Forum: Technology

Just made a random search on the net and came up with this: http://en.wikipedia.org/wiki/Supercruise

Supercruise
From Wikipedia, the free encyclopedia.

A supercruising aircraft is able to cruise at supersonic speeds without the use of afterburners.

Aircraft with supercruise include:

F/A-22 Raptor
Eurofighter Typhoon
Concorde
BAC TSR-2

Although supercruise is currently fashionable, it is not new; the first aircraft to exceed Mach 1 in level flight without afterburners was the P.1 prototype of the English Electric Lightning on August 4, 1954.

In general, when aircraft without supercruise travel at supersonic speeds, they use up fuel very quickly, and must be careful not to run out. This means that if a supercruise-capable fighter is attempting to intercept a non-supercruise-capable aircraft (or vice versa), the supercruise-capable one will be at an advantage.

In practice, this is also affected by the fuel fraction, the proportion of the plane's overall mass which is devoted to fuel.

So if that's the case, why are fighters like the Viper for example not supercruise capable, if it was frist achieved with the British Electric Lightning, a 1950's fighther nonetheless!!!

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I have heard this before too...

My guess is that just because technology is researched, or even fielded, doesnt meen its yet practical. Look at WW2... We have found that Hittler had plans for a stealth bomber. At that it looked surprisingly similar to ours. (A wing shape) But one didnt become a reality for almost 50 years later...

The p.1 was apparantly a prototype. Which meens it probably didnt have to carry weapons or stores on it, or the systems of a modern fighter, making it very light....... and barely able to supercruise. When you add those neccessities on ... see my point?

Thats my best guess anyways....

-Aaron

I've supercruised the viper a couple times. The difference is that while I'm talking about Mach 1.04, the F-22 is probably M1.5 or greater.

STBYGAIN, you've supercruised a Viper? Is it rare to supercruise a viper or farely easy depending on the weather or the planes weight?

Last edited by STBYGAIN on Jul 15, 2005 - 01:29 AM; edited 1 time in total

Depends on altitude, configuration, and motor. I was in a Block-52, not much else hanging on the jet, and about 42,000'. I needed AB to get above the mach, but I was able to sustain supersonic speeds without any AB. It's not something you'd see or do very often, especially in a combat configuration.

Also keep in mind that the Viper has a fixed inlet (not optimized)...means conditions have to be perfect.

On a different note, when the YF-22 and -23 were in the dem-val, the word around was that the Eagles used as chase were in blower trying to keep up, yet the fuel flows of the ATF variants were similar to that of the Eagle.

Makes sense: it takes "X" amount of energy to move a mass through a viscous fluid, and energy = fuel. Given the size of the -22 and -23 compared to the Eagle, one has to assume that their respective drag levels are similar, and thrust equals drag in non-accelerating, level flight. Yes, burners are less efficient than the turbofan primary core, but even so the overall fuel flow had to be close. What that means in my mind is that fuel flow may be improved, but it ain't a panacea. Flying without blower also means no burner plume and therefore (1) harder to see and (2) less susceptable to IR missiles.

I think the Grumman F-11 Tiger supercruised once or twice as well.

From various sources, not only the EF, F 16 blk. 50/52, but even the draggy F 18 C with the new engines (F404-GE-402) could supercruise at ~1.2M. However, this capability is more theoretical because is achieved only in clean configuration, while the Raptor can do 1.6 M with 8 missiles. Hang something on the other planes and you'll need AB to go supersonic.

Last edited by crazyal611 on Jul 15, 2005 - 07:30 AM; edited 1 time in total

The Super Tiger prototype of the F-11 didn't supercruise, but after firing the gun and going into a shallow AB dive, it ran into the shells it had just previously fired. The YF-17 shocked everyone in 1973 by breaking the sound barrier in level flight without the use of afterburners during the LWF compitition at Edwards AFB. That was one of the few strong points that it had over the YF-16.

Last edited by Pat1 on Jul 19, 2005 - 05:29 AM; edited 1 time in total

Quote:

On a different note, when the YF-22 and -23 were in the dem-val, the word around was that the Eagles used as chase were in blower trying to keep up, yet the fuel flows of the ATF variants were similar to that of the Eagle.

Makes sense: it takes "X" amount of energy to move a mass through a viscous fluid, and energy = fuel. Given the size of the -22 and -23 compared to the Eagle, one has to assume that their respective drag levels are similar, and thrust equals drag in non-accelerating, level flight. Yes, burners are less efficient than the turbofan primary core, but even so the overall fuel flow had to be close. What that means in my mind is that fuel flow may be improved, but it ain't a panacea. Flying without blower also means no burner plume and therefore (1) harder to see and (2) less susceptable to IR missiles.

Interesting. I would have thought for equal fuel flow and no burner it would produce more thrust. After all, less energy is converted into heat without afterburner (more efficient) Confused

EDIT: at same speeds...

You guys will laugh, but guess what the fastest TACAIR platform in the US inventory is at military power.... not the Eagle..... not the Hornet, nope its the EA-6B Prowler. Hard to believe, but yeah it will go faster and farther then anything else on military power alone.

Lawman is right. Interesting too, the EA-6B is the only major warplane in the US inventory that still has turbojet engines.

Elite 1K Joined: May 26, 2005 - 08:39 PM Posts: 1496

crazyal611 wrote:

the EA-6B is the only major warplane in the US inventory that still has turbojet engines.

Putting on my pedantic hat: What about the B-52? Very Happy

Sorry, but those now have turbofans Wink

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Elite 1K Joined: May 26, 2005 - 08:39 PM Posts: 1496

I'll be darned, and here I always thought the -52s that fly over from Minot had J-57s in them. Good god the turbojet models must have been loud. Shocked

Forum: Technology

Supercuise ain't new. WTF?