The F-35’s Martin-Baker Ejection Seat

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spazsinbad

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Unread post20 Oct 2015, 03:04

Seligman keeps on updating the same story - wot keeps on givin' - a cornucopia of speculation until more facts are known I guess - after testin' the 'head retards' for the lightweights etc. But whatever. Go here for UPDATE on the 19th Oct 2015. ("...bow your [weary] head - wait for the richochet..." how appropriate are the 'Sweet Child in Time' vidslomo lyrics?):

http://www.lyricsfreak.com/d/deep+purpl ... 38756.html
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USAF: Expanded Risk of Neck Damage to F-35 Pilots
19 Oct 2015 Lara Seligman

"This article, originally published at noon ET Oct. 14, has been updated to include comment from the Joint Program Office, and an Oct. 16 Air Force statement."

Source: http://www.defensenews.com/story/breaki ... /73922710/
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 post21 Oct 2015, 22:08

Official Confirms 'Serious' Risk to Wide Swath of F-35 Pilots
By John M. Donnelly
Roll Call Staff
Oct. 21, 2015, 1 p.m.

"Most F-35 pilots who have to eject during take-off or landing while wearing the latest helmet face a “serious” danger of major injury or death, a senior Air Force official said in a written response to a CQ query.

In addition to pilots weighing 136 pounds or less, “pilots between 136 and 199 are at a serious level risk” when wearing the heavier helmet, the official said.

The statement represents the first official confirmation that the bulk of F-35 pilots, not just the lightest ones, are at risk of dying from whiplash in certain scenarios in the military’s $159 million warplanes — at least unless and until ejection seat flaws are fixed and the helmet’s weight is cut.

It is a risk military officials say they are willing to accept, mostly on the grounds that ejections are rare events."

http://www.rollcall.com/news/official_c ... one=policy
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Unread post21 Oct 2015, 22:33

Again a 'long running script' at the 'roll call' fcks over me computer so here is all the text for thusly afflicted ones...
Official Confirms 'Serious' Risk to Wide Swath of F-35 Pilots
21 Oct 2015 John M. Donnelly Roll Call Staff

"Most F-35 pilots who have to eject during take-off or landing while wearing the latest helmet face a “serious” danger of major injury or death, a senior Air Force official said in a written response to a CQ query.

In addition to pilots weighing 136 pounds or less, “pilots between 136 and 199 are at a serious level risk” when wearing the heavier helmet, the official said.

The statement represents the first official confirmation that the bulk of F-35 pilots, not just the lightest ones, are at risk of dying from whiplash in certain scenarios in the military’s $159 million warplanes — at least unless and until ejection seat flaws are fixed and the helmet’s weight is cut.

It is a risk military officials say they are willing to accept, mostly on the grounds that ejections are rare events.

The risk assessment for pilots of average weight is the product of two things, the official said. First, in tests, mannequins weighing 103 and 135 pounds with the heavier new helmet on their heads broke their necks. Second, no testing has yet been done on mannequins between 136 and 244 pounds, the official said.

In other words, 14 years into the F-35 program — the next generation fighter for the Air Force, Navy and Marine Corps — officials have yet to fully test how the physics of ejection would affect a significant portion of the pilot population.

“The program office has chosen not to investigate this weight range yet but plans to as part of the qualification testing of any adopted solution,” the official said.

The issue is likely to arise at a House Armed Services subcommittee hearing Wednesday at which the F-35 program manager and the Air Force’s point man on the plane are set to testify.

“When the Air Force found out the F-35 ejector seat could kill pilots under 136 pounds, the first thing it should have done was order tests to find out whether it could also kill pilots in the other weight classes who are flying these aircraft every day,” said Jackie Speier, D-Calif., a member of Armed Services who has become vocal on the F-35 jet.

“It is unbelievable that the F-35 program office would not seek out these tests immediately, in order to find out what kind of risks they continue to run with pilots’ lives," she said. "We need to know what kind of danger these pilots are exposed to and how the Air Force plans to mitigate it — and we need to know now.”

Leaders Don’t Acknowledge Risk to All Pilots
Pilots weighing less than 136 pounds are not even allowed to fly the new fighter jet now. That’s because tests have shown those pilots’ center of gravity lands them in an awkward position when the ejection seat’s parachute is released, causing a 98 percent risk of a major and perhaps fatal neck injury during take-off and landing ejections, which occur at speeds near 160 knots, or about 184 miles per hour, according to officials and internal Pentagon documents.

What’s more, the documents show, pilots weighing between 136 and 165 pounds are also at “serious risk” of fatal injury in the same scenarios — a 23 percent chance of major injury or death — due to the physics of the ejection seat, made by Martin-Baker Aircraft Co. Ltd. of the United Kingdom.

The Air Force secretary and chief of staff were quoted in an Oct. 16 statement on the service’s website acknowledging the ban on the lightest-weight pilots (only one such pilot was reportedly affected).

The statement also confirmed the serious risk to pilots weighing from 136 to 165 pounds, which CQ was first to report.

“Based on the remote probability of an event occurring requiring ejection from the aircraft and pilot weight considerations, the airworthiness authorities recommended and the Air Force has accepted continuation of flight for pilots falling within the 136 to 165 pound range,” the Air Force statement said.

However, the Air Force website statement made no mention of any risk to pilots above 165 pounds.

By comparison, the senior Air Force official responded to a CQ query by saying there is a “serious risk” to pilots who weigh up to 199 pounds when ejecting near take-off or landing while wearing the latest “Generation III” pilot helmet. That helmet weighs about 5.1 pounds, [approx. half a pound] more than its predecessors, because it has new and heavier night-vision sensors.

The statement was the first official word supporting information about risks to pilots up to 200 pounds that CQ first reported in articles last week.

Defense Department officials are working hard to reduce the helmet’s weight by about a half-pound. They say those few ounces have a considerable effect on the head of a pilot ejecting at least a dozen times the force of gravity.

Officials are also jerry-rigging [excuse me?!] the ejection seat to reduce the risk to pilots.

Source: http://www.rollcall.com/news/official_c ... one=policy
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 post22 Oct 2015, 00:20

Oh really? Another anonymous "official" being quoted as an authority on the matter, and uses docs that are a couple months old before all the analytical homework was complete.

Maybe someone can find the transcript on what the PEO and MajGen Harrigian (CSAF's F-35 Integration lead) said on the matter in live testimony before the Congress today?

Written SFTR here -- http://docs.house.gov/meetings/AS/AS25/ ... 151021.pdf See page 17 of the doc and note this quote under the "Safe Escape" paragraph --

"The only issue we currently have with the system effects only lightweight pilots (those less than 136 pounds)."
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Unread post22 Oct 2015, 00:32

Thanks 'QS' for the headsup and here is a quote from page six then pages 17-18:
WRITTEN TESTIMONY FOR THE HOUSE ARMED SERVICES COMMITTEE SUBCOMMITTEE ON TACTICAL AIR AND LAND FORCES UNITED STATES HOUSE OF REPRESENTATIVES
SUBJECT: F-35 Lightning II Program Update WITNESS STATEMENT OF:
21 Oct 2015 Lieutenant General Christopher C. Bogdan, USAF; Program Executive Officer, F-35

"...6. Flight Gear not Comfortable or Practical.
F-35 pilot flight equipment (PFE) is integrated with the ejection seat arm restraint system, which limits mobility. The JPO shares this concern and is actively looking for alternatives to include alternate flight gear. With the help of the Aeromedical community, the JPO is pursuing the implementation of an improved capability for in-flight relief without pilots having to unbuckle the seat restraint harness.

7. Seat Configuration. The design of the F-35 is optimized for 21st century warfare long-range see, shoot, kill tactics rather than close-in dogfighting. No change to the rear visibility of the jet will be possible without reducing the one thing that makes the F-35 so survivable – stealth. The pilot community is currently developing tactics and CONOPS to deal with this visibility limitation and should not detract from its survivability or mission accomplishment...."
&
"... • Safe Escape:
The F-35 escape system was designed to provide safe escape for the widest range of both aircrew weight (103 to 245 pounds) and anthropometry (sizes), well beyond current legacy fighters. The only issue we currently have with the system effects only lightweight pilots (those less than 136 pounds). There is an increased risk of neck injury to these lightweight pilots during the three phases of the escape sequence: Catapult, Wind Blast, and Parachute Opening. The reason there is an increased risk only for lightweight pilots is because these pilots are assumed to have lower neck strength than heavier pilots and therefore are unable to sustain higher neck loads we are seeing during ejection.

The program is working with our industry partners on three specific improvements that will provide lightweight pilots that same level of protection and safety as all other F-35 pilots. These three improvements are: one, a reduced weight helmet that weighs 6 ounces less than the current helmet that will reduce neck loads during catapult and windblast phases; two, a pilot “weight switch” on the ejection seat that reduces the opening shock of the parachute by slightly delaying the parachute’s opening for lightweight pilots; and three, a head support that will be sewn into the parachute risers that will reduce the rearward head movement of the pilot when the main chute of the ejection seat opens reducing the pilot’s neck loads. The combination of three improvements will provide the needed protection for lightweight pilots...."

Source: http://docs.house.gov/meetings/AS/AS25/ ... 151021.pdf (100Kb)
Last edited by spazsinbad on 22 Oct 2015, 00:38, edited 2 times in total.
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 post22 Oct 2015, 00:33

quicksilver wrote:Oh really? Another anonymous "official" being quoted as an authority on the matter, and uses docs that are a couple months old before all the analytical homework was complete.

Maybe someone can find the transcript on what the PEO and MajGen Harrigian (CSAF's F-35 Integration lead) said on the matter in live testimony before the Congress today?

Written SFTR here -- http://docs.house.gov/meetings/AS/AS25/ ... 151021.pdf See page 17 of the doc and note this quote under the "Safe Escape" paragraph --

"The only issue we currently have with the system effects only lightweight pilots (those less than 136 pounds)."

Thats simply because no tests were conducted on dummies heavier than 136 pounds !
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Unread post22 Oct 2015, 00:57

quicksilver wrote:Oh really? Another anonymous "official" being quoted as an authority on the matter, and uses docs that are a couple months old before all the analytical homework was complete.

Maybe someone can find the transcript on what the PEO and MajGen Harrigian (CSAF's F-35 Integration lead) said on the matter in live testimony before the Congress today?

Written SFTR here -- http://docs.house.gov/meetings/AS/AS25/ ... 151021.pdf See page 17 of the doc and note this quote under the "Safe Escape" paragraph --

"The only issue we currently have with the system effects only lightweight pilots (those less than 136 pounds)."


The video is in the Program updates thread ;)
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Unread post22 Oct 2015, 02:11

oldiaf wrote:
quicksilver wrote:Oh really? Another anonymous "official" being quoted as an authority on the matter, and uses docs that are a couple months old before all the analytical homework was complete.

Maybe someone can find the transcript on what the PEO and MajGen Harrigian (CSAF's F-35 Integration lead) said on the matter in live testimony before the Congress today?

Written SFTR here -- http://docs.house.gov/meetings/AS/AS25/ ... 151021.pdf See page 17 of the doc and note this quote under the "Safe Escape" paragraph --

"The only issue we currently have with the system effects only lightweight pilots (those less than 136 pounds)."

Thats simply because no tests were conducted on dummies heavier than 136 pounds !


Today at the hearing, Bogdan stated that they had tested the upper end limit at 245lb as well and identified no issues there; I expect that they have models for these sorts of phenomenon and with those 3 data points were able to identify the potential for harm towards pilots heavier than 136lb.
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Unread post22 Oct 2015, 02:43

Expecting peeps to read the original Seligman artickle entirely a lot of relevant to the F-35 bits were left out - so? The amended artickle mentioned top of this page is posted in perpetuity below - why? Just because. [MONDEGREEN]
USAF: Expanded Risk of Neck Damage to F-35 Pilots
19 Oct 2015 Lara Seligman

"This article, originally published at noon ET Oct. 14, has been updated to include comment from the Joint Program Office, and an Oct. 16 Air Force statement."


"WASHINGTON — Weeks after Defense News revealed that the military services had restricted lightweight pilots from flying the F-35 joint strike fighter, the US Air Force officially acknowledged an increased risk of neck damage during ejection to middleweight pilots as well.

In a news release issued Oct. 16, the Air Force confirmed a Defense News report that pilots under 136 pounds are currently barred from flying the fifth-generation aircraft, expected to be the backbone of American airpower for decades to come. It also acknowledged an "elevated level of risk" for pilots between 136 and 165 pounds.

"We expect the manufacturer to find and implement a solution," said Air Force Secretary Deborah Lee James in the statement.

Testers this summer discovered an increased risk of neck damage when a lightweight pilot is ejecting from the plane.

The Joint Program Office blamed the phenomenon on the jet's ejection seat, Martin-Baker's US16E. But interviews conducted by Defense News in recent weeks indicate the added weight and bulk of the new F-35 helmet complicates the problem. It is still unclear whether the blame rests squarely with the helmet, or the seat, or somewhere in between.

The JPO is trying to improve safety for lightweight pilots during an ejection by reducing the weight of the new helmet, built by Rockwell Collins and Elbit Systems of America, which is on its third iteration due to repeated technical problems. Rockwell Collins is now on contract to build a Generation III "Light" helmet, David Nieuwsma, company vice president of strategy and business development for government systems, told Defense News.

"All ejections from any fighter aircraft are risky and place extreme amounts of stress upon the body," JPO spokesman Joe DellaVedova told Defense News in a Wednesday email. "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 US Services and International partners to reach a solution as quickly as possible."

During testing this summer with the Gen III helmet, testers discovered increased risk of injury when a lighter pilot ejects at low speeds, a spokesman for the Pentagon's director of operational test and evaluation confirmed to Defense News in a recent email. Testers found the ejection snapped the necks of lighter-weight test mannequins, according to a source with knowledge of the program.

The potentially fatal problem did not occur during previous tests with the slightly lighter Gen II helmets, according to the source.

Until a permanent fix is found, the US military services have grounded pilots weighing less than 136 pounds, Defense News first reported Oct. 1. The restrictions only affect only pilots under this threshold because lightweight individuals generally have lower less neck strength to absorb force, DellaVedova said. The services are not placing any flying restrictions on heavier pilots, he noted.

But the risk does not disappear above 136 pounds, experts stressed. The low-speed ejection problem is worst with the lightest pilots, from 103 to 135 pounds, and gradually lessens as aircrew weight increases. F-35 pilots above that weight could still experience serious and potentially fatal injury during a low-speed ejection.

One solution is designing a lighter helmet, which will weigh about 4.67 pounds, DellaVedova said. The JPO is looking at reducing internal strapping material and removing an external visor to reduce weight and bulk. A preliminary design review on the improved helmet is scheduled for December, with full implementation planned by summer 2017.

However, DellaVedova stressed that helmet weight was not a factor in the Aug. 27 decision to ground lightweight pilots.

“That was an ejection seat issue discovered during the parachute opening phase and was not related to the differences between the Gen II and Gen III helmets,” DellaVedova said.

But the JPO may not be able to find an easy solution, one expert warned.

The Physics of Ejection
The sequence of an ejection is basically the same across different seat designs, according to a subject matter expert in crew escape systems. After the windscreen canopy is breached, the seat and pilot are launched upward via a rail system at a jarring rate of at least 12-14Gs. The acceleration force is greater for a lightweight person, and can be as much as 18Gs. Back and neck injuries can occur at this point if the pilot is not in the correct position, with his or her head directly centered on the spine.

Once the pilot and seat reach the top of the rails, a rocket under the seat is ignited to lift the pilot-and-seat package free of the plane. At this point, the seat can begin pitching back and forth, a motion much like that of a rocking chair, due to an offset of the rocket thrust with the pilot's center of gravity. The pilot's physical build determines the direction and degree of the pitching motion, according to the expert: a tall, heavy person with a high, forward center of gravity tends to pitch forward, while a short, light person with a low, aft center of gravity tends to pitch backwards.

Wind speed and air drag also aggravate the pitching problem, the expert said. Some seats, like the F-35's, utilize an airbag system stowed in the headrest that deploys on either side of the pilot's head. This is meant to stabilize the pilot's head and neck during ejections. However, the inflated air bags add wind resistance near the top of the seat, causing a lightweight pilot and his or her seat to pitch backwards even further.

These two factors combined cause a potentially dangerous position of the pilot when the main recovery parachute deploys at speeds under 250 mph, the expert said. This can cause a "snapping" of the head and neck backwards, leading to serious and potentially fatal neck injuries.

Ejection seat manufacturers have figured out how to correct the pitching phenomenon at high speeds, before the main parachute deploys. In these conditions, most systems deploy a small drogue chute that slows down the seat, the expert said. But during low-speed ejections, 250 mph or lower, the main parachute must deploy immediately to prevent the pilot crashing into the ground. Drogue chute deployment at that speed would slow deployment of the main chute at a critical moment. Even worse, the two chutes could get entangled.

Some companies have developed pitch-control technologies to solve this problem at low speeds. For instance, UTC Aerospace Systems' ACES II ejection seat — featured in the Air Force A-10s, F-15s, F-16s, F-22s, B-1s and B-2s — and UTC's new ACES 5 seat use what is called a stability package, or "STAPAC" to control pitch motion, according to Jim Patch, senior program manager for ACES 5. STAPAC is a small vernier rocket motor mounted under the seat, which is mechanically redirected by a spinning gyroscope to correct the pitch. In addition, the catapult rocket used on all ACES seats can sense the weight of the pilot and change the ejection thrust to push softer for smaller aircrew and harder for legacy aircrew, Patch said.

Martin-Baker does not appear to have any pitch control at low speeds. The UK-based company has not responded publicly since Defense News broke the story about the dangers to lightweight pilots earlier this month.

A bulkier helmet, like the 5.1-pound Generation III, increases the risk of neck injury during both phases of an ejection, because the forward center of gravity brings the pilot’s head down and strains the neck. However, removing helmet weight will not solve the basic problem of misalignment of the pilot when the main parachute deploys, the expert said.

The Rise of Helmet-Mounted Displays
The advent of modern "helmet-mounted displays," which are rapidly displacing traditional helmets, contribute to an increased risk of neck injuries during ejections. HMDs project information similar to that of head-up displays (HUDs) on an aircrew's visor, and are now commonly used in combat aircraft. These devices often incorporate night-vision systems, cuing systems and more. While HMDs greatly enhance pilots' situational awareness, a March DOD Inspector General report found these systems add weight and bulk compared to a traditional helmet, increasing the risk of neck injury — particularly for lightweight pilots.

The F-35 helmet is large even compared to today's average HMD. All the information pilots need to complete their missions is projected on the helmet's visor, rather than on a traditional HUD. The latest iteration of the helmet, Gen III, is wide from side-to-side and front-to-back, meaning that if a pilot's head is even slightly off center, a significant amount of weight is displaced.

If a pilot's head is off-center during the first phase of ejection, acceleration of the pilot and seat up the rail, serious neck and spine injuries can occur.

Martin-Baker's F-35 seat, it seems, attempts to fix this problem with airbags on either side of the pilot's head — the same airbags that aggravate the pitching phenomenon that occurs in the second phase of the ejection.

Congress recently tried to crack down on ejection seat safety issues due to HMDs. In a report accompanying the fiscal 2015 National Defense Authorization Act, lawmakers wrote that a secretary of the Air Force report on various aspects of the health and safety risks associated with ejection seats "confirmed that, with increased use of helmet-mounted devices, the risks of death or serious injury increases, and increases even more for lighter aircrew." Lawmakers called on the Air Force to review and update a 2010 analysis of alternatives exploring options for a safer ejection system.

In light of the recent revelations about the danger to lightweight pilots, the chairman of the House Armed Services subcommittee on tactical air and land forces, Rep. Mike Turner, R-Ohio, has pledged to hold an oversight hearing on the issue, scheduled for Oct. 21.

The Fix
In addition to designing a lighter helmet, the JPO is looking into two other fixes to the ejection problem, DellaVedova said.

First, the team is working on installing a switch on the seat for lightweight pilots that will delay deployment of the main parachute. The proposed weight switch set will keep the drogue chute attached longer to further reduce the speed of the seat before the main parachute deploys.

In addition, the program will mount a “head support panel,” a fabric panel sewn between the parachute risers that will protect the pilot’s head from moving backwards during the parachute opening. This will prevent the potential hyperextension of the neck and protect the head. Martin-Baker is financing an upcoming ejection seat sled test that will test the head support panel, DellaVedova said.

These two fixes will be introduced when the next upgrade of the ejection seat comes online near the end of 2016.

All three fixes will be fully implemented by summer 2017, DellaVedova noted.

If further testing reveals these proposals are not sufficient to fix the problem, the program may look at replacing the Martin Baker seat altogether, a senior Air Force official told reporters Oct. 15. One alternative option is the ACES 5 seat, the official said.

For now, the Air Force is working through the problem to ensure it does not impact initial operational capability, which is planned for late 2016, according to the official. One male pilot at Eglin Air Force Base was grounded by the restriction, but Air Force leadership has decided to move him to a new career path, the official said.

Meanwhile, although experts expect women to be disproportionately affected, the first and only female F-35 pilot, Lt. Col. Christine Mau, the 33rd Operations Group deputy commander, is still flying the plane."

Source: http://www.defensenews.com/story/breaki ... /73922710/
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 post22 Oct 2015, 06:22

Bogdan: Martin-Baker will cover cost of F-35 ejection seat fix
22 Oct 2015 James Drew

"The F-35 joint programme office expects British firm Martin-Baker to cover the cost modifying the US16E Lightning II ejection seat after it was deemed too dangerous for lightweight pilots.

The seat is meant to safely accommodate pilots weighing 46.7kg (103lbs) to 111.1kg (245lbs), but flying has been restricted to F-35 pilots weighing more than 61.7kg (136lbs) as a stopgap safety measure.

Lt Gen Christopher Bogdan, who heads the F-35 JPO, says two seat-related fixes are being pursued and the government “is not paying a penny for the engineering and implementation of these fixes”.

“The supply chain from Lockheed through BAE Systems through Martin-Baker will bear the cost of fixing this, as they should,” he told reporters after a 21 October congressional heading.

At the hearing, Bogdan said the neck stress for lightweight pilots through the catapult ejection, wind blast and parachute opening phases at low speeds is too high. The chance of a potentially fatal neck injury from an ejection in the low-speed flight envelope is one in 50,000 flight hours for pilots under 61.7kg and the odds for those weighing 61.7kg to 74.8kg (165lbs) is one in 200,000.

“That is a very, very small risk,” Bogdan says. “There are many other airplanes in our inventory that we accept similar risks on.”

To resolve the problem, the programme office intends to install a head support panel between the parachute risers to prevent the pilot’s head from going back too far during ejection. Secondly, a switch will allow lighter pilots to slightly delay parachute deployment, thereby reducing the opening shock.

The programme office has also been working for six months to slim down the third-generation helmet-mounted display, produced by Rockwell Collins and Elbit Systems of America through their VSI joint venture. Today, the helmet weighs 2.31kg (5.1lbs) and the target is 2.18kg (4.8lbs).

The weight of the helmet is a significant cause of neck stress in the last-resort scenario of an ejection. Bogdan says the Gen-3 helmet mounted display has two visors, one for day and one for night flying, but one can be removed and the two can be made interchangeable. [WHAT ABOUT THE TRANSITION FROM DAY/NIGHT & VICE VERSA IN FLIGHT?]

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.

Upwards of 140 aircraft have been delivered to date, and each will require all three modifications before the weight restriction can be lifted.

In another update related to the catastrophic engine failure at Eglin AFB last June, Bogdan says every Pratt & Whitney engine will be retrofitted with new parts by June 2016. About 44% of the fleet has already received the fix. “It was unfortunate, but we’re putting it behind us,” says Bogdan."

Source: https://www.flightglobal.com/news/artic ... io-418063/
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 post22 Oct 2015, 08:48

So, Spaz... how does posting an article (Seilgman) that is two days older than government testimony by both the USAF and the PEO provide anything but more noise to the discussion? Should we believe Seligman and unnamed 'experts' instead of the PEO and Harrigian?

In addtion to the fact that pilots weighing less than 136 lbs cannot fly many other tactical jets (and it has been that way for more than a decade), what seems to be lost is that there are other ejection seat makers wanting a piece of the F-35 business pie who are willing to stir the pot on this to get their nose back under the tent.
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Unread post22 Oct 2015, 09:17

Yep sounds agreeable. I'm just making some points that were lost inadvertently - for example the detail about the 'windbag' MB head cushion effect claimed by that Seligman article. I'm not here nor there on the unnamed experts. If you read what I have commented upon you will see I trust the makers of seats, despite critics of same. Probably there will be no perfect seat but 'good enough' will save plenty of lives - perfection may be obtained later perhaps - or never, we know already the armchair critcis are never going to be satisfied. Everything can be improved but at what cost? It seems to me that the people responsible for signing off on the safety of the MB F-35 seat will be able to make a good case. Will this be in the congressional enquiry?

Life is funny indeed. I could tell a story about myself that makes signing off by potential pilots at the margins of F-35 safety seem weak beer indeed. But my story is not really relevant after all these years. PIlots sign up for risk taking - it is good that they make decisions with the best available information. Trust is really all the pilots have in all the people that design the aircraft - make the aircraft - test the aircraft - maintain the aircraft and their fellow pilots when in some kind of formation or group effort. I'm familiar with the plain speaking of Navy Pilots - in my old world anyway. FARRKKK who would fly at all after hearing their real life stories - all of us - as it turned out.

And yes I think I have already hinted at the alternate seat makers wanting to make a meal of this current seat hiccup. That has been waiting in the wings probably ever since the alternates designed their own version of an F-35 seat - but lost.

And to be clear the original Seligman article was posted on the 14th then she updated it twice (for three posts) the last of which I just referred to instead. That was my mistake. So the last version was posted dated the 19th. Please keep up.

Go to the top of this page of this thread for my error in only pointing to the article that was later posted in full.
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 post22 Oct 2015, 12:14

Can anyone confirms what Lt. Gen. Christopher Bogdan said that the problem is because of the helmet weight not the ejection seat ?
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Unread post22 Oct 2015, 12:51

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Unread post22 Oct 2015, 16:59

Thanks for the exact links 'Dragon029'.

Geez those guys are interested eh. The CHAIRperson cut off Gen. Bogdan explanation - wow. I'm impressed and so was that dead-eyed dickhead. For f'sake - why ask the question if answer is not of interest? Amazing lack of cred on display.
RAN FAA A4G Skyhawk 1970s: https://www.faaaa.asn.au/spazsinbad-a4g/ AND https://www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/
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