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-   -   F-35 Cancelled, then what ? (https://www.pprune.org/military-aviation/424953-f-35-cancelled-then-what.html)

LowObservable 1st Jul 2013 19:55

LW - Entirely correct, I'm afraid. The problem is that if one end or other of the lift system on the B decides to cease generating Newtons, the airplane emulates a Russian teenage gymnast and turns upside-down in 0.6 seconds.

Test Flying The Joint Strike Fighter

I believe that the auto-eject is armed when the transition button is pressed and that it is activated by aircraft attitude and rate.

ORAC 1st Jul 2013 20:18

Patent courtesy of the Russians and the Forger.

Who also invented the RVL by the way. Look familiar?


SpazSinbad 2nd Jul 2013 08:36

WASP Prepares for NIGHT F-35B Tests Soon
 
Wasp Passes Aviation Certification 02 Jul 2013 By Mass Communication Specialist 3rd Class (SW/AW) J.C.J. Stokes, USS Wasp Public Affairs

"USS WASP, At Sea (NNS) -- Helicopters and AV-8B Harrier jets roared to life on the flight deck of the amphibious assault ship USS Wasp (LHD 1) June 24-27 as crew members went to work qualifying and passing the Afloat Training Group (ATG) Atlantic Aviation Certification (AVCERT) 1.4 Bravo....

...Day and night, AV-8B Harrier jets, MV-22B Ospreys, MH-60S Seahawk and CH-53E Super Stallion helicopters launched and landed on deck working with flight deck personnel and practicing night vision operations using aided and unaided methods.

"During night time flight quarters the flight deck crew and pilots use night vision goggles to safely land on the ship, and since the ship has to dim its lights to avoid blinding the pilots, this is the aided method," said Aviation Boatswain's Mate 1st Class Jesse Seagrave. "The unaided method is landing aircraft without night vision goggles. Performing both methods gets the flight deck crew and pilots comfortable with landing aircraft in any situation."

Sailors below decks worked hard before and during AVCERT including air traffic controllers who went to team trainers in preparation for the assessment and were instrumental in landing aircraft safely.

"Our job for this mission was to control the Harriers to perform different landing approaches aboard Wasp," said Air Traffic Controller 1st Class Nathaniel Alspaugh. "To make sure we were prepared for AVCERT we went to Pensacola, Fl., and the training we received allowed us to simulate controlling aircraft and perform landing approaches on the flight deck during day and night flight quarters. The majority of the Sailors in my division are new and the fact that they were able to complete this evolution with no problems is truly an amazing accomplishment and I am proud of them."

Wasp passed AVCERT with flying colors and is one step closer to Joint Strike Fighter Developmental Testing Phase II schedule to occur later this summer."
The United States Navy (via noodls) / Wasp Passes Aviation Certification

Bastardeux 2nd Jul 2013 09:41

Pentagon Mulls Delay to Lockheed's F-35 Program - WSJ.com


Richard Aboulafia, a defense analyst with the Teal Group, said delaying the F-35 from full production could cover about 30% of the reductions needed in the procurement budget under the mandatory spending reductions.

But analysts agreed short-term savings will come with long-term costs.

"You are going jeopardize the export market and that will keep costs high," said Mr. Aboulafia. "It is not a death spiral, but it is a pain spiral that could really damage the program."

TomJoad 2nd Jul 2013 10:29


Originally Posted by Roland Pulfrew (Post 5887731)
I would contest that. We CAN afford to, it's just our politicians CHOOSE not to. Any nation that can spend £110 BILLION (that is over 2 1/2 times the Defence budget) on the bureaucracy that is the NHS can afford to be a world class player.

The NHS has become the UK's Sacred Cow - no political party dare challenge it for fear of loosing votes. ALL other Govt departments lose out because of the NHS (and International Aid) being ring fenced. What we cannot afford is the NHS. A 10% saving on the NHS budget would go a long way to solving the shortfall in Defence, and a 20% saving would probably fix it.

Wow:ugh: There was me thinking we had a defence capability to defend our way of life, of which the NHS is fairly central. We do not and should never have a defence capability to simply justify itself and maintain our so called position in the world. I think the comments re affordability are absolutely spot on. As difficult and unpalatable as it may be we need to be trimming back our aspirations. We had a good run, and a lot to be proud of, and we will go on to find another role for our talent.

orca 2nd Jul 2013 15:35

I don't think we need to trim back our aspirations old chap, I think we need to hack them to pieces. Delusions will have to do for now.

Lonewolf_50 2nd Jul 2013 15:52

LO, thanks for the answer, which means you fly with your hands in a "ready to eject" position (which might not be on the controls?) or you get increased flail damage on the way out because the aircraft's pitch rate is being busily corrected (in vain) by your monkey skill reflexes and you are out the top (IIRC, that's a 13 G acceleration with modern seats) in a poor ejection posture.

So it goes, I suppose it beats ending up like quite a few of the Harrier A guys who had those flip overs back in the early days of the AV-8 ... :{

Just wear that neck brace for a while ... that helmet is heavy, right? :p

SpazSinbad 2nd Jul 2013 19:18

HMDS II Weight
 
Early HMDS Helmet stats in 2004 in this PDF have the weight at 3.5lbs:

http://www.safeeurope.co.uk/media/3429/simon_smith.pdf [1.3Mb] (page 4)

I'll look for more uptodate info.
_________________________

Ares: A Defense Technology Blog: F-35 VSI non-HUD HMD

".. a four-pound weight budget?..." Bill Sweetman 12 Apr 2007
__________________________

The Aviationist » Farnborough 2012: This is the most advanced flight helmet, ever. The F-35's Helmet Mounted Display System

"...single [composite carbon fiber helmet] helmet that weighs less than 5 lb. including all components...."

http://theaviationist.com/wp-content...07/mg_0085.jpg

http://theaviationist.com/wp-content...07/mg_0085.jpg

LowObservable 2nd Jul 2013 21:23

LW - Just don't be looking down and over the side at your landing spot when something goes kaflooey, or you'll have a nasty crick in your neck.

SpazSinbad 2nd Jul 2013 21:30

F-35B Auto Eject Dial In Sensitivity?
 
Aaaahh the FUD merchants are back.... Fear Uncertainty Doubt. Good strategy. Notwithstanding all military flying particularly is dangerous - hence ejection seats required. Ask anyone who has ejected what they would rather be - dead or injured?

The auto-eject function is linked via the seat to the FCS Flight Control System according to Martin Baker info. Early on I read that the auto eject system had dial in sensitivity but cannot find that info now.
___________________

F-35

“Auto eject system Active on STOVL variant only
&
The seat incorporates an auto eject function for the F-35 STOVL aircraft to be used in the event of lift fan failure. The auto ejection system utilises a signal from the FCS to initiate ejection....”
F-35

"The US16E Ejection Seat provides an unprecedented balanced optimisation between key performance parameters such as safe terrain clearance limits, physiological loading limits, pilot boarding mass and anthropometric accommodation ranges to fully meet the F-35 Escape System requirements. The US16E will be common to all F-35 aircraft variants.

The US16E is the only Qualified Ejection Seat that meets the US Government defined Neck Injury Criteria (NIC) across the pilot accommodation range.

The US16E design is common to all F-35 aircraft variants."

gr4techie 2nd Jul 2013 22:18


“Auto eject system Active on STOVL variant only
&
The seat incorporates an auto eject function for the F-35 STOVL aircraft to be used in the event of lift fan failure. The auto ejection system utilises a signal from the FCS to initiate ejection....”
Thats all well and good, until the system develops an electrical snag and starts banging out pilots when it shouldn't. I could imagine it'll be quite a surprise! One second you are calmly flying along looking at some pretty clouds, the next second without any warning you are doing 13g through the canopy.

Killface 2nd Jul 2013 22:29


LW - Just don't be looking down and over the side at your landing spot when something goes kaflooey, or you'll have a nasty crick in your neck.
SpazSinbad, he knows, he is just trying to be inflammatory.

LowObservable 2nd Jul 2013 23:39

Spaz - Actually, a little FUD in this program would have been no bad thing. Might have kept us out of the current situation, with well over $50 billion down the tubes, 17 years of not working on alternatives or follow-ons, still five or six years (at least) away from the bare-minimum capability that the contractor promised, while nobody knows how far they are going to have to cut force numbers to compensate for operating costs.

A little FUD might have kept people from betting the farm on promises and projections and the magic of simulations and laboratories. Instead, what got us here was HAG - Hubris, Arrogance & Greed.

Rhino power 3rd Jul 2013 01:00

Very succinctly put LO! :ok:

-RP

SpazSinbad 3rd Jul 2013 01:14

HAGgyFUDdyDuddies
 
Plenty of HAGs and FUDdyDuddies on this forum to keep LM on their toes.

Killface 3rd Jul 2013 06:19


Gilmore also notes that the prognostic and health monitoring system, currently, is unable to provide timely detection of combat damage to the F-35B lift-fan system, which “might fail catastrophically before the pilot can react” during transition to vertical landing. Lockheed Martin comments that “in the remote chance of a failure, the pilot would auto-eject.”
So the problem is a system, that can't detect "combat damage" right now, for an aircraft we are always being reminded is years away from a battlefield, for a liftfan which MIGHT fail "before the pilot can react," and yet if it did, there is an auto ejection system in place already? Whats wrong?

ORAC 3rd Jul 2013 08:23

It's an issue not previously revealed; there's no indication of when, or if, it will be corrected; of which software build it will be incorporated into; and of the cost of rectification.

It may be true that the auto-eject system would take the pilot clear, but if it happened over the deck it would still be incredibly dangerous. Would you like to be on deck when when an F-35B did a back flip 50ft up?

Mach Two 3rd Jul 2013 08:32

Your mistake here is the use of the word 'battle'. There are other ways that the lift fan (or any other component) could become damaged. If there's no ready fix for the inability to detect, probably best just to hope it never happens. After all, bits of birds or rubbish kicked up of the ground hardly ever get sucked into large fans.

SpazSinbad 3rd Jul 2013 08:55

'ORAC' said: "It may be true that the auto-eject system would take the pilot clear, but if it happened over the deck it would still be incredibly dangerous. Would you like to be on deck when when an F-35B did a back flip 50ft up?"

I would like to be nowhere near such an event - including ashore - but I take the point that deck crews are much nearer the action during landings (and they enjoy the view BTW). If such a catastrophic event occurs to an F-35B there is nothing that can be done about it - best the pilot ejects as indicated.

Usually deck crew is at minimal numbers in any danger zone, with the 'lollygaggers/goofer' (spectators) in 'vultures row' in a safer environment above the deck.

LowObservable 3rd Jul 2013 11:47

I don't think that anyone can sanely argue that a system with a failure mode that requires auto-eject is some great advance in flight safety.

Also, I can't think of many forms of combat (or other impact) damage that would go from undetectable to immediate departure with a routine mode switch. For instance, if the gear decides not to come down, you have time to cope with it.

This was raised as an issue with the pre-1995 alternative to the shaft-driven fan, Mac/GE's gas driven fan. How would you know that your gas ducting had been punctured until compressor-exit-temperature gas started blowing into the airframe?


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