Official statement: The F-35 CAN Supercruise.

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neurotech

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Unread post05 Nov 2012, 18:53

m wrote:Remember I did read an article about the Swedish Saab Viggen. Flying at top speed, run out of fuel in less than five minutes.

Did some calculation. May I am wrong, but got this:

F22
mach 1.82 for 100 nm (185 km )

Mach 1.82 = 2229.5546 kilometers per hour / 1203.86317 nmi per hour

60 min = 3600 sec > 8,3% = 298.8 sec <> 4.98 min

Max. Speed is usually with internal fuel tanks only. Most 3rd Gen fighters would run out of usable fuel in less than 10 minutes of AB Max speed flight. The F-4 may be an exceptions in 3rd Gen fighters.

If you mean 4th gen Saab Gripen then it has a more efficient GE 404 engine although still a relatively low fuel fraction, like most fighters.

Conformal tanks are relatively new feature on "smaller" jets like the F-16, although I suspect it would still reduce top speed having them on the jet.
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Unread post05 Nov 2012, 19:26

m wrote:Remember I did read an article about the Swedish Saab Viggen. Flying at top speed, run out of fuel in less than five minutes.

Did some calculation. May I am wrong, but got this:

F22
mach 1.82 for 100 nm (185 km )

Mach 1.82 = 2229.5546 kilometers per hour / 1203.86317 nmi per hour

60 min = 3600 sec > 8,3% = 298.8 sec <> 4.98 min



Remember the F-22's 100nm figure is listed as part of a combat radius. Therefore the supersonic range is 200nm. We also don't know how fast the F-22 operates when supercruising in these mission profiles. It could be as high as M1.8 but its probably a more economical M1.5 but at a higher altitude (the F-22 as with most jets reach top speeds in the mid to high 30s)

There's too many unknowns with the F-35 quote. We don't know it's exact impact on fuel burn so we don't know how much range is sacrificed for that 150nm dash. We also don't know at what altitudes it can fly supersonic without the blower. This is important because it can directly affect fuel burn as well as the geometry of an engagement. Personally I'd be surprised if the F-35 can supercruise at the same altitudes as the F-22 which would imply a lower specific range. It's still a nice capability to have.
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Unread post05 Nov 2012, 20:33

neurotech wrote:
Scorpion82 wrote:There are enough aircraft out there capable of pulling 9 g with a combat load. There's nothing special about this per se. The question to ask what that combat load includes and what's the g envelope?

Source for that? :D

F/A-18 - 7.5G Limit - Except F-18 (aka Swiss Hornet) is cleared to 9G envelope A/A only.
F-16 is < 7.5G Max with A/G loadout.

F-15 is cleared to 9.0G Max with A/G loadout. ~ 250 jets in US Service.
The F-22 is also cleared to 9.0G with A/G loadout. 180 jets in Service.

The F-22 & F-35 without external stores can still have a combat load-out internally for A/G deployment. A 4th Gen fighter without external stores is basically an airshow jet. Has any A/G combat mission been flown in a F-16 without wing stores?

Edit: 220 F-15E Strike Eagles as well. The 250 F-15s are referenced above are F-15C/D Eagle's most of which are 9G rated. All F-15A/Bs are now retired from USAF/ANG service.


Dude combat isn't automatically AG and the "9 G with AG loadout" is rather questionable for ANY type!
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Unread post05 Nov 2012, 20:57

Scorpion82 wrote:Dude combat isn't automatically AG and the "9 G with AG loadout" is rather questionable for ANY type!

A CAP mission is not a 9G profile. When was the last dogfight in a F-16 in actual combat?
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Unread post05 Nov 2012, 21:24

Scorpion82 wrote:the "9 G with AG loadout" is rather questionable for ANY type!

Yeah, I'm also not finding confirmation for that figure; seems a bit of a stretch. The actual g-limits for various loadouts must be classified, though it's possible that they simply don't know yet.
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Unread post05 Nov 2012, 21:46

1st503rdsgt wrote:
Scorpion82 wrote:the "9 G with AG loadout" is rather questionable for ANY type!

Yeah, I'm also not finding confirmation for that figure; seems a bit of a stretch. The actual g-limits for various loadouts must be classified, though it's possible that they simply don't know yet.

The F-15E would be 9G with usable A/G loadout, but I don't have the F-15E documents for confirmation. The F-22 is 9G rated with weapons(missiles) loaded, but could be limited by internal rack limits.
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Unread post05 Nov 2012, 21:51

Some clues here (best to read entire article).

F-35 Air Combat Skills Analyzed Aviation Week & Space Technology Mar 5, 2009 By Andy Nativi

Original article no longer found here:
http://www.aviationweek.com/aw/generic/ ... dline=F-35 Air Combat Skills Analyzed

BUT... Go here for it [top of page]: http://rnzaf.proboards.com/index.cgi?bo ... 78&page=19

"...Lockheed Martin says it ran the F-35 through the Pentagon’s TAC Brawler simulation for air combat systems analysis, using what would be the “ideal” air combat configuration, taking the conventional-takeoff-and-landing F-35A, the only model designed to perform full 9g maneuvers.

The aircraft can also reach a 55-deg. angle of attack in trimmed flight, while most fighters, excluding the F/A-18, are limited to 30 deg. The exact performance of the current F-35A configuration — also known as the 240-4 — are classified. But a similar earlier standard (240-3) was credited with a maximum speed of Mach 1.67; acceleration from Mach 0.8 to Mach 1.2 at 30,000 ft. in 61 sec.; a top turning speed of 370 kt. at 9g and 15,000 ft.; and a sustained turn capability of 4.95g at Mach 0.8 and 15,000 ft. Moreover, an aircraft with those performance figures would carry two beyond-visual-range AIM-120 Advanced Medium-Range Air-to-Air Missiles (Amraams) in the internal weapons bay...."
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Unread post05 Nov 2012, 22:12

Two missiles in the bays = AMRAAMs
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Unread post05 Nov 2012, 22:36

1st503rdsgt wrote:
Scorpion82 wrote:the "9 G with AG loadout" is rather questionable for ANY type!

Yeah, I'm also not finding confirmation for that figure; seems a bit of a stretch. The actual g-limits for various loadouts must be classified, though it's possible that they simply don't know yet.


That sort of data is going to be in the airframe's Dash-One. I'm looking at a 1-F-4E-1 from 1979 right now, and the G limits on most AG stores are +5.0G/-1.0G, with the exception of AGM-65, which is +6.0G/-3.0G. A2A stores approach airframe limits, and the 'Winder is +6.5G/-3.0G.
I'm truly not sure which of these are inherent limitations of the store, which are structural-related, and which involve the suspension system, but it's fairly safe to say that modern A2A stores have higher G-tolerances than an AIM-7E, for instance.
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Unread post05 Nov 2012, 22:38

spazsinbad wrote:"...Lockheed Martin says it ran the F-35 through the Pentagon’s TAC Brawler simulation for air combat systems analysis, using what would be the “ideal” air combat configuration, taking the conventional-takeoff-and-landing F-35A, the only model designed to perform full 9g maneuvers.

The aircraft can also reach a 55-deg. angle of attack in trimmed flight, while most fighters, excluding the F/A-18, are limited to 30 deg. The exact performance of the current F-35A configuration — also known as the 240-4 — are classified. But a similar earlier standard (240-3) was credited with a maximum speed of Mach 1.67; acceleration from Mach 0.8 to Mach 1.2 at 30,000 ft. in 61 sec.; a top turning speed of 370 kt. at 9g and 15,000 ft.; and a sustained turn capability of 4.95g at Mach 0.8 and 15,000 ft. Moreover, an aircraft with those performance figures would carry two beyond-visual-range AIM-120 Advanced Medium-Range Air-to-Air Missiles (Amraams) in the internal weapons bay...."

Just two? :? The piece is still a bit sparse on definitive details (and old). I guess we'll have to leave the question of g-loading to the fanboys until better information is available
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Unread post05 Nov 2012, 22:44

Spoken by a true NAF YOB. :D
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Unread post05 Nov 2012, 23:05

spazsinbad wrote:Spoken by a true NAF YOB. :D

Ya lost me...
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Unread post06 Nov 2012, 00:30

spazsinbad wrote:... But a similar earlier standard (240-3) was credited with a maximum speed of Mach 1.67;
acceleration from Mach 0.8 to Mach 1.2 at 30,000 ft. in 61 sec.;
a top turning speed of 370 kt. at 9g and 15,000 ft.;
and a sustained turn capability of 4.95g at Mach 0.8 and 15,000 ft.
Moreover, [b]an aircraft with those performance figures would carry two beyond-visual-range AIM-120 Advanced Medium-Range Air-to-Air Missiles (Amraams) in the internal weapons bay...."


These sound not as good as F-16C with 2 missiles + half fuel, as mentioned here:
http://www.f-16.net/f-16_forum_viewtopic-t-1804.html
F-16 has better max speed, acceleration, sustained turn capability.
"370 kt. at 9g and 15,000 ft." This I take as instantaneous turn capability.
F-35A sounds more comparable to F-18C.

Image
F-16 sustained turn capability

Sure F-35A has more "half-fuel" and equipments than 16/18. But
Nevertheless, the F-35 may have notable weaknesses for pure air-to-air combat. For one, it is not designed to conduct engagements in a high-speed, high-altitude, sustained turning environment.
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Unread post06 Nov 2012, 00:53

http://onlineslangdictionary.com/meanin ... ion-of/naf NAF a backwards FAN

http://www.thefreedictionary.com/YOB YOB a backwards BOY

NAF YOB = a backwards FAN BOY. Defs of NAF & YOB may vary according to taste.
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Unread post06 Nov 2012, 00:55

That was a very strangely constructed statement. Not only does the "without fuel-gulping afterburner" allow two possible meanings (either "without any afterburner", or "with afterburner at a low setting that doesn't gulp fuel like full afterburner would", but also, while we can infer that the range they gave was the maximum, it doesn't actually say "up to" or anything like that, so it could just be an example, not the maximum.
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