Exclusive: F-35 Ejection Seat Fears Ground Lightweight Pilots

WASHINGTON — Concerns about increased risk of injury to F-35 pilots during low-speed ejections have prompted the US military services to temporarily restrict pilots who weigh less than 136 pounds from flying the aircraft, Defense News has learned.

During August tests of the ejection seat, built by Martin-Baker, testers discovered an increased risk of neck injury when a lightweight pilot is flying at slower speeds. Until the problem is fixed, the services decided to restrict pilots weighing under 136 pounds from operating the plane, Maj. Gen. Jeffrey Harrigian, F-35 integration office director, told Defense News in a Tuesday interview.

“The bottom line is, they have to get into the realm where the seat allows that weight of a pilot less than 136 pounds [to] safely eject out of the airplane,” Harrigian said. “They found some areas that particularly at slower speeds they were concerned about, so that drove the restriction that we have right now.”

At least one F-35 pilot is affected by the weight restriction, according to Joint Program Office spokesman Joe DellaVedova, who added that the rule was announced Aug. 27. The issue does not affect the first and only female F-35 pilot, Lt. Col. Christina Mau, 33rd Operations Group deputy commander, he noted.

The ejection seat issue is not related to the new Generation 3 helmet, built by Rockwell Collins and delivered to the JPO in August, DellaVedova said.

In August, testers discovered that when a lighter pilot is flying the aircraft, the ejection seat slightly over-rotates, Col. Todd Canterbury, who was commander of the 33rd Fighter Wing until June, told Defense News on Wednesday. The team is concerned that when the parachute opens, a lightweight pilot may not be in the optimal body position to eject out of the plane, he said.

“It’s that light pilot and the center of gravity of the seat,” said Canterbury, who flew F-35 software versions 1B, 2A, 3i and 2B. “It all has to do with getting that center of gravity kind of located within the window, we call it, for safe seat-man separation.”

Canterbury stressed that the weight restriction is an interim fix, and the JPO is working closely with aircraft builder Lockheed Martin and Martin-Baker on a permanent solution.

Pilot safety is the services’ top priority, officials stressed.

“Safety is our No. 1 concern and we want to make sure that we give the warfighter the safest ejection seat capable out there,” Canterbury, now the chief of the F-35 Integration Office Operations Division, said on Tuesday. “As we discover things, we can weigh the risk of what’s acceptable and what’s not, and right now, until we fully understand the implication of the seat, safety is our No. 1 priority.”

The JPO, Martin-Baker and Lockheed Martin are working “seven days a week, 24 hours a day” to lift the restriction, DellaVedova said. Like most modern fighter jets, the F-35’s ejection seat is meant to accommodate pilots who weigh 103 pounds to 245 pounds.

“That’s our plan, that’s the requirement, and that’s what were working with the program office on,” Harrigian said.