- Under the new guidelines, F-35 jets should socially distance from lightning, maintaining a distance of least 25 miles.
- The faulty systems could cause a F-35 hit by lightning to literally explode in midair.
The F-35 Lightning II strike fighter is temporarily barred from flying near actual lightning. More than a dozen Air Force F-35s were discovered with damage to a system designed to prevent catastrophic damage from lightning strikes. The damaged systems place the aircraft in danger of exploding if the airplane were hit by lightning in mid-flight.
The problem is with the Onboard Inert Gas Generation System (OBIGGS) is a safety subsystem common in modern airplanes. A typical OBIGGS system diverts air from the aircraft engine and separates the nitrogen, injecting it into the jet’s fuel tanks. The more inflammable nitrogen present the less flammable oxygen, helping reduce the possibility of fuel tank explosions. Wartime damage aside, one way a fuel tank explosion might take place is as a result of a lightning strike.
Inspectors at the Air Force’s Ogden Logistics Complex discovered damage to the tubes that funnel nitrogen into the fuel tanks in 14 out of 24 out of F-35As inspected. The problem appears limited to the Air Force’s F-35A model. The U.S. Navy and Marine Corps, which operate the -C and -B versions of the F-35, have not seen similar problems.
According to Defense News, manufacturer Lockheed Martin paused F-35 deliveries to look into the issue with aircraft on the production line. The company believes that the problem is being caused “in the field after aircraft delivery” meaning while in the hands of the Air Force. There are no reports as of yet in the hands of foreign F-35 operators, though that sample size might still be pretty small so far. Air Force Magazine’s 2020 almanac lists the Air Force and Air Force Reserve as currently operating 203 Lightning II fighters, the most of any air force worldwide.
For now, the F-35 Joint Program Office, which overseas the global F-35 enterprise, is recommending that F-35As avoid lightning and thunderstorms. The jets should maintain a distance of 25 miles from either type of weather, until the source of the problem is found and a fix is implemented.
Ironically, this is the second time the Lightning II has been prohibited from flying near actual lightning, after an earlier problem was discovered with the OBIGGS in the early 2010s.
Source: Defense News.
Kyle Mizokami is a writer on defense and security issues and has been at Popular Mechanics since 2015. If it involves explosions or projectiles, he's generally in favor of it. Kyle’s articles have appeared at The Daily Beast, U.S. Naval Institute News, The Diplomat, Foreign Policy, Combat Aircraft Monthly, VICE News, and others. He lives in San Francisco.
