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

SpazSinbad 29th Mar 2013 21:43

'EasyStreet' my quote does not suggest 'supercruise' but 'above Mach 1 at min. A/B setting'. If the exact numbers are out there I'll attempt to find them - one day. The definition of 'supercruise' seems to vary a lot but the quote does not imply 'supercruise' at all.

ORAC 29th Mar 2013 21:52


My old Tornado F3 cruised at M0.99 in dry in 1991.
The Lightning cruised in cold power at M1.3 in the 1960s......

JSFfan 29th Mar 2013 22:16

Depends what speed you are calling 'cruise', LM is M1.5 plus isn't it?
the f-35 is a 750 kt limited to M1.6, I'll let the experts do the alt and speed conversions, but I work it out to be M1.6 in the low 20k ft and at 35k ft the AB will be well backed off

When asked, Lt. Col. Hank "Hog" Griffiths is also quoted as saying the f-35a will do M1.25 in dry.
and
http://www.airforce-magazine.com/Mag...112fighter.pdf
The F-35, while not technically a “supercruising” aircraft, can maintain
Mach 1.2 for a dash of 150 miles without using fuel-gulping afterburners.
“Mach 1.2 is a good speed for you, according to the pilots,” O’Bryan said

The high speed also allows the F-35 to impart more energy to a weapon such as a bomb or missile, meaning the aircraft will be able to “throw” such munitions farther than they could go on their own energy alone."

that's M1.2 dry with with bombs and missiles, no 4.5 gen can match that

















Easy Street 29th Mar 2013 22:39


The definition of 'supercruise' seems to vary a lot
Au contraire, I think it's universally understood to mean 'able to sustain supersonic level flight without reheat'.


Lt. Col. Hank "Hog" Griffiths is also quoted as saying the f-35a will do M1.25 in dry.
No he isn't. He is saying that it can get up to M1.25 in reheat. When you cancel reheat, you are (for a moment) doing M1.25 in dry power. By your rationale, a Tornado F3 can do M2.0 in dry power!

Arguments about how long it takes to slow to subsonic speed are irrelevant - if you cannot sustain >M1.0 without reheat, you are not supercruising, even if you cover 150 miles during the deceleration.

JSFfan 29th Mar 2013 22:53

do you have a link to what you claim?

"Mach 1.2 for a dash of 150 miles without using fuel-gulping afterburners."

for reference the f-22 is said to have a M1.5 dry for a 100 mile dash

Bastardeux 30th Mar 2013 00:26

I don't think it's ever been touted to have supercruise, and to suddenly make up that it does would be a very bold thing to do...

Easystreet is right, the only definition I've EVER heard, is being able to sustain supersonic without using reheat in level flight. Because Lockheed tries to suggest high subsonic speed or low reheat in supersonic is also supercruise, doesn't make it so.

JSFfan 30th Mar 2013 00:30

supercruise for LM is M1.5+, M1.2 dry isn't classed as supercruise, although the eu would class it as such

WhiteOvies 30th Mar 2013 00:36

Kbrockman: I'd suggest that the first upgrade would be from Pratt & Whitney, giving more thrust or making the F-135 lighter or both. Engine technology hasn't stood still either since the design of the F-135 which takes it core from the older F-22 engine.

This sort of upgrade worked extremely well on the Harrier, and as further weight reduction on the Dave B will be difficult given the lengths already gone to, I see it as the priority.

With the advances in Avionics technology I seem to recall that the GR7 to GR9 upgrade actually lightened the aircraft whilst increasing the capability. Which was handy when the requirement to carry Sniper, a Terma pod and a useful weapon load was essential. Weight growth over the lifetime of an airframe is not a given, but more thrust is always good.

JSFfan 30th Mar 2013 00:44

engine upgrade is slotted for block 6, prior blocks get the engine upgrade at major o/haul

Rhino power 30th Mar 2013 01:04


supercruise for LM is M1.5+
LM saying that is a bit like BOEING trying to redefine what a thermal runaway is in regard to the 787 Flatliner's battery woes, it suits their PR bilge. Supercruise is widely accepted as being the ability to maintain supersonic flight with a useful weapon/fuel load without the use of re-heat. I assume the quote about the F-35 being able to do a 150 mile dash at M1.2 was with an internal weapon load? Typhoon has demonstrated supercruise with a useful external load so your assertion that no current 4.5 gen fighter can match the F-35 may be a little flawed...

-RP:ok:

JSFfan 30th Mar 2013 01:06

yes, I said that eu supercruise isn't M1.5+
the phoon with with 2 x 2,000lb bombs, missiles and fuel for the same or greater combat radius?

Rhino power 30th Mar 2013 01:25

Can't remember the exact figures, and can't be ar$ed to go trawling through umpteen million web pages to find them but, i think the Tiffie was with an air to air weapon load.

-RP

Courtney Mil 30th Mar 2013 09:09


so technically you're pretty much at very, very min[imum] afterburner while you're cruising," Griffiths said
It doesn't matter how much you dress it up with claims and comparisons to other aircraft (in-service aircraft), that means (as many others have said here) it doesn't supercruise. Yet another of its shortfalls like acceleration time and sustained g. But it seems that we are able to continue to conveniently overlook these performance issues once they are a few weeks old.

JSFfan 30th Mar 2013 09:16

well if you can ignore this, there isn't much to say
"The F-35, while not technically a “supercruising” aircraft, can maintain
Mach 1.2 for a dash of 150 miles without using fuel-gulping afterburners.
“Mach 1.2 is a good speed for you, according to the pilots,” O’Bryan said"

Courtney Mil 30th Mar 2013 09:21

You've said it yourself,


The F-35, while not technically a “supercruising” aircraft
I can't see much doubt there.

JSFfan 30th Mar 2013 09:33

well if M1.5+ is your standard, only the f-22 supercruises

Courtney Mil 30th Mar 2013 09:39

If Lt. Col. Hank "Hog" Griffiths, director of the integrated Joint Strike Fighter test force, says it needs min burner to maintain supersonic, I don't see any argument.

ORAC 30th Mar 2013 09:40


if M1.5+ is your standard
The only person here defining arbitrary standards to try and deny an incontrovertible fact is yourself. When in a hole, stop digging.

JSFfan 30th Mar 2013 09:47

sorry guys, I'm not in a hole..it seems you can't accept that the f-35 goes M1.2 in dry

you have it wrong courtney, he said cruise, not supersonic

Just This Once... 30th Mar 2013 09:49

I have the F-35 performance figures in front of me every day - it does not maintain M1.2 in dry.

Stop arguing with those who fly or have flown in supersonic aircraft.


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