The F-22

I don't believe this is the case. Supercruise and supersonic flight are two very different things. While many planes of the last two gnerations arecapable of supersonic flight, it was always at the cost of enormous fuel burn (with or without after-burners) and could only be sustained for a relatively short period of time. Supercruise aircraft are actually capable capabel of operating for extended periods at supersonic speeds. The F-22 (and Typhoon, though apparently to a lesser extent) engine technology greatly imoprve and extend the amount of time the aircraft can operate at supersonic speeds compared to earlier super-cruise aircarft.

 

Raptor has about the same supersonic range than what a 1960 f-106 Delta Dart had. The energy required the plane to stay in supersonic speeds doesn't change with the engine running in non-AB or in AB mode, thus fuel flow is about the same with a chase plane running supersonic in AB next to a Raptor that runs supersonically in dry thrust. This is an old pic I found about Raptor ranges in Airforce Academy article: http://www.afa.org/magazine/jan2005/0105raptor3.jpg

The advantages for supercruise comes from the fact that Raptor is able to extend the range that Raptor weapons have (Oli is right with his pole thingies). Currently it's not tactically feasible for a fighter to use AB to get in high supersonic speeds because afterburner acts as a huge "HEY, LOOK AT ME!" sign. Modern battlefield is crowded with all kind of IR sensors and decreasing IR signatures are sougth after (just look at the IR devices that the Russian planes have). Afterburner also increases radar signatures drastically (the plume acts as a radar deflector) With supercruise, you deny sensor advantages off from the enemy at the same time when you can safely increase the effective range of your own weapons.

 

what do you think of the contention that the F-22 isn't a necessary addition to the USAF? Many seem to think that the F-22 is too ridiculously overpriced, and it is not necessary because air superiority already belongs to the comparitively cheaper F-15 Eagle. Although this may be true, i dont think it is ever a good idea to waive a technological military superiority, the USAF should not 'wait' until the F-15 becomes obsolete before replacing it or they will leave themselves vulnerable. They should adopt the F-22 now. That said, it seems to me that the F-15 is already obsolete. As demonstrated in the IAF test, every time the F-15 has been combat tested against the Su-27 Flanker it has lost by an embarassing margin, (another example: http://mysite.wanadoo-members.co.uk/fla ... ombat.html); another reason why the F-22 MUST replace the F-15.

 

Regardless of whether the Su-27 is better than the F-15 or not, the unescapable fact is that the Su-27 is at least good enough to give the F-15 a very hard time. For that reason alone, the USAF needs the F-22.

Besides, how does the F-15 perform compared to the latest crop of European fighters (Rafale, Eurofighter, Gripen, etc)?


Bottom line - Why maintain parity when you can have superiority?

 

Don't quite understand this. It's is a fact that lighting afterburner increases the fuel burnt by a very large amount, since raw fuel is injected straight into the exhaust in addition to the normal amount used inside the engine itself. F-22's engine is optimised for a high dry thrust and low sfc (specific fuel comsumption - measured in lbs of thrust per lb of fuel burnt per hour, or kg/kg/hr) and to have one of, if not THE, highest, dry thrusts available in a military aircraft today. Most current aircraft engines are not so optimised, and thus require considerably more fuel to run in afterburner to get supersonic speeds.
The F-119 engine on Raptor has sfc's of about 0.82 in dry thrust and 1.7 in afterburner, and the F-100 on an Eagle is about 0.7 and 2.5 respectively. So the the F-22 uses about twice as much fuel when it needs afterburner, whereas the F-15 uses three and half times as much.

 

And the SR-71 does Mach 3 without after-burners. What does that tell you!

 

That somebody has been feeding you a line.
I'd like a source for that. You might like to know that the engine itself on SR-71 provides only 17% of total thrust when running at full speed, the rest is from extremely clever inlet and outlet confgurations that turn the entire powerplant (including nacelles) into turbo-ramjets - and a ram jet by defintion is nothing BUT afterburner. All of the fuel (on a ramjet) is burnt in the exhaust.
If it does Mach 3 without afterburners why are they fitted?
http://www.wvi.com/~sr71webmaster/j-58~1.htm
http://www.sr-71.org/blackbird/j-58/
etc. etc.
Try

My italics. From http://en.wikipedia.org/wiki/SR-71_Blackbird

 

....wow, I've been told. Sorry about that, I was arguing with a guy over whether the JSF is VTOL or not and i must have gotten confused about something (I lost the argument...lol). I dunno, I never really clasified a ramjet as an afterburner although on second though...yeah,ok I see now.