The F-35’s Martin-Baker Ejection Seat

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SpudmanWP

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Unread post08 Jan 2016, 23:46

This restriction affects how many current F-35 pilots?

Oh that's right... NONE.
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borg

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Unread post12 Jan 2016, 00:02

SpudmanWP wrote:This restriction affects how many current F-35 pilots?

Oh that's right... NONE.


That is a bold statement.
Care to back it up?
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Unread post12 Jan 2016, 00:21

At the time (Nov 1, 2015) of the following link there was one pilot:

http://www.hilltoptimes.com/content/pen ... on-problem

I remember a follow-on article stating that even through LM had hand-made a lighter helmet to allow that pilot (a man btw) to fly without an increase in risk, that pilot decided to pursue a different pilot carrier in the service. I'll try and find it and I am sure someone will have it handy.

----UPDATE--------

Found it
The one US Air Force pilot that was deemed to light to fly received his own specially modified 2.13kg helmet, but a more production-representative light helmet is in the works. That pilot has since changed his career field.


https://www.flightglobal.com/news/artic ... io-418063/
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Unread post12 Jan 2016, 00:54

Thanks 'SWP' we had some of those links here and here on this thread at the time also - for the 'borg':

viewtopic.php?f=60&t=27447&p=306710&hilit=career#p306710
& other:
viewtopic.php?f=60&t=27447&p=306700&hilit=career#p306700
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Unread post15 Jan 2016, 22:43

JPO recognizes the optics, changes course:

JPO Accelerates Timeline for F-35 Ejection Seat Fix
Lara Seligman 3:32 p.m. EST January 15, 2016

"WASHINGTON – The Pentagon has accelerated its projected timeline to implement a series of fixes to safety issues with the F-35 Joint Strike Fighter’s ejection seat, Defense News has learned.

The US Air Force told Defense News last week that the three planned solutions to recent problems with the jet’s escape system would not be fully implemented until early 2018. However, the Joint Program Office, which oversees all three service variants of the F-35, said this week the government and industry team is working hard to accelerate that schedule.

The Pentagon now estimates the services will be able to implement the three parts of the complete solution in October 2017, JPO spokesman Joe DellaVedova told Defense News in a Jan. 15 email. At that time, the services will re-evaluate whether to lift weight restrictions on lightweight F-35 pilots, he said...."

http://www.defensenews.com/story/defens ... /78845102/
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Unread post15 Jan 2016, 23:24

This is the STORY of a lifetime for LARA and she is going to milk it for all it is worth. What has changed in 'maus92' excerpts in one week? USA summer is in October? or SHOCKA is it good news? Something for LARA to scribble about. OR an opportunity for 'maus92' to be ....? "JPO recognizes the optics, changes course:" Damned if they do - Damned if they don't.

viewtopic.php?f=60&t=27447&p=313179&hilit=Lara#p313179 Quote below:
F-35 Ejection Seat Fix Delayed to 2018; Pilot Restrictions Continue
By Lara Seligman | Jan 8 2016 | Defense News

"WASHINGTON — The US Air Force won’t lift weight restrictions on F-35 pilots until 2018 — at the earliest — as more testing needs to be done to address safety issues with the jet’s ejection seat, Defense News has learned...."

"Testing of the seat, built by UK company Martin-Baker, last August showed an “elevated” risk of injury for F-35 pilots weighing under 165 pounds, and an “unacceptable” risk for those under 136 pounds, according to the Air Force."

"The Joint Program Office told Defense News in October that all three fixes would be fully implemented by summer 2017, allowing the services to look at lifting the weight restrictions. But in a Jan. 8 email, the Air Force acknowledged that the date had been pushed back, to early 2018 at the earliest...."

"Part of the delay is the increased testing required for the head support panel, and mating it with the lightweight switch, Jeter wrote in a follow-up email. Once all three fixes are implemented, the Air Force will begin to “relook” at lifting the weight restriction, she said...."

http://www.defensenews.com/story/defens ... /78519892/
RAN FAA A4G Skyhawk 1970s: https://www.faaaa.asn.au/spazsinbad-a4g/ AND https://www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/
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KamenRiderBlade

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Unread post16 Jan 2016, 09:28

So an easy fix is for skinny and lightweight pilots to gain some weight by eating more =D
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Unread post18 Jan 2016, 17:07

F-35 Escape System Update Statement
16 Jan 2016 JPO

"The F-35 program is still in its System Development and Demonstration phase and the aircraft’s safe escape design continues to develop and improve. All ejections from any fighter aircraft are risky and place extreme amounts of stress upon the body. The F-35 escape system was designed to reduce ejection stresses and be able to accommodate the widest range of both aircrew weight and anthropometry (sizes), providing for the safe escape for pilots weighing from 103 to 245 lbs. The designed safe escape range is greater than legacy fighter ejection seats.

During tests to qualify safe escape with a Generation III helmet for lightweight pilots at low speed ejections, data indicated the potential for increased risk of injury under those conditions. On Aug. 27, 2015, the U.S. Services restricted F-35 pilots weighing less than 136 pounds from operating the aircraft. Currently, no F-35 pilots are impacted by this restriction.

All safe escape risks will be reduced and restrictions will be removed after three proposed fixes are complete: installing a switch on the seat for lightweight pilots that will slightly delay parachute deployment and lessen parachute opening forces; designing a lighter helmet; and mounting a head support panel, which is a fabric panel sewn between the parachute risers which will protect the pilot’s head from moving backwards during the parachute opening.

The head support panel and the ejection seat sequencer switch for lighter weight aircrew members are currently being tested as part of the seat qualification which is planned to be completed in October 2016. It is expected that modification kits to retrofit seats currently in operation will be available by November 2016 for F-35 fleet implementation.

Testing will also support the design and certification of a lighter version of the Gen III helmet and allow the program office to begin production of these helmets with initial deliveries scheduled to begin in October 2017. At that time, the services will be able to implement all three parts of the complete solution to lift the weight restriction for pilots less than 136 pounds and mitigate neck injury risks for all F-35 pilots.

The safety of our pilots is paramount and the F-35 Joint Program Office, Lockheed Martin, and Martin Baker continue to work this issue with the U.S. Services and International Partners to reach a solution as quickly as possible."

Source: https://www.f35.com/news/detail/f-35-es ... -statement
RAN FAA A4G Skyhawk 1970s: https://www.faaaa.asn.au/spazsinbad-a4g/ AND https://www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/
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Unread post24 Jan 2016, 00:35

An interesting read re ergonomics.

http://www.thestar.com/news/insight/201 ... rages.html

When U.S. air force discovered the flaw of averages
By discarding the average as their reference standard, the air force initiated a quantum leap in its design philosophy, centred on a new guiding principle: individual fit. Rather than fitting the individual to the system, the military began fitting the system to the individual. In short order, the air force demanded that all cockpits needed to fit pilots whose measurements fell within the 5-per-cent to 95-per-cent range on each dimension.
When airplane manufacturers first heard this new mandate, they balked, insisting it would be too expensive and take years to solve the relevant engineering problems. But the military refused to budge, and then — to everyone’s surprise — aeronautical engineers rather quickly came up with solutions that were both cheap and easy to implement. They designed adjustable seats, technology now standard in all automobiles. They created adjustable foot pedals. They developed adjustable helmet straps and flight suits.
Once these and other design solutions were put into place, pilot performance soared, and the U.S. air force became the most dominant air force on the planet. Soon, every branch of the American military published guides decreeing that equipment should fit a wide range of body sizes, instead of standardized around the average.
Why was the military willing to make such a radical change so quickly? Because changing the system was not an intellectual exercise — it was a practical solution to an urgent problem. When pilots flying faster than the speed of sound were required to perform tough manoeuvres using a complex array of controls, they couldn’t afford to have a gauge just out of view or a switch barely out of reach. In a setting where split-second decisions meant the difference between life and death, pilots were forced to perform in an environment that was already stacked against them.
"When a fifth-generation fighter meets a fourth-generation fighter—the [latter] dies,”
CSAF Gen. Mark Welsh
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Unread post24 Jan 2016, 02:49

What a great article - thanks 'popcorn' - & thank goodness for "the change". This sentence had me chortling: :mrgreen:
"...There was no such thing as an average pilot...."

Junior pilots get used to being classed as 'average' for flying skill assessment - during training and in our Fleet Air Arm anyway. Only after some years the assessment changes to 'above average' - maybe - with experience (and rank perhaps?). No one wants to be 'below average' - there be dragons..... (and ye can fall/sail off the edge of the olde flat worlde). :devil:
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Unread post01 Feb 2016, 21:54

F-35 Joint Strike Fighter (JSF) 2015 [no mention of the LIGHT/HEAVY switch on the Ejection Seat]
Jan 2016 DOT&E

"...Pilot Escape System
• In 2011, the program and Services elected to begin training and flight operations at fielded units with an immature pilot escape system by accepting risks of injury to pilots during ejection. These risks included pilots flying training missions with ejection seats that had not completed full qualification testing and flying overwater without the planned water-activated parachute release system (a system which automatically releases the parachute from the pilot’s harness upon entry into water). Certain risks are greater for lighter weight pilots. Recent testing of the escape system in CY15 showed that the risk of serious injury or death are greater for lighter weight pilots and led to the decision by the Services to restrict pilots weighing less than 136 pounds from flying the F-35.

• Two pilot escape system sled tests occurred in July and August 2015 that resulted in failures of the system to successfully eject a manikin without exceeding neck loads/ stresses on the manikin. These sled tests were needed in order to qualify the new Gen III HMDS for flight release.

- A sled test in July on a 103-pound manikin with a Gen III helmet at 160 knots speed failed for neck injury criteria. The program did not consider this failure to be solely caused by the heavier Gen III helmet, primarily due to similarly poor test results having been observed with Gen II helmet on a 103-pound manikin in tests in 2010.

- The sled test was repeated in August 2015 using a 136-pound manikin with the Gen III helmet at 160 knots. This test also failed for neck injury criteria. Similar sled testing with Gen II helmets in 2010 did not result in exceedance of neck loads for a 136-pound pilot.

• After the latter failure, the program and Services decided to restrict pilots weighing less than 136 pounds from flying any F-35 variant, regardless of helmet type (Gen II or Gen III). Pilots weighing between 136 and 165 pounds are considered at less risk than lighter weight pilots, but at an increased risk (compared to heavier pilots). The level of risk was labeled “serious” risk by the Program Office based on the probability of death being 23 percent and the probability of neck extension (which will result in some level of injury) being 100 percent. Currently, the program and the Services have decided to accept the risk to pilots in this weight range, although the basis for the decision to accept these risks is unknown.

• The testing showed that the ejection seat rotates backwards after ejection. This results in the pilot’s neck becoming extended, as the head moves behind the shoulders in a “chin up” position. When the parachute inflates and begins to extract the pilot from the seat (with great force), a “whiplash” action occurs. The rotation of the seat and resulting extension of the neck are greater for lighter weight pilots.

• The Gen III helmet weighs 5.1 pounds, approximately 6 ounces more than the Gen II helmet. The increased weight is primarily due to the larger/heavier night vision camera optics. The program has a weight reduction project ongoing to determine if approximately 5 ounces can be eliminated in the Gen III helmet by reducing structure and materials without affecting fit or optics. [Removing a day/night visor as appropriate apparently]

• In coordination with the Program Office, the ejection seat contractor funded a proof-of-concept ejection sled test in October to assess the utility of a head support panel (HSP), a fabric mesh behind the pilots head and between the parachute risers, to prevent exceeding neck loads during the ejection sequence for lighter weight pilots. Based on the initial results, the Program Office and Services are considering seat modifications that would include the HSP, but they may take up to a year to verify improvement and install them onto aircraft.

• Additional testing and analysis are also needed to determine the risk of pilots being harmed by the transparency removal system (which shatters the canopy before, and in order for, the seat and pilot to leave the aircraft) during ejections in other than ideal, stable conditions (such as after battle damage or during out-of-control situations).

• The program began delivering F-35 aircraft with a water-activated parachute release system in later deliveries of Lot 6 aircraft in 2015. This system, common in current fighter aircraft, automatically jettisons the parachute when the pilot enters water after ejection and is particularly beneficial if the pilot is incapacitated at this point...."

Source: http://aviationweek.com/site-files/avia ... Report.pdf (361Kb)
RAN FAA A4G Skyhawk 1970s: https://www.faaaa.asn.au/spazsinbad-a4g/ AND https://www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/
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Unread post24 Feb 2016, 04:50

Here's a piece of a story that might be getting some traction over the next few days:

"F-35 tester questions program manager’s claim that ejection seat problems have been fixed.

Exclusive: F-35 Tester At Odds With Program Manager. The director of Pentagon weapons testing is questioning claims by the general in charge of the F-35 fighter jet program that potentially deadly flaws in the plane’s ejection seats have been largely fixed.

The testing official, Michael Gilmore, also confirmed the accuracy of CQ reports last fall disclosing that the F-35’s flawed ejection seat poses a serious risk not just to the lightest weight F-35 pilots, as some Defense Department officials have suggested, but also to pilots weighing up to 200 pounds."

http://www.rollcall.com/news/mccain_wil ... 033-1.html
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Unread post24 Feb 2016, 05:44

FWIW, just wearing JHMCS (which most of us currently do) involves a high likelihood of severe injury in any ejection above 350 knots. That figure used to be 450, and I think it officially still is, but anecdotal evidence of actual mishaps have shown that original number to be optimistic. So I'd argue that most of the CAF as well as USN/USMC equipped tacair are already essentially flying on the equivalent of an over/underweight ejection seat waiver in terms of risk. Just a data point.
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Unread post24 Feb 2016, 07:26

The JHMCS example adds to the point about what you consider to be the standard. If the objective here is to have NO elevated risk, then I wonder if that is attainable at all, and my impression is that pilots are aware of this and comfortable with that reality. They know that every time they take off in any fighter, there is a risk - question is whether it is acceptable and justified given the circumstances. For the testing community, of course, the risk evaluation is very different - but for pilots, this is part of what they do.
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Unread post24 Feb 2016, 07:41

endre wrote:The JHMCS example adds to the point about what you consider to be the standard. If the objective here is to have NO elevated risk, then I wonder if that is attainable at all, and my impression is that pilots are aware of this and comfortable with that reality. They know that every time they take off in any fighter, there is a risk - question is whether it is acceptable and justified given the circumstances. For the testing community, of course, the risk evaluation is very different - but for pilots, this is part of what they do.


100%. While I would agree that the scenario is not ideal, I have never put on a JHMCS and though "man this is dangerous", or had reservations for that matter. Like you mentioned, there is potentially a whole lot of risk in flying, not to mention the risk anytime one pulls the ejection handle regardless of situation. Drogues sometimes don't work……..primary chutes sometimes don't either. Or you can be killed in the initial separation from the aircraft for a whole multitude of reasons. Seats are pretty reliable these days when used within their envelope, but by nature of the situations that often warrant ejection, people are often outside of that envelope. While certainly not the entire "envelope", remember that optimum ejection for NACES or ACES II is still 3k ft AGL minimum in controlled flight, upright (no horizon seeking/correcting seats), climbing if able, and below 250 knots. There aren't that many ejections that occur in that little window of flying, and anything outside of that incurs an inherent increased risk.
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