Sukhoi’s Next Step Towards a Fifth-Generation Fighter

Defense Professionals ^ | 1/1/2010 | Nicolas von Kospoth

[stevie_d_64]

True...

But be careful, Russian Spec Ops personnel are monitoring this thread...;-)

[Always Independent]

Let them, its common knowledge about the SR-71 and also public knowledge about their engine designs vs US. All of this has been on TV.

[ME-262]

Why is the Osprey is a failed aircraft ?

Because it was supposed to lift off like a helicopter and then fly as fast as an airplane.(400 Knots per hour)
Now it is basically just a problematic helicopter. All the maintenance issues of a rotorcraft, flies as slow as a rotorcraft, inefficiency and poor payload of a rotorcraft. There are helicopters that can do the job just as well for less and do it more safely. Mounting the rotors on a single centrally mounted pivoting pylon would have been a simple, stable, lightweight, and efficient configuration, but wingtip mounted rotors look cool. I guess it doesn't matter that it causes a million problems.
Wingtip mounted tilt rotors:
Make the wing structure heavier.
Make the craft inherently unstable.
Make any thrust asymmetry deadly.
Limits the diameter of your rotors to small and inefficient.
Causes increased cabin noise and vibrations as the fuselage is inline with the rotor.
Fuselage area inline with rotor tips is heavier to withstand slung ice chunks.
necessitate a huge and heavy transmission system running from one wingtip to the other in case of a single engine power loss.
Does not autorotate well.
And Etc. Etc. Etc.