Mach 2.0 supercruise and 60,000ft altitude!

[avon1944]

> K-9 <
> Officially the figure stands at Mach 1.58 but then that was achieved in <
> 1991 and represents only 80 per cent throttle. <
Remember, this is NOT a linear scale. This is normally the top end of "military power."

> So it seems that the supercruise speed is limited only by air friction <
> heating on the leading edge. <
The heat is NOT on the leading edge! The wing is designed so the hottest part generated by friction is about 20% the way back on top the wing. That is why one of the specs is the ability to travel at Mach 1.5, at 50,000 feet and, at a positive AOA of 25°! This provides all the hot spots caused by friction are covered by the angle at which the F-22 is flying. The results is the F-22 is flying without hot spots being seen by the opponent. The speed of Mach 1.5 means a Slammer fired will have 50% more range and a higher average flight speed than a Slammer fired at 35,000 feet and Mach 0.9!

> Perhaps the higher supercruise speeds can only be reached or sustained <
> at the very highest of altitudes where the air is thinner? <
No actually the F-22 can exceed Mach 1.0 around sea level but I don't think it can supercruise down there. I do know its acceleration is far better than anything flying down on the deck.


> djelfa <
> can we assume a maximum speed of approaching/exceeding Mach 3? <
No, the "BMI" problem. Use Google or Dogpile search engines and look up "F-22" + "BMI." In reading about the material you will see its strengths and weaknesses.

Adrian

[JaFu]

Avon, the top end of military power is signified by 100% in American military fighters, but I'm not sure about foreign countries. When a fighter puts in full burners it is usually represented by roughly 140% thrust. This is so that pilots know if they move the throttle anywhere beyond 100% they are using their burners. Also, as far as the F-22 reaching speads up to Mach 3, it is not possible for many reasons. Some have been listed, such as heating and the lack of variable inlets because they would compromise stealth. However, one that is usually never mentioned is the fact that the mach wave would be so narrow at that speed that it almost hug the fuselage and pass through the control surfaces and the plane would become unstable/unflyable. This is part of the reason why the SR-71 is so long...the mach wave becomes so narrow that the control surfaces must be a good deal back from the nose of the aircraft in order to not be affected by the wave.

[K-9]

Very informative responses. Thanks for setting me right.

[Giblets]

Thats great, but nothing concorde has not been doing for 30 odd years :P
Compared to other aircraft, official figures:
Raptor: 1.68 Mach
Typhoon: 1.2~1.3 Mach
The Mach 2 supercruise will have been done under 'ideal conditions, i.e with inernal weapons stores only,

According to pilot of F/A-22's declaration, the supercruise of F/A-22 could reach up to Mach 1.68, or about Mach 1.5 with 80% military thrust.

EADS declared that EF-2000 has the potential of 1.5 mach-class supercruise ability. It is said that the maximum military thrust of the EJ-200 engine today could be extended from 13,500 Ib to 15,525 Ib, so if this is introduced it is possible.
The Eurofighters stated supercruise ability is with 6 air-air missiles, whilst many ground stores cannot exceed Supersonic speeds.

[K-9]

'The Mach 2 supercruise will have been done under 'ideal conditions, i.e with inernal weapons stores only,..'

*The F/A-22 would ordinarily carry internal weapons only anyway. It would be quite exceptional for a Raptor to be configured in any other way. And that with 8 AAM's mind you, not 6.


'According to pilot of F/A-22's declaration, the supercruise of F/A-22 could reach up to Mach 1.68, or about Mach 1.5 with 80% military thrust.'

*A supercruise speed of M1.72 is now widely and officially accepted at the normal speed. As I understand it, M2.0 can be reached but it is close to the thermal limit of BMI on the wing.

Key to the F/A-22's abilities apart from stealth are its capacity to operate at much higher speeds for extended periods and also at much higher altitudes and to be fully manoeuverable at those higher speeds and altitudes. Thus as the pilot in the article above states, he can fly 'easily at 60,000 ft.' In another place a different Raptor pilot recounted how he performed a split S at 53,000 and Mach 1.98 (with afterburner I hasten to add). He also managed to fire an AMRAAM at 40,000ft while pulling a 7g turn. Some sources now say that the maximum height ceiling for the Raptor is up to 70,000ft. This is roughly twice the normal operating altitude of other fighter aircraft. There is no possibility of an Su35 engaging a Raptor in a dogfight at 60,000ft.

[airplane]

Truth of the matter, pretty much summing up what some of you guys already said; The f-22 raptor is known as the next best fighter out there, in terms of air dominance. The fact is, wheather some of you guys think that the F-22 Raptor is just an airplane, or its the best airplane in the world isnt really what counts. If you stop and think about it, its not the airplane itself, but the pilot inside that aircraft. My point is, you cant just say an f-22 raptor will do the job in war, when you dont consider the pilot. Although, it helps that the plane is very powerful, etc... that doesnt mean that in a future war, it wont matter if its an A-10, F-16, F-15 or F-22, it could be shot out of the air by a SAM or another plane. You cant just neglect these properties. Tell me what you think.

[bradusa_2003]

just like to add a few things firs of all for robban75 the modern fighters that you mention would come out on top of the F-22 were never developed to compete with it the Euro fighter,rafale,grippen were all developed to compete with the f-35 (jsf) and one on one wouldnt touch the f-22 in anything speed,tech.,or stealth. The radars on the f-22 even admittedly by japan are a generation ahead of what they have in their new f-2 fighters and even the Sukhio design company said their most advanced su-37 was close but not tops over the f-22. Dont get me wrong I like all the planes you mentioned and they are good fighters they just arent in the same class as the f-22. K-8 and giblets those are very good responses, I would like to know where you guys find this stuff so I can increase my knowledge I will be the first one to admit the tech stuff on fighters throws me off but I would like to increase my knowledge of it, if you dont mind sharing. Airplane you are also right the pilot has to be well trained also or an airplane is just a big target to hit that and I will be the first to admit that the russians have some pretty good tech on their SAM's and other missles I believe its the RA73 air to air missle of theirs thats really good so I agree with you on that one. It would be nice to know the top speed with after burners I have also heard its over mach 3 but I would guess it will be some time before it will be declassified the true speed the f-15 wasnt reveled until after the first gulf war in 1991 and it wasnt even common knowledge we had an f-15e until during the war so now we can only speculate on its top speed. If the ceiling for the raptor is at 70,000 ft and I have heard that also then it will likely be able to out fly any enemy aircraft it will face in the near future by anyone.