The F-35’s Martin-Baker Ejection Seat

[spazsinbad]

Valerie formerly NDIA carries 'sad/bad/martinbaker 'jectionseat ball' now for DefNews rather than Lara moved to AvWeak.

F-35 Program Office at Odds With Air Force Over Ejection Seat
11 Jul 2016 Valerie Insinna

"RAF FAIRFORD, England — The F-35 joint program office (JPO) is at odds with a US Air Force decision to consider a new ejection seat for the aircraft but will reluctantly study the cost and schedule implications of integrating another seat, the program’s top official said Saturday.

At issue is the Martin-Baker US16E ejection seat, which was found last year to cause severe and sometimes fatal neck injuries to lightweight pilots upon ejection. Although Martin-Baker is implementing a number of fixes to their seat, the Air Force also wants the JPO to evaluate how certifying and integrating the United Technologies ACES 5 seat would impact the program.

“I think the Air Force is doing it to mitigate a perceived risk that ultimately the seat may not be as good as they need it to be for the entire envelope of the airplane and the entire envelope of body sizes,” Lt. Gen. Christopher Bogdan, F-35 program executive officer, said at the Royal International Air Tattoo. “We don't necessarily feel that way in the JPO from a technical standpoint.

“We think that the testing we've seen so far in the last few months with the fixes we have in place are going to work,” he continued. “But the Air Force has the right to ask for a new requirement like that on the program, and they have, so we'll walk through that.”

Air Force Lt. Gen. Arnold Bunch, the service’s top uniformed procurement officer, told Defense News last month that he had sent the program office a letter in June requesting information on how integrating the United Technologies seat could impact cost, schedule and other factors such as the aircraft's sustainment or lifecycle.

The JPO has not yet replied but will soon tell the Air Force that it plans to start a new study to assess those potential challenges in detail, Bogdan said. The study would likely conclude around the same time that testing for the Martin-Baker ejection seat wraps up, in November or December.

Even though the modified Martin-Baker seat should be able to meet requirements, it’s reasonable for the Air Force to weigh other options, Pentagon acquisition chief Frank Kendall said Sunday. In fact, this is not the first time the service has looked to replace one program-of-record F-35 technology with another.

“We had a situation with the helmet a few years ago where we did put a fair amount of money to develop an alternative helmet, because at that point we thought there was a very significant risk. We thought we would not mature the baseline design,” he said. “I don’t feel the same way about the ejection seat. I’ve been following that and with some design tweaks, modifications, we should be able to solve that problem.”

On the industry side, F-35 manufacturer Lockheed Martin has not yet been told by the program office to begin assessing the new seat, its program manager, Jeff Babione, said last week.

Bogdan stressed that the service has not made a final decision on whether to proceed with integrating the ACES model.

“We personally think that the Martin-Baker seat is going to meet all of the specs. We think it's going to open up the envelope down to the 103-pound pilot as we talked about. When it does that, it will have the greatest range of any seat out there for fighter airplanes, so we think it's probably the right seat for the airplane right now,” he said.

Until those issues are solved, the Air Force has prohibited pilots weighing less than 136 pounds from flying the aircraft — a decree that has sidelined one pilot...." [more blather about manufacturing effects IF a 2nd eject seat ACES it at URL]

Source: http://www.defensenews.com/story/defens ... /86916700/

[wrightwing]

How about setting a minimum weight limit for pilots. That costs nothing.

[spazsinbad]

Weight Limits were set and the seat fix is in apparently - it is all getting to be a storm in a teacup but butterfly wings fluttering cause tornadoes in Kansas according to CHAOS theories - or something like that (100 monkeys typing?).

BTW MB is paying its share of the change cost with the JPO only chipping in a small amount - all is good in bang seat land.

[wrightwing]

Weight Limits were set and the seat fix is in apparently - it is all getting to be a storm in a teacup but butterfly wings fluttering cause tornadoes in Kansas according to CHAOS theories - or something like that (100 monkeys typing?).

BTW MB is paying its share of the change cost with the JPO only chipping in a small amount - all is good in bang seat land.

I meant set the weight limits, based upon the safety requirements of the seat, rather than spending money to change the specifications on the seat. If you weigh 135lbs or less, you get to fly C-130/17/5, KC-135/10, etc.....

[krorvik]

I meant set the weight limits, based upon the safety requirements of the seat, rather than spending money to change the specifications on the seat. If you weigh 135lbs or less, you get to fly C-130/17/5, KC-135/10, etc.....

Works for most americans. Might be a far worse issue in Japan for instance.

[wrightwing]

I meant set the weight limits, based upon the safety requirements of the seat, rather than spending money to change the specifications on the seat. If you weigh 135lbs or less, you get to fly C-130/17/5, KC-135/10, etc.....

Works for most americans. Might be a far worse issue in Japan for instance.

Let them pay for the modified seats.

[popcorn]

Weight Limits were set and the seat fix is in apparently - it is all getting to be a storm in a teacup but butterfly wings fluttering cause tornadoes in Kansas according to CHAOS theories - or something like that (100 monkeys typing?).

BTW MB is paying its share of the change cost with the JPO only chipping in a small amount - all is good in bang seat land.

This... the issue is settled apparently. Pilots with supermodel BMI will be accommodated and MB is eating the bulk of cost so it's all moot.

[smsgtmac]

You know what would be refreshing? If the majority of these stupid ejection seat stories ever bothered to mention that no other seat has ever been designed to accomodate pilots who weighed so little. Can you try that Valerie? Yeah, That'd be greaat. Thaaaaanks.

[spazsinbad]

Martin Baker Has Fix for F-35 Seat Safety Issue
13 Jul 2016 Chris Pocock

"Martin Baker 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....

...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.”

Source: http://www.ainonline.com/aviation-news/ ... fety-issue

[zerion]

Tests on F-35 Ejection Seat Modifications to Conclude

Two equipment modifications designed to make the F-35 Joint Strike Fighter’s ejection seat safe for use by lightweight pilots will wrap up testing by the second week of September, a source with knowledge of ongoing efforts told Military.com.

Air Force officials acknowledged last fall that pilots weighing less than 136 pounds were barred from flying the F-35A over fears that ejection with the plane’s hefty $400,000 helmet, weighing in at more than five pounds, could result in serious neck damage.

Officials with the F-35 Joint Program Office are seeking a lighter helmet that may be introduced early next year, according to FlightGlobal reports, but also moving forward with proposed changes to the Martin-Baker US-16E ejection seat designed to protect pilots’ necks and lessen the impact of ejection.

The two modifications under consideration are a “lightweight crew sequencer switch” that will slow parachute deployment by milliseconds after ejection, and a head support panel between ejection seat risers, Martin-Baker spokesman Richard Johnson told Military.com.

“Both have performed very well in tests,” he said.

Testing on the equipment should be complete around Sept. 9, the source told Military.com. Martin-Baker executives are expected to brief the Joint Program Office and the Air Force as soon as the next week on the results of testing and to discuss a plan to retrofit existing F-35s with the equipment changes. If all goes well, those modifications will be standard in new-production F-35As by 2017.

Gen. Herbert “Hawk” Carlisle, head of Air Combat Command, told reporters at the Pentagon on Aug. 2 that the Air Force was still considering the possibility of swapping out the existing seat with a replacement, but added he was encouraged by early reports on the Martin-Baker fixes.

“I think they’ve made very good progress in solving the challenges that they had,” Carlisle said. “And it appears, at least at first blush, they may have gotten to the full envelope in a representative manner, with some modifications to the seat. I’m awaiting that data. I haven’t seen it all yet. But it looks very good.”

Johnson said Martin-Baker maintains its ejection seat is the right one for the aircraft.

“We’re taking the Air Force’s concerns seriously and we’re certain that following completion of our test that the Martin Baker seat will be more than acceptable,” he said.


http://www.defensetech.org/2016/08/08/t ... /?mobile=1

[SpudmanWP]

Looks like testing is done...

http://aviationweek.com/awindefense/lig ... -completed

Lightweight Tests Of F-35 Ejection Seats Completed

Martin-Baker has completed testing of its F-35 escape system with lightweight dummies, and told a top U.S. Air Force official last month that a fixes designed to mitigate risk to the lightest fighter pilots are performing ...

If you have a sub, you can get more

[bring_it_on]

Didn't J. Michael Gilmore plan on being ejected out to verify?

[spazsinbad]

Someone has projectile vomited EJECTED a whole bunch of words in anticipation that ACES 5 gets a leg up to the F-35. BUT on the other hand - this is a very long post - it does not look likely but they spewed it up anyways - paid by word? This is a long article so I have attempted to remove all the irrelevant stuff about ACES 5 & how precious it all is to somebody.

F-35 Program Office Hopeful to Move Out on Ejection Seat Retrofit Plan This Fall
19 Sep 2016 Valerie Insinna

"WASHINGTON — With just one test to go, the F-35 joint program office is confident that modifications made to the aircraft’s helmet and ejection seat will ultimately fix issues that greatly increase the risk of casualties to lightweight pilots upon being ejected from the plane....

...In an exclusive interview with Defense News, JPO officials said they expect the Air Force will be able to remove all weight restrictions following the final test of the modified escape system later this month. Preliminary data indicates that the upgraded seat and lighter helmet will have removed what the service termed “excessive” and “elevated” risk to light and mid-weight pilots, said Todd Mellon, the joint program office's executive director.

"We're three to four weeks away from having all of the data done so that we can finalize the technical assessment, put that into a risk assessment, and then ultimately make a recommendation," Mellon said Sept. 16. "We expect all of that to come together towards middle or late October. All indications based on the data we've evaluated and the preliminary results through yesterday are favorable."...

...By the end of the month, Martin-Baker and the program office will have conducted 21 sled tests, which gauge the impact of being ejected at different speeds and altitudes. Some testing occurred at Martin-Baker facilities, while other data was collected during service-led events at Holloman Air Force Base, New Mexico.

Eight of those demonstrations employed a 103-pound mannequin, which was used to verify the escape system’s ability to eject the lightest-weight pilots able to operate the plane, said Navy Lt. Cdr. Nick Sinnokrak, the JPO's crew systems lead. At completion, six of the 21 tests will have also included the lightweight helmet. Five demonstrations included all three factors associated with proving the fix: the upgraded ejection seat, a lightweight helmet and a 103-pound dummy.

The final demonstration at the end of the month will use a heavyweight mannequin to test both the upgraded seat and helmet at 550 knot speeds, said Andrew Martin, Martin-Baker's director of business development and marketing....

..."No one will high-five the world more than myself when the final test is complete, which I'm sure will be a success, and the world and the program can move on to focusing on other things,” he said. “But I really don't take the scenario of the Air Force changing the escape system seriously at all. For that to happen, we would be talking about $50 million and a test program that would take three or four years, at best, for an alternative."...

...Upgrading Existing Aircraft
The joint program office laid out a preliminary plan to retrofit the Martin-Baker seats last week during a visit to Lockheed Martin’s Fort Worth, Texas-based facilities, and will be prepared to proceed once the Air Force concurs with the JPO’s recommendation to remove flight restrictions, Mellon said.

“We expect that to happen in October,” he said. “We will have everything ready to begin the retrofit program in October, but we will not begin retrofit without concurrence.”

It will take about two years to complete the entire retrofit process, said Bjorge. “On the seat side, we’re going to target the training bases, because there are currently no lightweight pilots in the airplanes, so the only way to enter the pipeline is through the training pipeline.”

Martin-Baker and the JPO have already done some advance work to allow retrofits to begin quickly after the seat is re-qualified, Bjorge said. The parts needed for the upgrades are scheduled to arrive in November for immediate installation into seats.

Teams of Martin-Baker engineers will be responsible for modifying the seats at the Air Force bases, said Martin, who estimates that each seat will take about four days to complete.

In the beginning stage, the team will complete about 14 seats per month, ramping up to around 28 seats in 2017, Sinnokrak said.

The lightweight helmets will also begin coming off of Rockwell Collins’ production line this November,  but will be limited to six units this year, said Rich Lukasik, the JPO’s helmet mounted display lead integration engineer. Pilots below the 136-pound weight threshold will be the first to obtain the helmets. Full production of the lightweight helmet starts in 2017.

“Once we begin and get the ramp to an appropriate point, the only thing we’ll produce is the lightweight helmets,” Mellon said."

Source: http://www.defensenews.com/articles/f-3 ... -this-fall

[zerion]

Martin-Baker Requalifying F-35 Seat To Accommodate New Helmet

When concerns emerged in late 2015 that a seat designed to save pilots’ lives might suddenly endanger them, it created a crisis for British family-owned ejection-seat manufacturer Martin-Baker. Now, more than a year later, the company has concluded tests for a modification to the seat that will accommodate and keep safe all the pilots who hopefully will never have to use it. The F-35’s US16E seat is a very different one from its predecessors, says Steve Richards, head of the ...

http://aviationweek.com/combat-aircraft ... new-helmet

[bring_it_on]

Martin-Baker Requalifying F-35 Seat To Accommodate New Helmet

When concerns emerged in late 2015 that a seat designed to save pilots’ lives might suddenly endanger them, it created a crisis for British family-owned ejection-seat manufacturer Martin-Baker.
Now, more than a year later, the company has concluded tests for a modification to the seat that will accommodate and keep safe all the pilots who hopefully will never have to use it.

The F-35’s US16E seat is a very different one from its predecessors, says Steve Richards, head of the US16E program at Martin-Baker. Because of the large number of countries expected to adopt the aircraft, the seat had to be designed for a variety of physiological needs.

Seat Stresses
US16E seat designed for operation from -60-600 kt.

First Western ejection seat capable of being ejected automatically

More than 20 ejection tests needed to requalify

It must accommodate males and females of varying height and weight and must be able to jettison them, fully kitted, at speeds of -60-600 kt. and altitudes of 0-50,000 ft., as well as receive electronic signals from the aircraft to eject the pilot automatically should the F-35B model’s vertical-landing lift-fan system fail. The company has had to develop the US16 with the F-35B’s powered lift capabilities in mind. As the F-35 can fly backward, Martin-Baker had to account for that by designing the seat to operate in non-forward flight, accounting for the negative speed value.

More critically, it also had to factor in the new helmets, which are much larger and heavier now because of the new helmet-mounted display model that has replaced the cockpit-mounted head-up display.

“Although we bought affordability, the US16E had to be better than legacy escape systems, have better head-neck loads, more protection and bring lower risk,” says Richards.“It has been like designing a sports car to deal with lots of extremes.”

The company had already completed qualification of the US16E in 2010 with the initial so-called Gen 2 helmet produced by Vision Systems International, but when issues arose with that helmet, the F-35 Joint Program Office (JPO) decided to introduce the Rockwell Collins and Elbit Systems Gen 3 Lite system, which brought with it a number of changes related to weight and the center of gravity.

Because of this, the replacement helmet had to undergo its own set of ejection-seat tests, which began in October 2013.

“We started getting failures, . . . and it got dramatic in July 2015 when we did a low-speed test at 160 kt.,” Richards tells Aviation Week.

Data showed that as the seat pitched back in the moments after ejection, the mannequin experienced what Martin-Baker calls a neck injury criteria exceedance, where loads on the mannequin’s neck posed a potential or real risk of injury. Exceedances were also recorded in higher-speed tests.

“The last time we did a 160-kt. test, years before, we had passed it . . . . The program didn’t expect us to fail it that much,” Richards says.

When news of the failures became public, the U.S. Air Force banned pilots who weighed less than 136 lb. from flying the aircraft. One Air Force pilot was reassigned to a different aircraft type as a result.

“The failure rate at 160 kt. was one that could not be tolerated, . . . and we had to go back at the design of the helmet and the seat,” explains Richards “We could have put in an interim measure to keep that person flying, but we were told to focus on the solution.”

Lockheed Martin and Martin-Baker began working on a fix in the summer of 2015 and began testing the fixes last October. What was expected to be a delta test program turned into a full-blown requalification of the seat, with 22 ejection tests from rocket sleds in Northern Ireland and New Mexico as well as from Martin-Baker’s test aircraft in France.

The lighter helmet led to a center-of-gravity shift. As for the seat itself, the company has adjusted the software in the seat sequencer, which, as its name suggests, sequences the timings of the various ejection processes, including opening the drogue, releasing the seat and deploying the main parachute.

The timing of these processes is based on velocity, air pressure and altitude information taken by sensors on the seat at the time of ejection; look-up tables (a data process technique that replaces computing with indexed information) provide the correct timings for the conditions.

For pilots in the lower weight range, the company has introduced a graduated delay—around 0.45 sec. for the smallest pilot—into parachute deployment. This change is activated via a switch on the seat.

According to Richards, 99% of pilots will have this switch in the standard position, while the low-weight mode will be activated if the pilot weighs less than 150 lb., although the final decision on the threshold weight will be made by the Air Force and Navy.The other modification is the introduction of the head support panel (HSP), a fabric panel at the base of the harness risers that stops the head from moving backward as the seat pitches back.

This works in conjunction with an inflatable head-and-neck device, which works rather like an airbag on a car, with three fingers inflating around the top and either side of the head, holding it in position.

The HSP is most useful in low-speed ejections after the seat’s rocket motor has burned out and the drogue does not have much control authority. The seat pitches back, and the HSP stops the pilot’s head from doing the same.

Richards says the introduction of both the HSP and new sequencer timings has reduced head-neck loads by a factor of six. “We went from a massive exceedance to a magnitude under the requirement,” says Richards. “The wider [JPO] program liked it . . . . It was a cost-effective, low-mass and quick-change fix and didn’t require software or much complex testing.

“But there were a lot of ‘doubting Thomases,’” Richards adds. “They couldn’t believe it was possible through a simple change.”

The new tests have focused on three key anthropometric groups, Case 1, Case 6 and a hybrid Case 2ST, which covers short torsos. The “cases” are based on a U.S. and European database of consumer body measurements, the Civilian American and European Surface Anthropometry Resource Project, or Caesar. Cases 1 and 6 were tested because they encompass the extremes of the seat. Case 1 represents the smallest adult while Case 6 covers the largest-limbed and tallest pilots.. Case 2ST was tested to determine the mass weight at which the seat switch should be engaged.

Manufacturing of the retrofit for the seats began in January 2016; shipping began last November and modifications are getting underway this month.

The retrofit program is expected to take nearly a year. However, one of the biggest challenges, Richards says, will be making the aircraft available to the Martin-Baker teams. When the retrofit work is completed, the Air Force plans to reopen F-35 training to pilots under 136 lb. by December, the Office of the Director of Operational Test and Evaluation noted in its fiscal 2016 report on the F-35’s progress.

The F-35 JPO tells Aviation Week that it has received the escape system data and documentation from industry and will soon release this to the Air Force and Navy for review, as the services own the airworthiness process. Each will provide their assessment of the escape-system upgrades.

“The JPO has been working hand in hand with the airworthiness officials in the Air Force and Navy to develop the escape fixes and to develop the test plan for the fixes,” the JPO said in a statement. “The services have seen draft reports and are encouraged by the results but are holding their final airworthiness and risk assessment until the final reports are provided. The final reports are scheduled to be delivered soon to facilitate the services’ airworthiness and safety analysis processes.”

However, the tests beg the question of whether, if there are further changes to the helmet or if a new HMD is introduced, a new round of costly ejection-seat testing could be required.

“It all depends on what mass and center-of-gravity changes there were,” Richards says. “If it’s a major change, then it is quite a big program, and if there is a Gen 4 or 5, we will need to do some testing if that came up.”

http://aviationweek.com/combat-aircraft ... new-helmet