The catch 22 of autorotation on gyroplanes

Resasi

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Bit of a hot dogger then Mr Beaty.:)

I’m hoping most doesn’t include Denis, and your calculations for DW’s will be close for his Razor Blades.

Remember seeing that machine flying at Bensen Days, though not with you at the controls.
 

C. Beaty

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Bit of a hot dogger then Mr Beaty.:)

I’m hoping most doesn’t include Denis, and your calculations for DW’s will be close for his Razor Blades.

Remember seeing that machine flying at Bensen Days, though not with you at the controls.
That was Pier Luigi D'Armi, an Italian visitor to Bensen Days taking his first flight in my gyro.

In fact, I let anyone who wanted to fly my gyro. We used to have a large Japanese contingent to Bensen days and nearly all of them flew my gyro.

Once, I noticed a fellow with several cameras slung around his neck eyeing my gyro so I asked him if he wanted to fly it. Shocked, he said sure. As it turned out he was the editor of the French ultralite magazine, Vol Moteur and he did a nice writeup with that gyro on the front cover. Unfortunately, my place was flooded and my only copy of that magazine was ruined.

It only proves that free castering nosewheel with steering via mainwheel brakes is pretty much foolproof if the suspension geometry doesn’t introduce a lot of tire scrub and pole vault everything sideways. The main wheel track is a bit less than 4 feet so that a trailer could be built using a single sheet of plywood.

The footpegs were designed for heel steering but most people dropped their feet down and used my heel pegs as toe pegs.
 

Resasi

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That was Pier Luigi D'Armi, an Italian visitor to Bensen Days taking his first flight in my gyro.

In fact, I let anyone who wanted to fly my gyro. We used to have a large Japanese contingent to Bensen days and nearly all of them flew my gyro.
It certainly seemed to perform well, and how refreshingly trusting of you.
 

C. Beaty

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It certainly seemed to perform well, and how refreshingly trusting of you.
With a 503 Rotax, my gyro was almost overpowered with Pier Luigi; ~130 lbs and for most Japanese pilots.

I was never concerned about the loss of the gyro; everything except rotor and engine was homemade and didn’t represent much of an outlay.

The biggest concern was liability in the event someone was injured or worse.
 

Inquiring Mind

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If you know the rotor diameter, tip speed tells you how many rpm the rotor must run at.
I see now. Thank you, Chuck.

So, for 28' x 8" rotor over 1320 lb of gyro weight, blade loading is ~71 lb/sq.ft and tip speed is ~555 ft/sec, which equates to ~379 Rotor RPM. It is about what I see in flight on M-24 - anywhere from 360 to 420.
Life is good! :)

Thank you, Chuck!
 
Last edited:

MilesW

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Sportcopter M912
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In my opinion a round tube has more drag than a square tube of the same diameter.
Everyone is entitled to their opinion, but the facts are -
A round tube has a Cd of 1.2
A square tube has a Cd of 2.2
A square tube with rounded corners has a Cd of 1.2

Miles
 

ferranrosello

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Chuck, thank you for your explanation.
Certainly 1950's Spain was very different. And the travel tour are talking about would be very close to an adventure (Spanish roads were very bad in the fifties). I hope it was a nice trip.

Ferràn
 

Jean Claude

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I piloted gliders C800, Bijave, C 310, airplanes Piper J3 , PA 28, Jodel D117, DR 220, Cessna 150, C
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JC, I wish we had made accurate measurements. With flapping limiting top speed, my guess is that mu would have been considerably higher than 0.5.
Thanks Chuck. But I would like to know mu found in your measurement at 20 mph, stick on the forward stop.
 
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