The US Air Force will once again be able to fly its F-35 stealth fighters through thunderstorms or lightning following a fuel system upgrade.
The service’s F-35As could resume unrestricted flight for the first time in nearly two years once all jets have been repaired. The Air Force Times quoted Laura Seal, spokeswoman for the F-35 Lightning II Joint Program Office, as saying that if upgrades go as planned, the first F-35A could return to flying unrestricted by July. .
The rest will follow as they are fitted with new hardware, although Seal won’t say how many need to be changed. The Air Force had about 300 F-35As in fiscal year 2021, according to the report.
After discovering that a critical system might not operate effectively if hit by a bolt, officials banned F-35As from operating within 25 nautical miles of lightning or thunderstorms in the spring of 2020.
Fuel system problems
The repair concerns the F-35’s OBIGGS, or on-board inert gas generation system. This device is designed to pump nitrogen-enriched air into the F-35’s fuel system to prevent the formation of highly flammable vapors.
A lightning strike can ignite flammable vapors and possibly trigger an explosion if the interior of the aircraft’s main fuel tank and associated fuel lines are not kept “inert” by the OBIGGS.
As of November 2020, F-35 manufacturer Lockheed Martin has started integrating an improved version of OBIGGS into stealth fighters. However, the company will also have to upgrade older planes that have already been deployed. It is unclear if the upgraded OBIGGS has been introduced to the other variants currently in production.
Seal said the F-35B (the short-takeoff vertical landing variant) and F-35C (the carrier-based version) will be the next to get the upgrades, without disclosing how many planes would be needed. of this improvement.
The flight restriction, however, is expected to remain in effect until all operational jets undergo fuel system repairs, which should take place by the end of 2025. Seal says a software update scheduled for later this year will notify pilots when performance drops in the OBIGG system. are noticed.
“The root cause of the nitrogen tube failures is still under investigation,” Seal told the Air Force Times. “That said, the F-35 Joint Program Office and Lockheed Martin have worked aggressively to develop and deploy an engineering fix that eliminates the issue, even as we continue to investigate the root cause of the damage in the OBIGGS configuration of ‘origin.”
In August 2021, an F-35A was struck by lightning mid-air in a previously undisclosed incident, according to Air Force Times. The aircraft’s canopy and body panels were damaged, and the repair cost between $600,000 and $2.5 million.
An investigation into the incident is ongoing. As of January 25, 15 lightning strikes had been reported by Air Force, Navy, and Marine Corps F-35 units, with each damage costing between $25,000 and $570,000 to repair.
Bloomberg reported in 2020, OBIGGS issues caused delays, causing new aircraft deliveries to halt as Lockheed Martin investigated the production line issue. Nevertheless, once it was discovered that the problem occurred after the planes were delivered, the F-35 Joint Program Office issued a lightning-related flight restriction.
The report also notes that faulty inert gas tubes were spotted in more than half of the 24 aircraft inspected. An initiative was then launched to upgrade the OBIGGS system and this was the second time in 10 years.
According to a Marine Corps request for portable lightning arresters, the outer skin of the F-35 is wrapped in a composite metal frame that does not provide fundamental passive lightning protection.
F-35s must be accompanied by lightning rods when stationed in the open at bases lacking the required infrastructure. It’s also unknown if the new OBIGGS update will make lightning rods obsolete.
“It is not known how often F-35s are struck by lightning, as the fleet is only required to report lightning strikes that result in reportable accidents,” the Joint Program Office spokesperson said. . “All of the reported strikes occurred in flight, with none affecting the pilot’s ability to fly the aircraft safely.”
Lightning protection is just another stumbling block for the plane, which has already been chastised for sky-high operational expenses and software glitches. The EurAsian Times had recently reported, citing a Pentagon report, that the software upgrade, which is installed on US F-35 fighter jets, is “immature, deficient and insufficiently tested”.