SU-27 Vs Grass

The cobra maneuver always leaves my jaw hanging....it really defies gravity.

There is a cool video I'll have to find on Youtube where an American pilot is saying that the Russians have always built their plans with superior dogfighting ability, and the US has focused more on missiles and electronics.

jet engines really don't overheat, think of it as a propane torch.

the temperature is greater at the tip of the flame, ie; the tip of the Afterburner

the actual Torch tip is cool, or warm to the touch.  < the copper pipe your heating turns red, but why isn't the torch tip?>

Cold air...engines generate more Thrust, HP, whatever.

cold air is denser, meaning more of it can get in the same space. think cold air filters, or intercoolers for turbochargers <little turbines>

BTW Relm is the physics guy..ask him about thermodynamics

But not really in the way you are thinking.

And it all depends on the particular engine and how it is designed. When a jet turbine overheats the turbine blades get hot and brittle. They also have torque stresses on them and if you try and throttle up after they have overheated they can shatter (sortof).

An idling engine, or at low throttle (such as taxiing) the engine doesn't generate that much heat. But at higher throttle loads over a longer duration the heat buildup can lead to engine failure. I haven't actualy watched the video above (no YouTube at work) so I am not sure what is happening there. But short duration at full throttle/afterburner would most likely not be enough to cause a failure.

A good example of controlling engine temperature is the harrier 'jump-jet'. The harrier carries a small water tank on board. When the aircraft transitions to STO (short take off) or VTOL (verticle take off / landing) mode the water get sprayed into the compressor blades to lower the engine temperatures. The airplane only carries enough water for about 90 seconds of hovering.

This is not the same sort of water-injection system used on other aircraft. Some aircraft, particularly aircraft that may have to take-off with very heavy loads (the B-52 has this system) have water tanks with injectors in the compressor-section of the engine (just before the combustion chamber). The water hits the hot exhaust gasses and vaporizes increasing the air-pressure across the turbine blades and increasing thrust, similar to after-burners but without raising exhaust gass temperatures (actualy, it lowers them). If you ever see a heavily laden B-52 take off and the engines are spewing black smoke it is because they are running the water injection. http://en.wikipedia.org/wiki/Water_injection_%28engines%29

Cooling a turbine and the heat stresses it can take all depends on how it was designed. There have been several cars and motorcycles designed around turbine engines. They can take full-throttle loads and heat at speeds far less than what an aircraft reaches. Speed=cooling

http://www.marineturbine.com/motorcycles.asp <-- Jay Leno's turbine bike

http://en.wikipedia.org/wiki/Chrysler_Turbine_Car <-- 1960's chrysler experimental car, several were give to customers on a trial basis

Even tanks get in on the turbine action:

http://en.wikipedia.org/wiki/Abrams_tank

The big problem with turbine ground vehicles is that throttle response is much, much slower than piston engines. A turbine can produce a lot of horsepower, but they don't actualy produce much torque. So they have to spin up to incredible speeds (most don't hit their stride untill over 15,000 rpm). And throttling up and down they take a while to respond. Straight line speed can be incredible, or in aplications where constant throttle is all you need they are great (those hydro-foil racing boats all use turbines now).