Techie question

[Farrell]

Received the following by email.

I am not a rotary wing nut so I decided to ask it here. Don't shoot the messenger:

"A quick (Or long) question for you! When was ability to diconect the drive and allow autogyration first implimented into helicopter design?"

Thanks chaps and chapesses

Farrell

[Farrell]

Come ON!!!!!

[forget]

In 1939, Flettner's Fl-265 synchropter flew successfully and was the first helicopter to demonstrate transition into autorotation and then back again into powered flight.

A History of Helicopter Flight

Now get back to work.

[Farrell]

Thanks mate

[HELOFAN]

Juan De La Cierva designs

Actually, if you look in to Autogyros, gyrocopters...whatever you want to call them & look at Juan De La Cierva as he had designed the first Autogyro. He had designed the flapping hinge and after it was first built it also suffered an engine failure and Auto'ed to the ground safely.

I would expect his designs were the first to allow a disengaging drive system from the pre rotative drive systems.

From there the helicopter the helicopter took off and most certainly had a clutch system incorporated along with the flapping hinge ..etc etc.


It was pre 1939 for sure though designs were always being copied and borrowed & improved.

I would look at the C30A (built in 1934 & designed earlier) closely for designs in the drive system as the rotor system was driven by aux drive from the engine.

From there you could look at Pitcairn (built under license from Cierva).

Prior to that (Cierva)...not sure, no one else was succesful in getting them to fly though maybe someone did think of the clutch drive .....but I would be surprised.

Now if you want to get anal you could think of Sikorsky as him having the first sucsessful helicopter design SV-300 in 1938-39.

Prior to him I would look at Frenchman Louis Bréguet and German Heinrich Focke as they had both heavilly contributed in the early 1930's to helicopter design.

You may get caught out when you read something that states somebody built something. Yes they may have built it but that doesnt mean they designed it.



HF

[Farrell]

HELOFAN!

Awesome! - will pass it on to the guy.

Farrell

[topendtorque]

I doubt that any serious rotary designer would have ignored it, after all they had plenty of examples around.

Such as all of the threshing machines or harvesters, which have been around since the steel age, all of which incorporated high inertia rotating components, (to thresh the grain out of the head) with a free wheel device to stop catastrophic failures from back loads, should there be a sudden cessation within the drive system.

The Sunshine series of harvesters sprag clutch was almost identical to the R22, albeit a much heavier device.

I should have added, many of which were horse drawn. horses stopped, everything out the back happy!!

[RVDT]

And most work like this Free-Wheel Clutches - Sprag Clutch Technology - GMN Bearings

[Dave_Jackson]

In this web page Focke-Wulf Fw 61 ~ 1936 it says;

"the Fa 61 made its first flight, of 28 seconds, on 26 June, 1936, and made its first autorotative landing in May the following year."