HILL AFB, Utah --- After a discovery of faulty insulation on coolant lines caused a temporary flight restriction for 10 F-35A Lightning IIs at Hill Air Force Base, the repaired jets are beginning to fly again.
Two aircraft returned to flight Oct. 24 and three more are scheduled for completion by Nov. 4.
Maintainers from the 388th and 419th Fighter Wings are not only involved in the repair process, but also sustain flying operations with a limited number of operational aircraft.
“This coolant line issue is not preventing us from flying our other aircraft. We’re still flying, and exercising combat generations and turning our aircraft,” said Col. Michael Miles, the 388th Maintenance Group commander. “We have a combat-capability blueprint and nothing has prevented us from pursuing that.”
In September, out of an “abundance of caution,” the Air Force announced it had decided to repair 57 F-35As that had faulty coating on avionics cooling lines installed in the fuel tank.
To repair the 10 aircraft at Hill AFB, Airmen first remove fuel and paneling from the jet. A field-team of contract maintainers cuts pre-engineered holes in the aircraft skin to access specific points in the fuel tank. The team then strips the faulty coating from the coolant lines and installs screens to prevent any foreign object from clogging the fuel siphon-tubes. After the repair, the aircraft skin and low-observable coating is restored and Airmen complete operational checks on the aircraft before returning it to service.
As the team worked on the first pair of jets, Hill’s fighter wings were left with only five operational F-35As.
"With fewer jets to fly, that impacts sorties and training opportunities for pilots," said Col. Jason Rueschhoff, the 388th Operations Group commander. "But, we've been working closely with Luke AFB, Arizona; Eglin AFB, Florida; and Nellis AFB, Nevada, sending some of our pilots there to use any additional F-35 flying capacity those bases can make available to help maintain our pilots' proficiency."
Maintainers at Hill AFB are pushing themselves and the operational aircraft to provide additional sorties.
“We’re triple-turning our aircraft. We’re hot-pitting (refueling with the engine running) and flying them three times a day. Normally, the most a fighter wing will turn their aircraft is twice a day,” Miles said.
Recently, maintainers have been able to provide the wing’s operational F-35s for 95 percent of scheduled sorties, compared to 87 percent for legacy fighters, Miles said, which highlights the proficiency of the maintenance cadre and the reliability of the fifth-generation aircraft when in service.
Maintainers with the 388th and 419th FWs say that all 10 affected jets at Hill AFB will return to service before the end of the year.
Hill AFB received its first operational F-35 in September 2015 and is slated for three operational F-35 squadrons and a total of 78 aircraft by the end of 2019. The 388th and 419th FWs fly and maintain the Air Force’s newest fighter jet in a Total Force partnership, which capitalizes on the strengths of the active duty and Reserve components.