More delays for the F-35
all eight run-in/rolling tests undertaken...to see if the F-35C CV JSF could catch a wire with the tail hook have failed
I should think that spreadsheets are running hot, to determine whether the price difference between SH and Dave-C would pay for a second set of cats and arrester wires.
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I'm hoping our First Sea Lord might have seen the light on his visit to the Stennis Battle Group and with that in mind, is a Hornet in the hand worth a 'C' in the bush?
Glojo,
"is a Hornet in the hand worth a 'C' in the bush?"
Indeed it is. Actually a F35C may be worth several F18s. I'm sure someone here can tell us how many. You know what I mean.
In my view, F35B = too many moving parts, too many potential points of failure. F35C = wonderful if you REALLY need all that stealth, etc, but no good if it can't catch a wire.
Super Hornet appeals to me more and more every day. I might even rejoin to fly it!!!!
Torque, Nice one!
"is a Hornet in the hand worth a 'C' in the bush?"
Indeed it is. Actually a F35C may be worth several F18s. I'm sure someone here can tell us how many. You know what I mean.
In my view, F35B = too many moving parts, too many potential points of failure. F35C = wonderful if you REALLY need all that stealth, etc, but no good if it can't catch a wire.
Super Hornet appeals to me more and more every day. I might even rejoin to fly it!!!!
Torque, Nice one!
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I've been out of the loop for a while on this one, but with the US defence cuts being implemented, does anyone know if Dave-B will survive? I've never understood the operational point of it, other than to keep the USMC happy.
And however problematic the tailhook saga (no, not *that* Tailhook Saga) is with Dave-C, I'm sure the USN will get it fixed because they're not going to want to run about in the Western Pacific without LO technology - and for them (at least in the manned world) Dave-C is the only game in town.
S41
And however problematic the tailhook saga (no, not *that* Tailhook Saga) is with Dave-C, I'm sure the USN will get it fixed because they're not going to want to run about in the Western Pacific without LO technology - and for them (at least in the manned world) Dave-C is the only game in town.
S41
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And however problematic the tailhook saga (no, not *that* Tailhook Saga) is with Dave-C, I'm sure the USN will get it fixed because they're not going to want to run about in the Western Pacific without LO technology - and for them (at least in the manned world) Dave-C is the only game in town.
Out of curiosity, is the tailhook / undercarriage distance significantly shorter than it was on the F-7U Cutlass:
or F-4D Skyray:
both of which, particularly the Cutlass, had similarly short-couped configurations to the F-35C?
or F-4D Skyray:
both of which, particularly the Cutlass, had similarly short-couped configurations to the F-35C?
Ecce Homo! Loquitur...
Battleland: Vertically Challenged: Marine F-35 Engines’ Long Lead, Much Higher Cost
You may recall a couple of weeks ago when we reported, based on our own crude analysis of a Pentagon contract announcement, that the latest batch of engines for the Marine’s F-35 fighter would cost $129 million apiece, five times the $25 million sticker on the Air Force F-35 motor. The Marines’ higher cost is because its airplane is going to be able to make short take offs and land vertically. The Marine F-35 needs to be able to do this because its amphib aircraft carriers are smaller than the Navy’s (why the U.S. military needs the world’s two largest carrier fleets is a topic for another day).
Unfortunately, that amazing vertical jump in the Marine price tag doesn’t look like an aberration. On Friday, the Pentagon announced how much it is spending to buy so-called “long-lead items” for another batch of F-35 power plants (it’s the first contract in the list). This is stuff that takes awhile to make, so it’s ordered in advance of the actual engine contract:
You may recall a couple of weeks ago when we reported, based on our own crude analysis of a Pentagon contract announcement, that the latest batch of engines for the Marine’s F-35 fighter would cost $129 million apiece, five times the $25 million sticker on the Air Force F-35 motor. The Marines’ higher cost is because its airplane is going to be able to make short take offs and land vertically. The Marine F-35 needs to be able to do this because its amphib aircraft carriers are smaller than the Navy’s (why the U.S. military needs the world’s two largest carrier fleets is a topic for another day).
Unfortunately, that amazing vertical jump in the Marine price tag doesn’t look like an aberration. On Friday, the Pentagon announced how much it is spending to buy so-called “long-lead items” for another batch of F-35 power plants (it’s the first contract in the list). This is stuff that takes awhile to make, so it’s ordered in advance of the actual engine contract:
- Air Force: $3.1 million per engine
- Navy: $5.3 million per engine
- Marines: $14.1 million per engine
BEags,
I wonder if it has more to do with TIME between main gear trampling the cable and the hook trying to catch it. Your vids show the very low approach speeds of the F-7U and the F-4D. So even with a relatively short gear-to-hook-shoe distance, the time is obviously significantly greater.
It also looks like the hooks hang very low on those two types - probably isn't room to put a longer hook on F35C. Some of the traps in those vids may even have been with the jet still airborne, so gear hadn't trampled the wire.
Just a couple of theories. Someone here will probably know better.
Courtney
I wonder if it has more to do with TIME between main gear trampling the cable and the hook trying to catch it. Your vids show the very low approach speeds of the F-7U and the F-4D. So even with a relatively short gear-to-hook-shoe distance, the time is obviously significantly greater.
It also looks like the hooks hang very low on those two types - probably isn't room to put a longer hook on F35C. Some of the traps in those vids may even have been with the jet still airborne, so gear hadn't trampled the wire.
Just a couple of theories. Someone here will probably know better.
Courtney
You're very probably right, Courtney. I understand that it is indeed the effect of the main gear trampling the wire first which has caused the problem, because the cable dynamics are such that it isn't back at the correct deck height before the hook reaches it. As for approach speeds, the F-7U videoclip starts with a number of slow motion clips - see the guy 'running' in the background.
Presumably the F-35C needs a 'stealthy' hook fitting as well - so modification would cost $LOTS?
Yes, the UK will probably be far better off with an F-18E/F/G fleet if F-35C costs and delays keep increasing.
And isn't the F-35 a butt-ugly looking thing? It it looks good..... As witness the unsurpassed F-15C!
Presumably the F-35C needs a 'stealthy' hook fitting as well - so modification would cost $LOTS?
Yes, the UK will probably be far better off with an F-18E/F/G fleet if F-35C costs and delays keep increasing.
And isn't the F-35 a butt-ugly looking thing? It it looks good..... As witness the unsurpassed F-15C!
Further to my last, I've just found this on the "F-35 Cancelled, Then What?" thread. Posted by Engines on 17 Dec 11:
Engines gave a very comprehensive post about the whole hook issue and the problems with repositioning it, etc.
And YES, it's so ugly. Who'd want to be seen flying that?!
Courtney
This is a complex one to fix and test, as the time between the main wheels hitting the wires and the hook engaging them is not fixed and the dynamic behaviour of the wire is complex, depending whether you engage in mid span or off centre.
And YES, it's so ugly. Who'd want to be seen flying that?!
Courtney
You'd hope that the LM design office had access to and NAVAIR read their own publication (Aircraft Carrier Reference Data Manual). Basic rules for hook/wire geometry are in there IIRC....
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Out of curiosity, is the tailhook / undercarriage distance significantly shorter than it was on the F-7U Cutlass: or F-4D Skyray:
in hook down configuration, are hard to find). As for the Crusader. They certainly ironed out the snags with that one.
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Guys,
Further to my last on 17 Dec (Thanks Courtney!),
Having quickly looked at the arresting gear Mil Spec, I can't find a specific gear/hook distance requirement. There are a zillion other parameters there for various angles, clearances, etc., and the F-35C hook, as far as I remember, meets those.
I can confirm that the team designing the hook (which is LO - it retracts under a complex set of covers) were certainly fully aware of all the various specs. They had a couple of goes at getting a hook that did that, and one of the redesigns addressed a problem you can see on the Crusader picture (nice pic) which shows an effect called 'wheelbarrowing', where the hook is too low down on the aircraft. When it engages the wire, the effect is to pull up on the fuselage, lifting the mains off the deck, and leaving the aircraft sitting unstably on its front leg. The first hook design sat it too low, so a redesigned mounting yoke system was then used.
The hook system design was also exhaustively checked by the US Navy NAVAIR engineering and flying specialists before it was approved for manufacture.
THe USN specs are largely empirical and actually reflect the experience gained on aircraft like the F-7U and F-8U. By the way, the Cutlass landings were on a straight deck, and they had up to 12 wires at one stage to make sure they caught a wire - the options weren't too goog if they didn't.
The lesson here (sorry if I sound a bit schoolmasterish) is that getting 'cat and trap' to work with large high performance combat aircraft is really, really difficult. The USN make it look easy because they are damned good at it. It's also risky and takes a high degree of skill to do even when you get the kit right. I wonder whether our lords and masters really understood all that when they went for the C. (John Farley would have plenty to say on this, I'm sure). I'm not saying it's a wrong decision, we just need to get our heads around the reality of it. This thread is really helping to do that.
Best Regards as ever to all those on land and sea and air who are doing the job for real,
Engines
Further to my last on 17 Dec (Thanks Courtney!),
Having quickly looked at the arresting gear Mil Spec, I can't find a specific gear/hook distance requirement. There are a zillion other parameters there for various angles, clearances, etc., and the F-35C hook, as far as I remember, meets those.
I can confirm that the team designing the hook (which is LO - it retracts under a complex set of covers) were certainly fully aware of all the various specs. They had a couple of goes at getting a hook that did that, and one of the redesigns addressed a problem you can see on the Crusader picture (nice pic) which shows an effect called 'wheelbarrowing', where the hook is too low down on the aircraft. When it engages the wire, the effect is to pull up on the fuselage, lifting the mains off the deck, and leaving the aircraft sitting unstably on its front leg. The first hook design sat it too low, so a redesigned mounting yoke system was then used.
The hook system design was also exhaustively checked by the US Navy NAVAIR engineering and flying specialists before it was approved for manufacture.
THe USN specs are largely empirical and actually reflect the experience gained on aircraft like the F-7U and F-8U. By the way, the Cutlass landings were on a straight deck, and they had up to 12 wires at one stage to make sure they caught a wire - the options weren't too goog if they didn't.
The lesson here (sorry if I sound a bit schoolmasterish) is that getting 'cat and trap' to work with large high performance combat aircraft is really, really difficult. The USN make it look easy because they are damned good at it. It's also risky and takes a high degree of skill to do even when you get the kit right. I wonder whether our lords and masters really understood all that when they went for the C. (John Farley would have plenty to say on this, I'm sure). I'm not saying it's a wrong decision, we just need to get our heads around the reality of it. This thread is really helping to do that.
Best Regards as ever to all those on land and sea and air who are doing the job for real,
Engines
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Engines,
Thank you for that post which makes a number of excellent points.
How sad that we have gone from a World leading nation regarding conventional aircraft carriers to a nation that has now lost all that type of experience**.
**Ark Royal de-commissioned in 1978 which was the last conventional carrier.
Thank you for that post which makes a number of excellent points.
How sad that we have gone from a World leading nation regarding conventional aircraft carriers to a nation that has now lost all that type of experience**.
**Ark Royal de-commissioned in 1978 which was the last conventional carrier.
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About the pictures;
That's not a Cutlass but a Skyray in photo number 2.
The Cutlass had also some tailhook problems but because it had a massively
high frontgear and a high AoA when landing combined with a redesigned hook that was considerably further away from the rear LG compared with the F35C
it eventually was able to land on the Carriers.
The F35C's hook is indeed too close to the rear gear, even closer than the
unmanned X-47, but it is not a showstopper in the longrun, a redesigned hook
(the actual catching part) is already being manufactured giving it a higher probability of trapping the wire, also a hook that pivots the other way around
is possible giving automatically a much greater distance without needing a major strenghtening of the frame while making it possible to make it fully covered by RAM plating better integrating it into the plane improving its Stealth characteristics also.
All this will still leave you with a weighty 7.5G plane that is very complicated
to maintain, won't have a lot of the promised features (Helmet, etc...) that made it so much better on paper, with reduced visibility from the cockpit (compared with all of its predecessors like the F16,F15,F18, AMX) which is worse in real dogfights, has a weaker cannon (vs 30mm on the EF) with a longer startup time, a big thirsty 43000lbs engine which is also very loud BTW
I sincerely hope that some of the customers come to their senses, certainly
the British who seem to be too willing to just give up on their ability to design a complete fighter from the ground up themselves.
The EF, contrary to what many people seem to believe, was and still is a very
good fighter which has its fundamentals right, their is also a lot of potential to improve upon it.
Stronger engines (up until 40% more power) and TVC, a potentially top of the line Radar (CAESAR) with a wide field of view, something missing on other AESA'S, and the continuing implementation of new and better systems.
Even the NaVAL Typhoon could have been a good thing, as it is it is already
very resistant against the saline environment and has a very strong frame needing only limited strenghtening (340kg latest assesments) in the frame, the landing gear and the arrestor hook and another 70kg if they would opt for the TVC on the engines.
It wouldn't need catapults to lift of at MTOW, only the originally designed ramp and the arrestor hooks, further decreasing costs for the new CVF's, while having a very high commonality with an already existing fleet of RAF Typhoons.
This would also mean that it can get airborne much faster while at the same time being the absolute top dog in A2A close combat with its TVC engines.
I just cannot understand you guys, have some proud in what you can achieve, don't just buy into the fairytale that LM advocates.
They have a questionable reputation anyway.
Originally the 5th generation(a term invented by their PR department btw) ATF they said the F22 would be
-1)easy to maintain by 1 mechanic and 2 enlisted men (like the SaaB philosophy)
-2)Have a high degree of reliability.
-3)would be fully integrated with all other systems in the USAF (link16 and such)
-4)could supercruise
-5)have a wide field AESA (with sidelobes)
-6)have all round LO layout.
-7)could use the latest weapons at full potential
It failed miserably on the first 3 and is left with an AESA with a narrow field of view while being unable to launch HOBS missiles and with an antiquated processor making future upgrades a challenge to say the least.
They royally F$%""#d us with the F104 and as things stand today, the same is gonna happen with the F35.
By their own admission (original standards of a 5th gen fighter) the F-35 is anything but a 5th generation fighter.
It won't be easy to maintain, it won't supercruise, it will only have limited LO characteristics mainly front views, it will not have the wunderhelmet but just a regular of the shelf model instead.
To top it all of, future upgrades and new weapon integration can only be done by the grace of LM (source code issues for anybody except the British I believe) for what will undoubtedly be a "nice" price.
All things suggest that the original fighter maffia was right all along, not surprising if you realize that they actually had hands on experiece.
That's not a Cutlass but a Skyray in photo number 2.
The Cutlass had also some tailhook problems but because it had a massively
high frontgear and a high AoA when landing combined with a redesigned hook that was considerably further away from the rear LG compared with the F35C
it eventually was able to land on the Carriers.
The F35C's hook is indeed too close to the rear gear, even closer than the
unmanned X-47, but it is not a showstopper in the longrun, a redesigned hook
(the actual catching part) is already being manufactured giving it a higher probability of trapping the wire, also a hook that pivots the other way around
is possible giving automatically a much greater distance without needing a major strenghtening of the frame while making it possible to make it fully covered by RAM plating better integrating it into the plane improving its Stealth characteristics also.
All this will still leave you with a weighty 7.5G plane that is very complicated
to maintain, won't have a lot of the promised features (Helmet, etc...) that made it so much better on paper, with reduced visibility from the cockpit (compared with all of its predecessors like the F16,F15,F18, AMX) which is worse in real dogfights, has a weaker cannon (vs 30mm on the EF) with a longer startup time, a big thirsty 43000lbs engine which is also very loud BTW
I sincerely hope that some of the customers come to their senses, certainly
the British who seem to be too willing to just give up on their ability to design a complete fighter from the ground up themselves.
The EF, contrary to what many people seem to believe, was and still is a very
good fighter which has its fundamentals right, their is also a lot of potential to improve upon it.
Stronger engines (up until 40% more power) and TVC, a potentially top of the line Radar (CAESAR) with a wide field of view, something missing on other AESA'S, and the continuing implementation of new and better systems.
Even the NaVAL Typhoon could have been a good thing, as it is it is already
very resistant against the saline environment and has a very strong frame needing only limited strenghtening (340kg latest assesments) in the frame, the landing gear and the arrestor hook and another 70kg if they would opt for the TVC on the engines.
It wouldn't need catapults to lift of at MTOW, only the originally designed ramp and the arrestor hooks, further decreasing costs for the new CVF's, while having a very high commonality with an already existing fleet of RAF Typhoons.
This would also mean that it can get airborne much faster while at the same time being the absolute top dog in A2A close combat with its TVC engines.
I just cannot understand you guys, have some proud in what you can achieve, don't just buy into the fairytale that LM advocates.
They have a questionable reputation anyway.
Originally the 5th generation(a term invented by their PR department btw) ATF they said the F22 would be
-1)easy to maintain by 1 mechanic and 2 enlisted men (like the SaaB philosophy)
-2)Have a high degree of reliability.
-3)would be fully integrated with all other systems in the USAF (link16 and such)
-4)could supercruise
-5)have a wide field AESA (with sidelobes)
-6)have all round LO layout.
-7)could use the latest weapons at full potential
It failed miserably on the first 3 and is left with an AESA with a narrow field of view while being unable to launch HOBS missiles and with an antiquated processor making future upgrades a challenge to say the least.
They royally F$%""#d us with the F104 and as things stand today, the same is gonna happen with the F35.
By their own admission (original standards of a 5th gen fighter) the F-35 is anything but a 5th generation fighter.
It won't be easy to maintain, it won't supercruise, it will only have limited LO characteristics mainly front views, it will not have the wunderhelmet but just a regular of the shelf model instead.
To top it all of, future upgrades and new weapon integration can only be done by the grace of LM (source code issues for anybody except the British I believe) for what will undoubtedly be a "nice" price.
All things suggest that the original fighter maffia was right all along, not surprising if you realize that they actually had hands on experiece.
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Kbrock,
You are spot on that the Cutlass had severe problems - the extended nose gear was added to achieve reliable launch, the cockpit then had to be raised, and its controllability on approach was always marginal at best. I understand it was called the 'Ensign Killer' due to its poor safety record.
Your comments on the F-35C hook are spot on too - they will fix this, but they are running risks until the optimised hook shape and damper setup are proved.
On the other points you made:
1. The F-35 will get its new helmet, as it has to. With no HUD, the HMD has to work. They have just launched a parallel effort to look at a varient of the UK Typhoon helmet, which is a world beater.
2. Visibility from the cockpit on the A and C is actually extremely good. B only marginally less good.
3. F-35's cannon is a 25mm Gatling vs EF 27mm Mauser revolver with very similar muzzle velocity. The Mauser is the slightly better cannon (it was the original choice but removed after pressure from US companies) but the 25mm is not one I'd call 'weak'.
4. Longer startup time - the aircraft meets its startup time requirements. Yes, big engines take a longer time to get going, though.
5. I agree that it's a real shame that the Uk no longer has the cojones to go on and develop its own fighter aircraft, but proposing the Sea Typhoon as a replacement is not, in my view, an option. Here's why.
6. The 'Naval Typhoon' (not that it actually exists) is not resistant to saline environments. It has strong frame sure enough - for air to air combat, though, as that is what it was designed for. Not deck operations. The EF had a very aggressive weight reduction programme of its own in the late 90s and there is not a spare ounce left over.
7. Because of this, talk of 'only limited strengthening being needed' is about as credible as the LM claims you mentioned. 370kg is a dream, and doesn't match the actual results of doing the same exercise on T-45 or F-35. The problem is that for cat and trap ops, there are all new load paths that just don't exist on a land based aircraft. You need new metal in new places, not beefed up existing.
8. It can not (and I know what I'm talking about here) get off the deck at MTOW without a catapult, unless the definition of MTOW is changed. TVC won't help, and no one answered the question of how the flight controls would work at low launch speeds. (I saw one proposal for a rection control system like the Harrier, but no explanation of where the additional engine thrust was coming from to power it). Adding catapult capability would mean an all new front leg and tons (and I do mean tons) of extra structure to handle the loads.
9. Finally, and here's the crunch, the UK do not want the world's best A2A close combat aircraft (which, by the way, I agree that the EF very probably is) flying off the ships. They want a fully capable strike aircraft with 'day one' signature. That's why the USN are going for F-35C, and that's why we are too.
Best Regards as ever to all those actually doing the job
Engines
You are spot on that the Cutlass had severe problems - the extended nose gear was added to achieve reliable launch, the cockpit then had to be raised, and its controllability on approach was always marginal at best. I understand it was called the 'Ensign Killer' due to its poor safety record.
Your comments on the F-35C hook are spot on too - they will fix this, but they are running risks until the optimised hook shape and damper setup are proved.
On the other points you made:
1. The F-35 will get its new helmet, as it has to. With no HUD, the HMD has to work. They have just launched a parallel effort to look at a varient of the UK Typhoon helmet, which is a world beater.
2. Visibility from the cockpit on the A and C is actually extremely good. B only marginally less good.
3. F-35's cannon is a 25mm Gatling vs EF 27mm Mauser revolver with very similar muzzle velocity. The Mauser is the slightly better cannon (it was the original choice but removed after pressure from US companies) but the 25mm is not one I'd call 'weak'.
4. Longer startup time - the aircraft meets its startup time requirements. Yes, big engines take a longer time to get going, though.
5. I agree that it's a real shame that the Uk no longer has the cojones to go on and develop its own fighter aircraft, but proposing the Sea Typhoon as a replacement is not, in my view, an option. Here's why.
6. The 'Naval Typhoon' (not that it actually exists) is not resistant to saline environments. It has strong frame sure enough - for air to air combat, though, as that is what it was designed for. Not deck operations. The EF had a very aggressive weight reduction programme of its own in the late 90s and there is not a spare ounce left over.
7. Because of this, talk of 'only limited strengthening being needed' is about as credible as the LM claims you mentioned. 370kg is a dream, and doesn't match the actual results of doing the same exercise on T-45 or F-35. The problem is that for cat and trap ops, there are all new load paths that just don't exist on a land based aircraft. You need new metal in new places, not beefed up existing.
8. It can not (and I know what I'm talking about here) get off the deck at MTOW without a catapult, unless the definition of MTOW is changed. TVC won't help, and no one answered the question of how the flight controls would work at low launch speeds. (I saw one proposal for a rection control system like the Harrier, but no explanation of where the additional engine thrust was coming from to power it). Adding catapult capability would mean an all new front leg and tons (and I do mean tons) of extra structure to handle the loads.
9. Finally, and here's the crunch, the UK do not want the world's best A2A close combat aircraft (which, by the way, I agree that the EF very probably is) flying off the ships. They want a fully capable strike aircraft with 'day one' signature. That's why the USN are going for F-35C, and that's why we are too.
Best Regards as ever to all those actually doing the job
Engines