This article was originally published at 3:18 p.m. EDT October 22, 2015. 

WASHINGTON -- Despite concerns over the safety of lightweight pilots flying the F-35, the vast majority of pilots do not face excessive risk of neck damage during an ejection, the chief of the Pentagon's Joint Program Office (JPO) argued in front of Congress this week.

In response to questioning from Rep. Jackie Speier, D-CA, ranking member of the House Armed Services Committee's Subcommittee on Oversight and Investigations, JPO chief Lt. Gen. Christopher C. Bogdan said there is no elevated risk of injury for F-35 pilots "in the heart" of the weight envelope during an ejection.

"We have done the risk analysis on the test points that we have had on the ejection seat, and what we have found is the only area where we have a problem today is with the lightweight pilot below 136 pounds," Bogdan said during an Oct. 21 hearing of the House Armed Services Committee's Subcommittee on Tactical Air and Land Forces. "But the areas that we have tested indicate that, in the heart of the envelope, for the heart of the pilot population, there is not any increased risk of injury at all."

Bogdan's remarks appear to conflict with a recent Air Force statement that acknowledged an "elevated level of risk" for pilots between 136 and 165 pounds. The statement noted that the risk of critical injury during an ejection is higher for the F-35 seat than legacy fighter-ejection seats.

"While the probability of an ejection in this slow speed regime remains very low, estimated at one in 100,000 flight hours, the risk of a critical injury in that circumstance is currently higher than legacy fighter ejection seats," according to the Oct. 16 statement. "The Air Force has accepted risk of similar magnitude in previous ejection seats."

Based on the remote probability of an ejection, the airworthiness authorities recommended — and the Air Force accepted — allowing pilots between 136 and 165 pounds to continue operating the F-35, the statement notes.

That same statement officially announced that Air Force leaders recently decided to restrict pilots weighing less than 136 pounds from flying the plane due to concerns about ejection safety, a decision first reported by Defense News on Oct. 1.

During the hearing, Speier referred to reports that an internal Pentagon assessment found a 23 percent chance of major injury or death for F-35 pilots between 136 and 165 pounds during ejection. Bogdan refuted those reports before the panel.

"Ma'am, that is incorrect. The data that you have came from a reporter who got a copy of an official-use-only internal DOD document that my team put together to assess the risks of a lightweight pilot and a pilot between 136 and 165 pounds. That document should have never been publicly released," Bogdan said, referring to a recent Congressional Quarterly article. He indicated that CQ misinterpreted the document.

Bogdan went on to lay out the probability of neck injury for F-35 pilots in different weight classes. A pilot who weighs less than 136 pounds has a one in 50,000 chance of neck injury from an ejection, whereas one between 136 and 165 pounds has a one in 200,000 chance of incurring the same damage, he told the House panel.

But after the hearing, Bogdan told a group of reporters that these figures account for the low probability that a pilot will have to eject at all and that they don't reflect the likelihood of injury in the event of an ejection.

In the event of an ejection, that 23 percent chance of injury does exist, Bogdan said.

"So the 23 percent is when he ejects, but the probability of that [pilot ejecting] is one in 200,000," Bogdan said, adding that the latter figure  "is no different than the risk that we see in legacy airplanes today."

Bogdan told the panel that the JPO has tested the ejection seat at low speeds using lightweight mannequins (136 pounds and under) and with heavyweight pilots above 245 pounds. But the program has not tested the seat using a middleweight mannequin, representing most pilots, between 135 and 245 pounds. The JPO is planning tests in that weight envelope down the road, Bogdan said.

The Air Force expects the manufacturer of the ejection seat, UK company Martin-Baker, to find and implement a solution, Secretary of the Air Force Deborah Lee James said in the Oct. 16 statement. The F-35 seat is designed to accommodate the full range of pilots between 103 and 245 pounds.

The JPO, Martin-Baker and aircraft maker Lockheed Martin are working on three fixes to the ejection problem: designing a lighter helmet, installing a switch for lightweight pilots that will delay deployment of the main parachute and mounting a "head support panel" between the parachute risers that will protect the pilot's head from moving backwards during parachute opening.

All three fixes will be fully implemented by summer 2017, the JPO has said.

Twitter: @laraseligman

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