F-35 Cancelled, then what ?
NAB,
Just my thoughts on that concerning F-35B. It doesn't need to worry about missing a cable, so a bolter for that reason isn't going to be an issue. A rejected VL, for whatever reason, would only be realistic with the engine already at high rpm, so not an issue if the engine is working, too late if it isn't. SSL is still jet-borne flight with the engine at high rpm so a rejection is still feasible until touchdown. After touchdown I can only imagine that a total break failure would necessitate a bolter. But I can't answer that one. Too many variables really.
Regardless of all my thinking above, yes, if the brakes fail once the engine is running down to idle and the jet is running along the deck and the sea is getting close, I can see your point. But I don't think it's as big a concern as it might be on a traditional carrier.
Just my thoughts on that concerning F-35B. It doesn't need to worry about missing a cable, so a bolter for that reason isn't going to be an issue. A rejected VL, for whatever reason, would only be realistic with the engine already at high rpm, so not an issue if the engine is working, too late if it isn't. SSL is still jet-borne flight with the engine at high rpm so a rejection is still feasible until touchdown. After touchdown I can only imagine that a total break failure would necessitate a bolter. But I can't answer that one. Too many variables really.
Regardless of all my thinking above, yes, if the brakes fail once the engine is running down to idle and the jet is running along the deck and the sea is getting close, I can see your point. But I don't think it's as big a concern as it might be on a traditional carrier.
Last edited by Courtney Mil; 3rd Jun 2015 at 07:40.
CM
The latter is the issue. Once you've touched down and dumped the rpm, it's all down to the brakes. There is no way back.
Can see it's probably fine if you're in the approach still with power on, but does mean you've got to carry enough fuel for a go-around - part of the bringback?
Still concerns me, but it seems to be being taken very seriously, which is good. Just as a bit of context, ISTR the first murmurings on SRVL were actually back in 2001 ish.
The latter is the issue. Once you've touched down and dumped the rpm, it's all down to the brakes. There is no way back.
Can see it's probably fine if you're in the approach still with power on, but does mean you've got to carry enough fuel for a go-around - part of the bringback?
Still concerns me, but it seems to be being taken very seriously, which is good. Just as a bit of context, ISTR the first murmurings on SRVL were actually back in 2001 ish.
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About brake failure risk, there could always be a barrier rigged when SSL was being undertaken, on the flight deck as there always was on axial decked carriers to stop the cab going onto the sea or other parked ones, just a thought.
That raised a question, if anyone can help. Obviously the choice would depend greatly on circumstances, but would it be better for a B to take a barrier with weapons on or bolt, dump stores, etc and VL if it were able to? Waste the stores or make a (possibly slow speed) engagement? I wonder what the top load strap would do to the doors and stuff or foul the canopy.
I remember in the early days of the Hawk T1 there was a lot of resistance to taking the barrier because on the long canopy, the worry being that the top load strap would prevent crew egress.
I remember in the early days of the Hawk T1 there was a lot of resistance to taking the barrier because on the long canopy, the worry being that the top load strap would prevent crew egress.
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LO,
Answer to your question - same coefficient of friction as the old deck coating - as per specification and tested out to prove it. As long ago as 2004.
Incidentally, much better friction than a runway, but that's due to all that seagoing aviation on rolling wet decks expertise the USN and the USMC have got
Just to clarify - why the question? Didn't you think the team doing this stuff would have thought of it? How did you think the USN and the RN go about getting aircraft to sea? I'm not criticising, just genuinely interested as to why these sort of questions are being asked. However., happy as always to help where I can.
Best Regards to those putting the coatings down,
Engines
Answer to your question - same coefficient of friction as the old deck coating - as per specification and tested out to prove it. As long ago as 2004.
Incidentally, much better friction than a runway, but that's due to all that seagoing aviation on rolling wet decks expertise the USN and the USMC have got
Just to clarify - why the question? Didn't you think the team doing this stuff would have thought of it? How did you think the USN and the RN go about getting aircraft to sea? I'm not criticising, just genuinely interested as to why these sort of questions are being asked. However., happy as always to help where I can.
Best Regards to those putting the coatings down,
Engines
Is the QE class even going to have a barricade/barrier?
As for the US Marines, they may say "CTOL" 90% of the time but I wonder if that is the full picture? Knowing the Marines they may want to practice in STOL (austere strip) mode more often and as perhaps a carry over from the Harrier. I get the F-35 is not like the Harrier in conventional mode, but I wonder if they would really use two quite different modes (CTOL from land, STOVL from the ship). I would think STOL most of the time (partial deflection, lift fan engaged) with similiar approach and pattern speeds would be preferred?
As for the US Marines, they may say "CTOL" 90% of the time but I wonder if that is the full picture? Knowing the Marines they may want to practice in STOL (austere strip) mode more often and as perhaps a carry over from the Harrier. I get the F-35 is not like the Harrier in conventional mode, but I wonder if they would really use two quite different modes (CTOL from land, STOVL from the ship). I would think STOL most of the time (partial deflection, lift fan engaged) with similiar approach and pattern speeds would be preferred?
Last edited by sandiego89; 3rd Jun 2015 at 13:57.
Engines - Because antiskid was a concern Mr Boffin raised some years ago.
SD89 - In the course of a discussion over life-cycle costs a while back, the Marines disputed a CAPE (Pentagon budgeteer) assessment that was based on AV-8B ops (where nearly all operations are STOVL) and argued that only 10 per cent (IIRC) of F-35B ops would be in STOVL mode. See this post:
http://www.pprune.org/military-aviat...ml#post8008227
SD89 - In the course of a discussion over life-cycle costs a while back, the Marines disputed a CAPE (Pentagon budgeteer) assessment that was based on AV-8B ops (where nearly all operations are STOVL) and argued that only 10 per cent (IIRC) of F-35B ops would be in STOVL mode. See this post:
http://www.pprune.org/military-aviat...ml#post8008227
No, the deck coating per se was not a particular concern.
What was a concern was the impact of brake failure on a 20 te cab, moving at 40-50kts relative, on what might yet be a crowded flightdeck with plenty of armed and fuelled cabs. Whether the deck coating was worn or whether there was "lubricating" fluid present on the surface were strictly secondary concerns.
What was a concern was the impact of brake failure on a 20 te cab, moving at 40-50kts relative, on what might yet be a crowded flightdeck with plenty of armed and fuelled cabs. Whether the deck coating was worn or whether there was "lubricating" fluid present on the surface were strictly secondary concerns.
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Barriers and SSL
Engines et al,
As far as I am aware when the F35B goes to sea on a QEC class carrier, it will be the first time ever that in normal operations that an aircraft has been embarked that will normally be expected to do SSLs.
We are all aware that the weight limits for the F35B are tight and that the undercarriage is not as robust as on F35Cs, what some of us are reasonably concerned about is will the F35B be able to SSL on a QEC, as well as take off on the ski jump with a defined weapons and fuel load.
As far as I am aware there is no evidence that an F35B has been shown to land on the area of a QEC deck doing an SSL, loaded or unloaded. The serious maths might have been done about how the F35B will perform off a ski jump but it has as far as I am aware yet to be demonstrated by a test or development aircraft.
By demonstrated here I mean two things, that the airframe, cracks and all, can withstand the loadings of going through these evolutions and that the software solution does not get itself into an inappropriate state when these evolutions are attempted.
The Barriers bit was unless many of us have read the SSL procedure incorrectly, that we understand that the F35B approaches the rear of the carrier with both forward motion lift and vertical lift, when the F35 is over the deck of the carrier and the wheels have touched down, yes with on PoW with help from the Bedford Array, stopping power comes from the brakes, the engines go to idle I am assuming.
If there is a tyre blow out, brake failure, landing gear failure or some other unplanned occurrence, it would seem that the F35B would have the propensity to slide along the deck of the carrier and project itself into the sea, I do not think that it would be reasonable to rely on the ability of the engine to spool up to give enough power to do a vertical take off, having discarded any and all external stores, to give the damaged plane the opportunity to take off again.
It just seemed sensible risk mitigating and indeed not rocket science that a proven method of stopping planes crashing on axial deck RN and USN aircraft carriers was investigated again.
I am sure that being taken by the barrier will cause structural damage to the F35B, let us hope that the damage is not as serious as kerbing a 1966 Mk1 Lotus Europa was, it meant writing it off, the body work was initially bonded to the chassis, saving a rather expensive aircraft and its pilot, would seem a good idea. I am sure that even the MoD would countenance the purchase of kits of spares to repair on-board F35Bs that have simply taken the barrier, far cheaper one hopes than buying a replacement.
Of course I am not suggesting in any way that the F35B is as fragile as a Seafire was at the beginning of its time as a fleet defence fighter, it would be interesting to know how many spitfire props the BPF, Task Force 57 et al got through, that is not for this thread.
I am sure that you can give us all comfort that all these risks have been theoretically mitigated, it would just be nice to know in the real world that these leading edge evolutions can be safely undertaken by normal FAA and RAF pilots, as they will be required to do with possibly not much sea training in a surge.
Philip
As far as I am aware when the F35B goes to sea on a QEC class carrier, it will be the first time ever that in normal operations that an aircraft has been embarked that will normally be expected to do SSLs.
We are all aware that the weight limits for the F35B are tight and that the undercarriage is not as robust as on F35Cs, what some of us are reasonably concerned about is will the F35B be able to SSL on a QEC, as well as take off on the ski jump with a defined weapons and fuel load.
As far as I am aware there is no evidence that an F35B has been shown to land on the area of a QEC deck doing an SSL, loaded or unloaded. The serious maths might have been done about how the F35B will perform off a ski jump but it has as far as I am aware yet to be demonstrated by a test or development aircraft.
By demonstrated here I mean two things, that the airframe, cracks and all, can withstand the loadings of going through these evolutions and that the software solution does not get itself into an inappropriate state when these evolutions are attempted.
The Barriers bit was unless many of us have read the SSL procedure incorrectly, that we understand that the F35B approaches the rear of the carrier with both forward motion lift and vertical lift, when the F35 is over the deck of the carrier and the wheels have touched down, yes with on PoW with help from the Bedford Array, stopping power comes from the brakes, the engines go to idle I am assuming.
If there is a tyre blow out, brake failure, landing gear failure or some other unplanned occurrence, it would seem that the F35B would have the propensity to slide along the deck of the carrier and project itself into the sea, I do not think that it would be reasonable to rely on the ability of the engine to spool up to give enough power to do a vertical take off, having discarded any and all external stores, to give the damaged plane the opportunity to take off again.
It just seemed sensible risk mitigating and indeed not rocket science that a proven method of stopping planes crashing on axial deck RN and USN aircraft carriers was investigated again.
I am sure that being taken by the barrier will cause structural damage to the F35B, let us hope that the damage is not as serious as kerbing a 1966 Mk1 Lotus Europa was, it meant writing it off, the body work was initially bonded to the chassis, saving a rather expensive aircraft and its pilot, would seem a good idea. I am sure that even the MoD would countenance the purchase of kits of spares to repair on-board F35Bs that have simply taken the barrier, far cheaper one hopes than buying a replacement.
Of course I am not suggesting in any way that the F35B is as fragile as a Seafire was at the beginning of its time as a fleet defence fighter, it would be interesting to know how many spitfire props the BPF, Task Force 57 et al got through, that is not for this thread.
I am sure that you can give us all comfort that all these risks have been theoretically mitigated, it would just be nice to know in the real world that these leading edge evolutions can be safely undertaken by normal FAA and RAF pilots, as they will be required to do with possibly not much sea training in a surge.
Philip
Last edited by PhilipG; 3rd Jun 2015 at 16:20. Reason: Typo
Philip,
I have read through your post twice now and have to agree that your questions are good ones that will be massively important. Hopefully there will be some answers and hopefully the final outcome as they go to sea and start doing it for real will be safe and effective.
I have read through your post twice now and have to agree that your questions are good ones that will be massively important. Hopefully there will be some answers and hopefully the final outcome as they go to sea and start doing it for real will be safe and effective.
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The tread that keeps on giving..
As has been intimated earlier, the thorny question of µ has never actually been fully addressed.
It will be VERY illuminating to see how the RN will actually manage deck operations incl rvl etc, from the aspect of µ and F35 flying ops in ALL conditions..
Edited to add that this could be ground breaking stuff for ALL aviation types..
It will be VERY illuminating to see how the RN will actually manage deck operations incl rvl etc, from the aspect of µ and F35 flying ops in ALL conditions..
Edited to add that this could be ground breaking stuff for ALL aviation types..
Last edited by glad rag; 3rd Jun 2015 at 18:15.
Yes, here it is,
Peter WE,
Only if the engine can wind up in time.
29 May 1982
Royal Navy Sea Harrier FRS1 (ZA174) slid off the deck of HMS Invincible into the sea in bad weather, pilot recovered.[12]
Royal Navy Sea Harrier FRS1 (ZA174) slid off the deck of HMS Invincible into the sea in bad weather, pilot recovered.[12]
Only if the engine can wind up in time.
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Unfortunately having no AFD this commits the now sliding aircraft along the length of the flight deck...
Last edited by glad rag; 3rd Jun 2015 at 18:23. Reason: checking online to see basic deck QE layout..