Linked Questions

51
votes
12answers
29k views

Why is the nose of the Mig-21 shaped so differently compared to other fighter aircraft?

If you look at this picture below, you will notice that the nose portion of the Mig-21 has a unique conical shape which is completely different from the nose of the F-16. (Source) (Source) So what ...
41
votes
6answers
16k views

If all fighter jets become stealthy, how will they fight each other in the future? In dogfights?

I came across this question on dogfight-capable fighter jets still being made. If all aircraft become so stealthy, how will they fight each other? Only in dogfights, I presume. Or am I wrong?
57
votes
4answers
28k views

Why can't jet engines operate with supersonic air and how do they slow it down?

Typically jets cannot operate when intake airflow is supersonic relative to the engine. Why is this so? Also, why are scramjets able to use supersonic air? To slow down the air to subsonic speeds, ...
17
votes
5answers
8k views

Why do most military aircraft use different engines than commercial aircraft?

Why do most military aircraft and helicopters use different engine technology (fighters, B52, U2, etc) than most commercial aircraft? [I removed the use of axial terminology]
16
votes
2answers
19k views

Why do military turbofan engines use a low bypass ratio?

I know that the most civilian engines use a high bypass ratio which is good for fuel economy and noise reduction. What prevents military engines from using the same technology instead of opting for ...
15
votes
3answers
5k views

What are the limiting factors for high altitude planes (e.g: U2 or SR71) preventing them from going higher?

I'm curious as to why planes like the U2 Dragon Lady and the SR71 Blackbird couldn't fly higher. What physical constraint set their operational ceiling? Pilots wore spacesuits, so that wasn't the ...
3
votes
2answers
2k views

Why are turbofan inlets circular- or oval-shaped instead of square-shaped?

Source: materialsengineeringconsultant.com and initious.blogspot.com. Most of the engines are circular except for some that are oval. The oval shape provides a better ground clearance. Why aren't ...
8
votes
1answer
5k views

How does a supersonic jet engine differ from a subsonic jet engine? [duplicate]

All jet engines have the same method of air flowing into the engine, which is compressed and ignited. What can engine designers do to make an engine design create more thrust? For example, what is ...
6
votes
2answers
2k views

What type of supersonic intake does the Dassault Rafale fighter jet have?

What type of supersonic intake does the Dassault Rafale use? Is it a Pitot Intake? It cannot be a Ramp Intake, nor can it be a Spike Intake / Cone Intake, and it does not seem as a Diverterless ...
10
votes
1answer
3k views

Is the nose cone of the MiG-21 adjustable in-flight?

In some of the photos I saw of the MiG-21, the nose cone was extended and in others it was shortened. So, is the nose cone of the MiG-21 adjustable in-flight to allow for increased/decreased air flow? ...
11
votes
2answers
1k views

What is the function of the holes in splitter plates?

Do the holes in splitter plates reduce the boundary layer, or do they serve a different function such as acoustic/vibration damping? Many splitter plates have a series of holes drilled into the ...
3
votes
4answers
1k views

What drives the shape of an engine's intake on a fighter jet?

Rectangular intakes have more corners which might increase subsonic pressure losses and would weigh larger than a pitot (Semi-circular) type intake. Are the designer drivers solely based on supersonic ...
3
votes
1answer
485 views

How does a wing mounted jet engine on a supersonic airplane prevent the interference in the flow due to Shock? [duplicate]

Wing mounted jet engines face the free stream at Mach number 1 or above, and they work perfectly for Mach numbers below 1 as well, even though the free stream characteristics change a lot after Mach 1....