The U.S. Air Force and industry are implementing a series of modifications to the F-35A ejection seat and helmet to remove a potential safety hazard for lightweight pilots, service officials said May 15.

The ejection seat changes are being made at a rate of 14 seats per month, putting the Air Force on track to finish modifying its 107 F-35As by December or January, said Brig. Gen. Scott Pleus, director of the Air Force F-35 integration office. The modified helmet is available in pre-production now and is scheduled to move into full production this fall.

F-35A conventional Air Force variant of the Joint Strike Fighter (JSF). Photo: Air Force.
F-35A conventional Air Force variant of the Joint Strike Fighter (JSF). Photo: Air Force.

For the ejection seat, a switch is being installed to allow lightweight pilots to slightly delay the main parachute’s deployment. In addition, a head-support panel is being mounted on the parachute to prevent the pilot’s head from moving backwards during an ejection.

The helmet is being made lighter by making its clear and dark visors interchangeable in flight instead of having two visors installed at the same time. In addition, the amount of internal strapping is being reduced.

The progress on the modifications recently prompted the Air Force to lift restrictions that prevented pilots weighing less than 136 pounds from flying the F-35A. The restrictions were imposed in 2015 to address concerns that lightweight pilots could suffer neck injuries when their parachutes opened.

“I have personally briefed every single F-35 pilot in the United States Air Force and explained the problem, as well as our solutions to fix it,” Pleus told reporters at the Pentagon. “I can assure you that they are confident stepping to their aircraft every day. I personally have flown in this seat and believe, with these modifications, this is the safest seat that I’ve ever had the chance to fly.”

Lockheed Martin [LMT] is the F-35A’s prime contractor. Martin-Baker provides the US16E ejection seat and Rockville Collins [COL] supplies the Generation III Helmet Mounted Display System.

In light of the progress on the ejection seat, Lt. Gen. Arnold Bunch, military deputy in the Air Force acquisition office, said he plans to rescind a letter asking the Defense Department’s F-35 joint program office for more information about a possible alternative, the United Technologies Corp. [UTX] Advanced Concept Ejection Seat 5 (ACES 5).

In other F-35A comments, Pleus said that aircraft from low-rate initial production (LRIP) contracts seven through nine have achieved mission-capable rates in the high-80 and low-90 percentages, up from about 50 percent for LRIPs three through nine.

He also said the Air Force is trying to do a better job keeping the F-35A’s threat library up to date. He expects more progress to be made when the Block 3F software upgrade is delivered in September or October.

The Air Force has trained more than 400 pilots and accumulated more than 40,000 flight hours on the F-35A, the conventional-takeoff-and-landing variant of the F-35 Lightning II. In 2016, the service declared the F-35A ready for combat.