Ski jumps - why do they work?

[Cron]

I'm sure it's obvious, but I can't see it. Why does a ski jump offer an advantage to Harrier performance? Thanks in advance for information.

[Mark 1]

I had wondered this too, and in the absence of any more informed answer, this is what I think.

At the speed attained at the end of the runway there is insufficient elevator/pitch authority to raise the nose and use wing lift to augment the vectored lift-thrust.

The ski jump allows you to become airborne at a higher angle of attack than would otherwise be possible, and once the weight is off the wheels full elevator control is available.

There is also the advantage that an intermediate nozzle angle can be selected as the pitch-up provides additional lift component.

I stand to be corrected of course.........

[Cron]

Thanks M, I'll try a poat on Rotorheads

[chiglet]

If you think about the question "Logically" and just who does?
It "seems" to be a "Self Powered Catapult" especially with the Harrier.
Accelerate [with a bit of "down thrust"] then thrown into the air, and "voila" [or is it viola?] Thrust and Lift overcome Weight and Drag :ok: Hope this helps
watpiktch

[Yarpy]

Perhaps you could post this question on the Flight Testing forum.

John Farley might pick it up and give you the definitive answer.

[Heliport]

John Farley has given the definitive answer in the Rotorheads Forum.


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