Could I steer this thread towards the same concept, only in a

coaxial

helicopter? :)

My (shade tree mechanics degree) says two engines in a coaxial
configuration could be interesting. :) If one engine *could*

provide

enough power to maintain altitude, couldn't you toss the need

for

autorotation? I'm ASSUMING the reliability of the rotary built

for

proper aircraft use.

I know something along this line has been tried by the Nolan

brothers

(two small two strokes)...I have a different twist in my head.

I need

massive help!

Thanks guys
Phil

The problem with seperate engines on a coaxial helicopter is that

the torque

differential would show up on the tail (rotor etc), and a single

engine

failure
would spin you like a top.  A more direct coupling would be in

order

for that application, and I do not know if you could sustain on

half

power.  maybe crash more softly? Vance

If two engines drive the same input shaft to the transmission, and are

coupled through a

mechanical diode, or sprag/overunning clutch, the loss of one engine

will just reduce the power,

but not have an effect on the fuselage since the torque is being

counteracted by the two rotors

running in opposite directions.
One rotor inputs counter clockwise torque to the fuselage, and the

other inputs clockwise torque,

thereby cancelling out the torque.
The same as a tandem rotor.
Here is a link to a page that gives some details on a good coaxial.

Gyrodyne

Royce

Thanks for the Gyrodyne link Royce. I'd been reading through some of
their files for about 9 months now.

The thinking behind this madness is to *attempt* to eliminate the extra
linkage/hardware to the top rotor...KISS. This would toss autorotation
out the window, but it does bring in the extra hardware to utilize two
engines. Also, from what I've read, coaxial isn't as "auto-rotation
friendly" as the standard one rotor/tail rotor set-up.

Take a McCulloch J2 gyro, toss powered coaxial rotors on it, and that's
(mostly) what I'd be looking for. :)

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