According to a report released by DefenseNews.com it looks like the F-35 may be much more dangerous for some pilots than others.
The report revealed that lightweight pilots wearing the aircraft's 3rd-generation helmet-mounted display (HMD) may have their necks snapped while ejecting from the aircraft at a slower speed. This has led all branches of the US military flying all variants of the F-35 to restrict pilots weighing less than 136 pounds from flying the aircraft until the problem is fixed. The original requirements for the seat were to accommodate pilots ranging in weight from 103-245 pounds.
According to Joint Program Office spokesman Joe DellaVedova, at least one pilot is affected by this new restriction. DellaVedova also stated that the new Rockwell-Collins Generation 3 HMD, delivered in August, is not related to the problem or the flight restriction, which was announced on August 27. The 3rd generation HMD is heavier than the 2nd generation HMD, however, and any addition helmet weight would be amplified by the forces generated during ejection.
In this video, produced by Martin-Baker, the maker of the F-35's US16E ejection system, you can see at 52 seconds and at 1:03 the stresses put on the neck as the pilots are ejected from the aircraft at around 12-14 Gs.
Despite the fact that this only affects a very small number of pilots, many lawmakers are calling for increased oversight on what has already been a bloated and over-budget aircraft. Many are using this as another opportunity to bring up the cost-ineffectiveness of the Pentagon's rush to field new equipment and technology before it is thoroughly and completely tested. This piles on additional costs as already-produced aircraft must now be updated.
Rep. Mike Turner (R-OH), a member of the House Armed Services committee, says that this issue (and likely many others) will be discussed in an Oct 21 oversight hearing for the F-35.