Why the Black Hawk has a T/R on the RHS
Hi,
About the Black Hawk. One of the design concepts of the BH was that it had a fully flying horizonatal stabilator, ie it is horizontal when in flight and as IAS decreases, it begins to droop down. Why? Well it increases the lift on the tail at low speeds.
But also for the following reason.
The Tail Rotor on the Black Hawk is huge and provides a lot of thrust. It is also canted so that it is not rotating in a vertical plane. It is actually tilted about 20 degrees from the vertical. (I think it's 20 deg. Can't remember).
What's more, it is designed to 'pull' the tail to the right unlike other rotorcraft where the tail rotor is designed to push the tail to the right. (That's why it's on the right and not the left of the vertical stabilizer).
Because of that, the T/R's significant rotor wash can also be used. Because it is forced to the left AND DOWN, the downwards vector provides about 400 lbs of lift to the tail... and because the horizontal stabilator is now 'drooping' down, there is no obstruction to this downwards force.
So there you have it. The Black Hawk's tail rotor pulls the tail to the right and the downwards component of the tail rotor rotorwash pushes the tail up. More efficient use of tail rotor aerodynamics.
I hope that makes sense.
Cheers
Conway
About the Black Hawk...
Sorry, forgot to add.
It\'s a UH-60 Black Hawk... but the civilian version, which Australia bought as a militarized model, is the S-70. UH-60 is military designation, S-70 is Sikorsky model number. S-70A-9 is the Australian version of the Black Hawk.
Sorry to be a pedant.
Conway