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No cats and flaps ...... back to F35B?

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No cats and flaps ...... back to F35B?

Old 17th Jun 2012, 09:30
  #1081 (permalink)  
 
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F-35B is where I'd be at, given the choice.
Hmmm Good luck.

5g and [reportedly] no transonic acceleration if a real one trick pony once it's "stealth" is compromised, run away bravely indeed.



Depending who we decide to pick the fight with of course, wouldn't want to expend those expensive [apparently] airframes on a fight we wouldn't win.





Which is the clever part.
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Old 17th Jun 2012, 09:41
  #1082 (permalink)  
 
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Glad Rag,

It is a 7g airframe (yes 'g' available depends on load and height etc) and it certainly does have transonic acceleration capability. You are misinformed I'm afraid.

Stealth is not necessarily a one-trick pony either and, as you say, depends on who you are fighting. Out of a choice of every platform that the west will have in the next 20-30 years, not counting Raptor, I would go to war in F-35 every time.

Ironically, for your statement, F-35C has the worst transonic acceleration of all three variants.
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Old 17th Jun 2012, 10:13
  #1083 (permalink)  
 
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It does two tricks: press-ups and it's Klingon cloaking device.

"Request radar vectors"

"Sorry, Mate. Can't see you.

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Old 17th Jun 2012, 10:19
  #1084 (permalink)  
 
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Engines - the development contract was awarded in November 1996 - they choice of the F-35 over the Boeing X-32 was made as you say in 2001 but they'd already been working on it for 6 years
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Old 17th Jun 2012, 11:14
  #1085 (permalink)  
 
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@ICBM

Yes, you may well be correct that I am misinformed, if you would care to elucidate further that would indeed be of benefit to this "thread".

Would you care to also correct the notion that the performance specification of the various AC marks has been recently revised to give a more realistic view of the aircraft's real world performance.

all the best

gr.

#1082 refers
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Old 17th Jun 2012, 11:19
  #1086 (permalink)  
 
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Originally Posted by ICBM View Post
Out of a choice of every platform that the west will have in the next 20-30 years, not counting Raptor, I would go to war in F-35 every time.
But if you gave pilots a choice I doubt a single one would opt for the 'B' voluntarily.

Ironically, for your statement, F-35C has the worst transonic acceleration of all three variants.
Yes, but....
The C should be the version with the best turn rates of all three. Especially at high altitudes. It has a pretty low wing loading and span loading and a quite moderate sweep. Despite being limited at 7,5g it should have excellent STR and ITR. I expect it to be a good rate and an excellent radius fighter.
At lower altitudes it should be a quite capable low speed performer with relatively little energy bleed in turns thus mitigating the probably less than stellar transonic acceleration in straight and level flight.

I expect the 'A' to have acceptable but not terribly good turn rates, due to 9g capability and relatively high wing loading best turn performance being at rather high speeds (probably even higher than F-16). Fits at least to USAF 'speed is life' paradigm. Will bleed energy significantly in hard turns.
The 'B' combines worst of both worlds: Even higher wing loading than the 'A' (starfighter like wing loading ) and lowest g limit of all three being detrimental in high speed energy fight. Neither rate nor radius fighter.
I see virtually no part in the envelope where I expect it to be competiive against a capable oppenent wrt kinematic performance.

I still have difficulties to understand why not a medium size wing (between 'A' and 'C' size) with a little more sweep to improve acceleration has been chosen for the conventional main version (aka the 'A').
I'm afraid that is part of the price ithe F-35 pays for the modular approach to implement a conventional and a carrier borne version with the same basic wing structure.
For my personal tatse maybe a bit too much compromise.

Last edited by henra; 17th Jun 2012 at 11:22.
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Old 17th Jun 2012, 11:46
  #1087 (permalink)  
 
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Originally Posted by Courtney Mil
It does two tricks: press-ups and it's Klingon cloaking device.

"Request radar vectors"

"Sorry, Mate. Can't see you.
Ouch, ouch and mega ouch!! It really hurts when I laugh and that remark appeals to my sense of humour. I accept it is tongue in cheek and made to make folks smile... Mission accomplished.
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Old 17th Jun 2012, 12:25
  #1088 (permalink)  
 
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The 'B' combines worst of both worlds: Even higher wing loading than the 'A' (starfighter like wing loading ) and lowest g limit of all three being detrimental in high speed energy fight. Neither rate nor radius fighter.
So perhaps the best bet will be to fly as low as possible and going like the clappers in a straight line whilst utilising the front Hemisphere "stealf" to maximum advantage, monitoring all the sensor inputs to "thread the eye of the needle".

A bit like a Buck Rogers version of one of these then?






#1082 refers...
YES I'm waiting to see if anyone else picks up on the similarity of "the deal"


Last edited by glad rag; 17th Jun 2012 at 12:25.
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Old 17th Jun 2012, 14:21
  #1089 (permalink)  
 
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Oh, and as for Kandahar's runway length, there are non-STOVL types out there that could work from the minimum operating strip (MOS) using Pneumatic Arresting Gear (ie. cables) to land and their vast amount of SEP to get airborne. For example, a Super Hornet can get off unassisted on ~400m and then use the arrestor gear for any aborted take offs in the overrun.
There was no arrestor gear there at the time and while the Super Hornet is a massively capable jet, it would struggle to get airborne in that distance with weapons, a full fuel load and at that altitude.

Last edited by Justanopinion; 17th Jun 2012 at 14:22.
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Old 17th Jun 2012, 15:03
  #1090 (permalink)  
 
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Yes, you may well be correct that I am misinformed, if you would care to elucidate further that would indeed be of benefit to this "thread".
Perhaps you would like to direct your assertion to the Integrated Test Force at Pax River and ask the question 'can the -B only pull 5g and does it also fail to accelerate transonically?' Then you will have elucidated everything you need to on that subject. From my perspective I can tell you that your statement in incorrect, however I did caveat it that if you load the jet up enough, and fly high enough, you will get to a point where you will only be able to pull 5g due to Ps and induced drag which brings me on to.....

The C should be the version with the best turn rates of all three. Especially at high altitudes. It has a pretty low wing loading and span loading and a quite moderate sweep. Despite being limited at 7,5g it should have excellent STR and ITR. I expect it to be a good rate and an excellent radius fighter.
At lower altitudes it should be a quite capable low speed performer with relatively little energy bleed in turns thus mitigating the probably less than stellar transonic acceleration in straight and level flight.

I expect the 'A' to have acceptable but not terribly good turn rates, due to 9g capability and relatively high wing loading best turn performance being at rather high speeds (probably even higher than F-16). Fits at least to USAF 'speed is life' paradigm. Will bleed energy significantly in hard turns.
The 'B' combines worst of both worlds: Even higher wing loading than the 'A' (starfighter like wing loading ) and lowest g limit of all three being detrimental in high speed energy fight. Neither rate nor radius fighter.
I see virtually no part in the envelope where I expect it to be competiive against a capable oppenent wrt kinematic performance.
This aircraft isn't a high-g, high SEP dogfighter - I say again, this isn't a high-g, high SEP dogfighter. It was never touted as such, wasn't designed as such, wasn't required as such and won't end up as such. You want that then get LM to re-open the production line and make the F-22 (Air Supremacy Fighter) carrier capable, somehow finding the inordinate amount of money and American 'will to sell' along the way. Additionally, the huge quantity of internal fuel that -C carries (with the same sized donk as -B and -A) means, simply, that yes it's ITR will be fantastic however at mid-high fuel weights it will quickly bleed energy and the STR will be inferior. Light-weight is a different matter.

It does two tricks: press-ups and it's Klingon cloaking device.

"Request radar vectors"

"Sorry, Mate. Can't see you.
That is priceless!
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Old 17th Jun 2012, 15:26
  #1091 (permalink)  
 
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This aircraft isn't a high-g, high SEP dogfighter - I say again, this isn't a high-g, high SEP dogfighter. It was never touted as such, wasn't designed as such, wasn't required as such and won't end up as such.
Them why are we buying it to defend the billion carriers?

Perhaps you would like to direct your assertion to the Integrated Test Force at Pax River and ask the question 'can the -B only pull 5g and does it also fail to accelerate transonically?' Then you will have elucidated everything you need to on that subject. From my perspective I can tell you that your statement in incorrect, however I did caveat it that if you load the jet up enough, and fly high enough, you will get to a point where you will only be able to pull 5g due to Ps and induced drag which brings me on to.....
So you don't have the information either, is that correct?

Rgds again

gr.

#1082 refers
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Old 17th Jun 2012, 16:13
  #1092 (permalink)  
 
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Originally Posted by ICBM View Post
This aircraft isn't a high-g, high SEP dogfighter - I say again, this isn't a high-g, high SEP dogfighter. It was never touted as such, wasn't designed as such, wasn't required as such and won't end up as such. You want that then get LM to re-open the production line and make the F-22 (Air Supremacy Fighter) carrier capable, somehow finding the inordinate amount of money and American 'will to sell' along the way.
No disagreement here.
Unfortunately apart from USAF the F-35 will have to do these missions as well for a lot of countries. So it is required to be capable at least to some extent in classic air combat. Or you put all your money on stealth and hope that in the next 50 years no one finds a way around that. Good luck with that...

Additionally, the huge quantity of internal fuel that -C carries (with the same sized donk as -B and -A) means, simply, that yes it's ITR will be fantastic however at mid-high fuel weights it will quickly bleed energy and the STR will be inferior. Light-weight is a different matter.
I wouldn't completely underrate the C version.

Just to give some perspective:
Thrust: ~195kN.
Empty Weight: ~15.000 kg (?).
Wing area: 62,02m^2.
=> T/W: ~1,30 (airframe w/o fuel)
wing loading empty: 242kg m^2
span loading empty: 1145 kg/m
wing sweep: 35
internal fuel: 9.100kg

For comparison: Su30:
Thrust: 246kN
Empty weight: ~18.500kg
Wing Area: 63,20 m^2
=> T/W: 1,33 (airframe w/o fuel)
wing loading empty: 293 kg/m^2.
span loading empty: 1258 kg/m
wing sweep: 42
Internal fuel 10185kg

As you see also the SU-30 has a massive fuel capacity (even higher compared to the wing area than F-35C). Undoubdtedly with full internal fuel both take quite a hit wrt performance. But in a comparable configuration the C shouldn't be that far from the undoubtedly very good Air superiority fighter the SU-30 is.
That said a specific problem of the F-35 compared to the SU appears to be zero-lift drag/transonic drag. That seems to be quite high and will negatively impact SEP and thus acceleration, climb and to some extent STR.

The point I'm trying to make is that the C might be closer to other very good A2A fighters in some important key parameters than one might think at first glance. Closer than the other versions at least.

That said, the F-22 is in a league completely of its own and it is a pity they did not make more of these fabulous (albeit EXPENSIVE) birds.

Last edited by henra; 17th Jun 2012 at 16:56.
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Old 17th Jun 2012, 16:13
  #1093 (permalink)  
 
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The take off roll of a Super Hornet at SL/ISA max weight is ~3700ft and ~1500ft at minimum weight - all within the capability of what was at Kandahar at the time. Putting in a temporary arrestor system can be done in a matter of hours.

So, like the previous poster said, the Harrier and/or VSTOL wasn't the only option available...

LJ
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Old 17th Jun 2012, 16:46
  #1094 (permalink)  
 
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Glojo,

Sorry to cause you pain, my friend. Only 50% tongue in cheek, of course. Has an aircraft ever been developed and, maybe, brought into service with this much expert, public scrutiny before? We have to be careful because, as we all know, British military aviation policy is made here.

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Old 17th Jun 2012, 17:51
  #1095 (permalink)  
 
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So, like the previous poster said, the Harrier and/or VSTOL wasn't the only option available...
Why were the F15s and F16s based in Bagram at the time?

Why were the only strike platforms flown out of Kandahar the USMC Harrier and then the UK Harrier?

Why did they wait to put in cables?

Probably because the runway had large chunks missing out of it and was being repaired one half at a time. The Harrier was the only realistic option along with the A10.
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Old 17th Jun 2012, 18:18
  #1096 (permalink)  
 
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GR,

So you don't have the information either, is that correct?
The reason I direct you there is because whether you trust my information or not is irrelevant - you seek an official confirmation over my word and I merely directed you to a place where you might start to ask. I know what the response would be and it wouldn't give you an answer either. They will not give you actual aircraft performance unless your official capacity outwith this forum means you need to know - but, your post (#1092 refers!) tells me you don't because you were/are misinformed. Believe what you want, it's a free country.

Henra,

That said a specific problem of the F-35 compared to the SU appears to be zero-lift drag/transonic drag. That seems to be quite high and will negatively impact SEP and thus acceleration, climb and to some extent STR.
You've hit the nail squarely on the cranium.

Leon,

The take off roll of a Super Hornet at SL/ISA max weight is ~3700ft and ~1500ft at minimum weight - all within the capability of what was at Kandahar at the time. Putting in a temporary arrestor system can be done in a matter of hours.
Available rwy at Kandahar was, very frequently, reduced to 2500' or less for hours and hours at a time. That bit of concrete had more patchwork done to it than you'd care to know about as an aviator. A Super H at Kandahar (3300' elevation and +45C) would have needed way more than 3700' with a decent CAS load out and you'd have to be able to move that arrestor gear to a clear bit of runway to recover when another bit is trashed while you were airborne. Yes, I've flown both..
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Old 17th Jun 2012, 18:33
  #1097 (permalink)  
 
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Non-VSTOL using short strips (MOS), temporary matting and temporary arrestor gear is nothing new. This picture was taken 30 years ago in a little place called the Port Stanley Airport in the Falkland Islands...



Plus, check out the SCL! Stanley Airport is about 3,000ft long and F18E/F has bags more SEP, lift and capability!


Last edited by iRaven; 17th Jun 2012 at 18:36.
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Old 17th Jun 2012, 19:07
  #1098 (permalink)  
 
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Plus, check out the SCL! Stanley Airport is about 3,000ft long and F18E/F has bags more SEP, lift and capability!
The average daily temperature and airfield elevation in the Falklands differ some what in comparison to Kandahar.

Plus this article has a different version of the runway length in the FI's to allow the Phantom to operate from it.

Aviation News >> 1435 Flt Says Goodbye Tornado, Hello Typhoon - Global Aviation Resource

Last edited by lj101; 17th Jun 2012 at 19:28.
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Old 17th Jun 2012, 19:35
  #1099 (permalink)  
 
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iRaven,

Good point, well made.


lj101,

I'm sorry, the idea of altitude and temp, valid though it clearly is to aerodynamics, deliberatly misses/avoids, Raven's point. Go back and re-think.
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Old 17th Jun 2012, 19:55
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With the Falkland Islands retaken this detachment returned home on the 14th July to prepare for deployment to Port Stanley and the ongoing defence of the Island itself. The Phantoms were unable to deploy until October however, with the Port Stanley runway in need of extension by some 2000ft and the installation of several RHAG (rotary hydraulic arrestor gear) units which would provide shorter landing runs and minimise wear to the Phantom's brakes
So a three month delay and a 2000 ft runway extension. Non VSTOL using "short strips" (normal size runway) far from the best solution.

Last edited by Justanopinion; 17th Jun 2012 at 19:57.
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