Talk:Supercruise

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[edit] Concorde did supercruise

As our Concorde article points out, Concorde did supercruise, but the engines did have afterburners for accelerating to its superconic cruise speed. Hence I'm going to put it back in the list. --Robert Merkel 02:19, 3 August 2005 (UTC)

If it's ok to include Concorde, what about Tu-144, which also seemed to have the capability? According to the article, "A cruising speed of Mach 1.6 was possible."(when A/Bs OFF) - Marsian / talk 07:04, 3 August 2005 (UTC)
Er... "It was possible to fly at Mach 1.6, but usually it did not. Instead, it always used A/Bs and flied at Mach 2" was the case? Or... - Marsian / talk 07:14, 3 August 2005 (UTC)
Sure. But stick a note that it usually cruised with afterburners. --Robert Merkel 08:33, 3 August 2005 (UTC)
Gotcha, thanks. - Marsian / talk 10:50, 3 August 2005 (UTC)
Thanks for the correction. I had missed the fact that the presence of afterburners and supercruise capability were not exclusive. Maybe a few words about this in the article would avoid future confusion. --Homer Jay 15:58, August 7, 2005 (UTC)

[edit] As a rule of thumb...

All aircraft capable of Mach 2+ speed in level flight at some altitude with afterburners can do Mach 1+ at the same altitude without. Just look at the F-104: Military thrust is 48kN, with AB it's 69kN, i.e. less than 60% more. Theoretically it could do Mach 2.2 with AB. Even if we assume supersonic drag to increase linear with airspeed (it's worse), this will give us > Mach 1.5 without AB. For other aircraft this is not much different. - Alureiter 22:37, 14 December 2005 (UTC)

Wrong. I don't understand the aerodynamics, but it appears the thrust needed to cruise above the speed of sound is dramatically more than you need to cruise below it, so most fighters can't go supersonic without afterburners. As this Air Force press release on the F-22 says
Mushala added that "Its ability to supercruise will allow the F-22 larger patrol areas, and permit the Raptor to enter and exit hostile areas in quick fashion, reducing the time a pilot spends over an enemy’s territory. The capabilities of an F-22 aircraft will be a great benefit to our warfighters."
Virtually all other modern day fighters must use their afterburner either to sustain supersonic flight or to reach initial supersonic speeds.
I'll take the USAF's word for it...--Robert Merkel 23:57, 14 December 2005 (UTC)
I don't understand the aerodynamics, but it appears the thrust needed to cruise above the speed of sound is dramatically more than you need to cruise below it - This is exactly my case, since the thrust with afterburners is not dramatically more than without it. BTW: see also http://www.dcr.net/~stickmak/JOHT/joht12f-104.htm:
Many of the Century Series fighters could supercruise, though most of those just barely. (As a rule of thumb, any plane which can exceed Mach 2 with afterburner can probably exceed Mach 1 without.) Starfighters with the J79-19 engine can - at altitude - maintain about Mach 1.1 in level flight in military power (maximum throttle without afterburner). This isn't surprising when you realize that the J79 engine was vastly improved during the long production lifetime of the F-104, with later versions producing nearly as much thrust without afterburner as early models did with.
This is were I got that rule of thumb from. (But my simple calculations are obviously wrong). Alureiter 00:13, 15 December 2005 (UTC)
I think the rule of thumb is correct, but there's a joker in the pack. For example Concorde used reheat (a/b) to go supersonic, but then supercruised. I read in a book on Concorde that it turns out that Concorde had enough thrust to go supersonic without reheat, but it took ages to push through the hi-drag transonic regime. Since drag is bad, you're just pissing away fuel. Net upshot was, Concorde used more fuel avoiding reheat, than with it, for distance over the ground, so they always used reheat in practice. I bet that many other supersonic planes are the same.WolfKeeper 19:37, 23 January 2007 (UTC)

[edit] Not all aircraft can supercruise like you think.

Basically at this rate you can add the F-16, F/A-18E, and F-15 to the list. Most modern aircraft can go over mach 1 without afterburner in a clean configuration.

However, with the exception of Civilian aircraft, military aircraft should be excluded from the list if they cannot supercruise with full combat capability. The Rafale's supercruise capability is merely a claim not a fact. Hence it should be removed from the list.

Remember, supercruise is typically described as efficient supersonic travel without the use of afterburner. The Eurofighter Typhoon also does not fit into this category as it is never stated that it can supercruise for the majority of its combat radius.

Ex: The F-22A can supercruise efficiently because its engines were designed to do so. The Eurofighter's Eurojet engines are IN FACT in the same class as those used on the F/A-18E.

At this rate, the list will keep getting longer and longer.

This article, like all articles on the latest generation of fighter aircraft, suffers from a severe lack of credible sources. It would be a whole lot easier if you'd cite yours so we can evaluate your claims. Oh, and in the unlikely event you're a defence contractor or work for an air force who has direct knowledge of some of this, could you please go leak away to Jane's or some other publication so we can then cite them rather than making anonymous claims on the Wikipedia? --Robert Merkel 05:36, 11 January 2006 (UTC)
All gas turbines work most efficient at their max rev (=max power) settings, so your claim is bogus. - Alureiter 09:37, 11 January 2006 (UTC)
Your absolutely correct. But the engine's efficiency isnt in question, but the overall performance of the airframe itself. At transonic speed the air passes across the airframe irregularly, some areas at supersonic, and others subsonic, decreasing the overall efficiency in flight. Whereas on the F-22, it can fly at supercruise due to its high dry thrust and clean airframe design, as this was intentional. Skrip00 22:00, 11 January 2006 (UTC)
Again, can you cite a source for this? --Robert Merkel 22:43, 11 January 2006 (UTC)
http://en.wikipedia.org/wiki/Transonic The Eurofighter fits into this category very well with its quoted "supercruise" speeds.Skrip00 23:07, 11 January 2006 (UTC)
It also fits into supersonic. Also: The Eurofighter's engines are much less powerful (just 2x60kN dhry) compared to the F-22. If the Typhoons airframe is so inefficient, why does it still reach Mach 1.3 with external armament but without afterburners? And why does it reach >Mach 2.0 with just 2x90kN "wet" (comapred to F-22's 2x156kN). *sigh* I know from public discussion boards (something wikipedia is NOT!) such attempts to make the F-22A shine more, e.g. some people define supercruising as "cruising without afterburners at Mach 1.x", and x is an arbitrary number choosen so that the F-22A makes it and concurrent models not. But as a matter of fact, as long as we keep "our" reasonable and accepted defintion here, i.e. cruising supersonic at military/dhry thrust/without afterburner, many other aicraft besides F-22A can supercruise. Yepp, even the old Ligthening. - Alureiter 00:00, 12 January 2006 (UTC)
Perhaps we can further define supercruise using the qualifier "efficient". This way we can knock off alot of aircraft that dont truely belong on the list. Or move them into a "disputed" category. Like I said, at this rate we better add the Su-27, F-15C, and F/A-18E onto the list as all these aircraft can theoretically supercruise in a clean configuration. Also, the Eurofighter's numbers are still unreleased.Skrip00 00:08, 12 January 2006 (UTC)

"If the Typhoons airframe is so inefficient, why does it still reach Mach 1.3 with external armament but without afterburners?" - Simple, aircraft engines have come a long way. You can push a 747 to over mach 1 without afterburners if you really wanted to... but it isnt really aerodynamically suited to do it. Skrip00 00:07, 12 January 2006 (UTC)

But not with just 120kN of thrust. Face it: There's nothing special with F-22's airframe that makes it supercruise, it also does it just with large amounts of thrust, having some of the most powerfull engines ever installed in a fighter. In fact because of its fuel hungry engines its supercruise range isn't greater than a 50 year old F-104A-19's[1], and the F-104 has rather short legs. - Alureiter 02:03, 12 January 2006 (UTC)
Ohhh, so now where looking at the imfamous Col. Everest E. Riccioni "report" eh? Slander written by a lobbyist... hmmmm. Also not factually supported either. This is the same guy who said the F-15C was a step in the wrong direction and that the US should focus on building dogfighting aircraft without radars... Not the man Id want running the air force... Ricconi wants future air combat to be like WWII all over again, close in dog fights. In addition to which: do you have ANY hard evidence as to the range of the F-22A on supercruise?

"There's nothing special with F-22's airframe that makes it supercruise" - Aside from the fact its designed to carry ordinance internally and free of drag-inducing weapons stations? Skrip00 03:11, 12 January 2006 (UTC)

Some more evidence=

http://www.codeonemagazine.com/archives/2000/articles/oct_00/f-22/f22_1.html "Level acceleration in military power or less is sprightly at all altitudes but downright astounding in full afterburner. I wish I could state some acceleration times, but they remain classified. Approaching Mach in military power, the acceleration reduces slightly as drag rises, but the aircraft punches on through easily. Accelerating through Mach in military power in the Raptor feels similar to accelerating in full afterburner in an F-15. ... The best seat in the house for supercruise is from a chase F-16 or F-15. Remember, we fly both these chase jets with just a centerline fuel tank to give them a fighting chance to play with the Raptor. Still, the F-22 usually leaves these aerodynamically “slick” chase airplanes in the dust. The F100-110, -129, and -229-powered F-16s don’t fall very far behind the Raptor in the initial acceleration through Mach. But the race is really no contest at the higher Mach numbers and once on cruise conditions. Nothing can sustain supersonic conditions with the persistence of a Raptor. Load those chase F-16s and F-15s with combat-representative stores and they would not stay with the Raptor during acceleration or sustained cruise.

Invariably, our test mission runs are dictated by the fuel state of the chase aircraft. A curt “Bingo” forces us to decelerate and take the chase to the tanker for more gas. The Raptor always has lots more supercruising fuel left. I would be a pretty upset taxpayer if this next-generation fighter didn’t show clearly superior capabilities over anything flying today. While the Raptor is superior in many areas, the airplane is truly unsurpassed when supercruising."

"Nevertheless, in an article on the FB-22 in Air Force Magazine, January 2005, an image of a slide from a Lockheed FB-22 proposal indicated the F-22's combat radiuses as:

- With a supercruise of M1.5 for 100 NM: 405 NM (750 km) - With a supercruise of M1.5 for 50 NM: 455 NM (840 km) - High-subsonic speed in whole mission: 595 NM (1,100 km)

Note that this is radius, not range. Unfortunately, it does not indicate what the altitude profile is (hi-lo-hi, etc), or any other conditions such as reserve fuel, any loiter time, etc, so it is difficult to make an apples to apples comparison with anything else." http://www.afa.org/magazine/Jan2005/0105raptor.asp Skrip00 12:23, 12 January 2006 (UTC)

But this raises an interesting point; by your numbers, even the F-22 is incapable of going supersonic for more than a small portion of its mission. Heck, 100NM at M1.5 takes only about 7 minutes, and even doing that severely reduces the combat radius. This is in direct contrast to the Concorde, which spent most of its service life at supercruise (well, actually, it spent most of its life sitting in hangars, but anyway...) Another point that should be made is that the SR-71 may have run on afterburners but was actually designed to do so for long periods...
Another interesting one that might be eligible for the list; the Tu-160--Robert Merkel 05:50, 13 January 2006 (UTC)
But this raises an interesting point; by your numbers, even the F-22 is incapable of going supersonic for more than a small portion of its mission. Heck, 100NM at M1.5 takes only about 7 minutes, and even doing that severely reduces the combat radius.

Well the problem with my numbers is that there is no way to compare them to other aircraft. Im sure many aircraft can fly at M1.5 for 7 mins, but what are there combat radii? I figured for most fighter-aircraft, after that duration of afterburner, theyd need to refuel ASAP. They wouldnt have a combat radius of over 400 NM...

As for the Tu-160... im not sure it can supercruise... but like I said, without clarification of the definition itself, this list is gunna get longer and longer...


[edit] My to this dick-swinging contest

All gas turbines work most efficient at their max rev (=max power) settings, so your claim is bogus.

Standing still, yes. However, in flight, efficiency is affected by airspeed as speed correlates with the amount of air delivered. On the large scale, the optimum cruising speed ranges from piston-driven propeller<turboprop<high-bypass turbofan < low bypass turbofan < turbojet < pulsejet < scramjet.

Specifically for the question of supercruise, the bypass ratios for fighters has been declining in order to allow faster crusing speeds. I'm having trouble looking up the numbers, but it seems like the F404 was ~1.5:1 and the F119 will be 1.2:1. This probably places the point of max efficiency near or at the speed of sound.

[edit] Why is the Avro Arrow on the list?

Did it ever really supercruise in its short lifetime?

The Arrow article doesn't mention such an ability. I suspect some Canadians are convinced the thing could fly at supersonic speeds backwards underwater on one engine...--Robert Merkel 05:31, 13 January 2006 (UTC)
... and upside down. --BillCJ 19:51, 1 October 2006 (UTC)
I vote for its removal then... Skrip00 22:12, 17 January 2006 (UTC)

I removed the Arrow reference as it was not contested after nearly 10 months. --BillCJ 19:51, 1 October 2006 (UTC)

[edit] Mig 1.44 dispute...

Did this aircraft EVER supercruise? It seems to be very similar to the Avro Arrow... From what little i can find, the aircraft had 1 or 2 tesflights before being shelved.

[edit] F119 Engines

One other point to consider is that of all the fighter-class engines out there, only the F119 is designed for sustained supersonic speeds. It does this through extensive use of titanium and innovative cooling techniques.

[edit] Tu-144 detail

I was a bit baffled about the revert of my edit yesterday which added detail of the TU-144's supercruising capabilities. There was no detail anywhere about why it was reverted, so I have put it back. It was all accurate and correct, and any extra detail is clearly a good thing. If anyone wants to tell me what was wrong then please say so here. The edit was coupled with the addition of another aircraft to the list which admittedly was wrong, as i'd confused myself but the rest was good, so the good Tupolev stuff I have put back. Please do point out what is wrong with it if there is a problem. Thanks, vwozone 19:01, 23 January 2007 (UTC)

I'm a bit baffled too, since your user name has not made any edits to the article for at least the last month. If you were not signed in, it might be helpful if you told us the IP address you were on. I think I can figure it out in this case, but it might be harder in cases where there are more than one revert on a given day. - BillCJ 21:53, 23 January 2007 (UTC)

Okay, fair play - forgot I wasnt logged in at the time. Edit was made under IP: 91.109.46.60. For information, revert was made on the same day by 'Wikimachine' vwozone 20:31, 24 January 2007 (UTC)

[edit] HAL Tejas?

I wonder why the HAL Tejas is on the list. There is no claim of it being able to supercruise. The 1.4 Mach speed reached was with reheat. If it is able to supercruise, it MIGHT only be with the Kaveri engine, which is still under development, and even that is just a belief, given the Kaveri specs. Sniperz11 05:54, 2 April 2007 (UTC)

[edit] F-35 Lightning II doesn't supercruise

At least according to http://www.jsf.mil/contact/con_faqs.htm. --Edward Sandstig 09:52, 13 April 2007 (UTC)

[edit] DRDO Arjun

The DRDO Arjun doesn't supercruise either. In fact, it doesn't FLY! According to Defence Research and Development Organisation#Tank armament, it's a TANK! Looks like another case of sneaky vandalism. Sigh. - BillCJ 08:57, 21 July 2007 (UTC)