HILL AIR FORCE BASE — The Air Force says the F-35 can now fly in lightning storms, which seems appropriate, considering the next-generation fighter jet is named after that same weather element.
The F-35 Lightning II program office says a problem with the jet’s electrical and fuel tank systems has been fixed, removing restrictions that at one time prohibited the plane from flying within 25 miles of the nearest lightning storm.
Testifying before the House Armed Services Committee on April 14, Air Force Lt. Gen. Christopher Bogdan said the formerly unresolved safety risk, identified in a report earlier this year by the Defense Department’s Director of Operational Test and Evaluation, is no longer impeding the now $1.4 trillion program’s progress.
“We had a problem with lightning,” Bogdan said. “We were having a problem qualifying the airplane to fly in lightning, (but) that problem is basically behind us.”
As proof, Bogdan offered the committee an anecdote about an F-35 being tested two weeks before at Florida’s Eglin Air Force Base. The plane was hit by lightning, but apparently with no damaging effects.
“It was in clear air and it was struck by lightning, and absolutely nothing bad happened to the airplane. The pilot landed the airplane (with) no warnings and cautions, no problems. We could see where the lightning went into the right wingtip and came out.”
According to the report, the F-35 did not “maintain residual inerting after flight for the required interval of 12 hours, which is a lightning requirement.”
That function is controlled by what is known as the jet’s “On-Board Inert Gas Generation System,” which, according to the Project on Government Oversight, removes oxygen from the explosive vapor spaces inside the jet’s fuel tank system.
POGO is an independent, nonprofit organization whose stated aim is to improve transparency and accountability throughout the federal government and spent weeks analyzing the report.
The report went on to say that, if the OBIGGS issue wasn’t fixed, “Aircraft maintainers will be required to purge fuel tanks with external nitrogen more frequently or find alternative lightning strategies.”
But after redesigns of the OBIGGS and subsequent lightning-tolerance qualification testing, Bogdan says the Lightning II is lightning-ready.
“Lightning is another one we had put on the list of last year as a problem — it’s not a problem this year.”
Several other items of note were discussed at the hearing.
Bogdan addressed a June 2014 F-35 engine failure, which also occurred at Eglin and caused the jet to burst into flames. The F-35 program office instituted a series of actions that affected flight operations, like prohibiting full engine power, and grounded the jet for nearly a month.
“Last year, we had a major engine problem,” he said. “We have a solution for that problem. It’s being put into the field, and by this summer, I will have the final production of that version of that fix into the production line and that (problem) will be behind us.”
Arizona Republican Congresswoman Martha McSalley, asked about close-air support limitations of the F-35, particularly when compared with the A-10 Thunderbolt II, which is set to be retired by the Air Force.
Michael Gilmore, DOD director of operational testing, said the F-35 “has some vulnerabilities that you would have to expect a high-performance aircraft to have. The A-10 can take hits that an F-35 couldn’t take, but I don’t think the plan for having the F-35 conduct (close-air support) is equivalent in all operational aspects for the way the A-10 would.”
The F-35 remains critical to the future of Hill Air Force Base, and defense officials say the challenges won’t delay the stealth jet’s operational timeline or its arrival at Hill, which will be home to the first three operational F-35 squadrons and will begin receiving what will ultimately be a total of 72 jets late this year.