Martin Baker (Hall 4 Stand G110) says that a solution to a safety problem with the F-35 ejection seat is two-thirds of the way through a testing program. Lt. General Chris Bogdan, the F-35 program executive officer, said last week that the proposed fixes will meet all F-35 requirements. Bogdan met with Martin Baker (MB) here at the show, and Andrew Martin, the company’s director of business development, told AIN that the discussions went well.
The British company is the sole supplier of ejection seats to the F-35 program. Low-speed ejection testing in 2015 revealed an increased risk of neck injury for lightweight pilots because of the combination of seat rotation during the ejection phase and a heavy pilot’s helmet. Since then, pilots weighing under 136 pounds have been precluded from flying the stealth jet. Rival ejection seat maker UTA Aerospace Systems suggested that its ACES 5 product could be substituted for the US16E.
From the outset, Martin Baker had designed the US16E seat to address the heavy-helmet issue. Upon ejection, large air bags contained in the seat’s headrest would inflate to center, restrain and protect the pilot’s head. The design was qualified in December 2010 with the Elbit/Rockwell Collins Gen II helmet-mounted display. But since the seat rotation issue was discovered, MB engineers have devised two methods of alleviation, and the program office asked Elbit and Rockwell Collins to reduce the weight of the helmet. This they have done, lowering the weight of the latest Gen III helmet by six ounces.
One of the two seat fixes is quite simple: a head support panel made of woven fabric fills the gap between the risers as the seat operates. This stops the pilot’s head from over-flexing backwards. The other fix is to adjust the software within the seat sequencer to reduce the parachute loads. A switch will be provided that lighter-weight pilots will set before flying, that provides a slightly longer delay before the parachute opens. This delay—measured in milliseconds—allows the seat and its drogue parachute to slow slightly. An MB engineer told AIN that the sequencer and wiring loom will have to be changed to complete the fix in the F-35 fleet.
Martin Baker has performed 14 tests of the fixes at different speeds with mannequins of various weights. Eight tests remain to be done. The company hopes to have the fixes fully qualified later this year. Lockheed Martin F-35 program manager Jeff Babione said he was “confident that this seat exceeds the requirements as outlined by the U.S. military and the F-35 partner nations.”
Martin Baker is close to saving the 7,500th pilot’s life with its seats. A total of 7,497 successful ejection events have been notified to the company, of which 3,492 were in the U.S. military.