Gravityisnotmyfriend

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I had a Kombat Kopter a couple of years ago and managed to fly it with varying degrees of success. It had some issues that caused me to eventually dismantle it and give up on gyros for the time. It was a single rotor and had the issue of asymmetrical lift at low rotor speeds - which made ROG takeoff nearly impossible. It also did not have fore/aft tilt on the rotor which would have helped get the rotor up to speed quicker. This also caused the craft to pitch up - nearly uncontrollably when turning from downwind to upwind.

A DC head would take care of the pitching issue and would probably help ROG abilities, but I'd still have the asymmetrical lift issue. So, I was think of going with a twin rotor setup - but I still wanted DC heads on both. Then it dawned on me that I may be able to build this craft without side/side control on the rotors.

Instead, I'll have fore/aft control on both rotors - each controlled by their own servo. Then, I would mix them like elevons. Pulling back would tilt both rotors back. Right stick would tilt the right rotor back and the left rotor forward. Left stick would be the opposite.

Any reason why this wouldn't work? AFAIK, this hasn't been tried before. I've done some searching, but came up with nothing.

ottogiro58

Hello, I believe something similar to this arrangement has been tried by billf (Dr. Bill Friedlander) and can be seen on a video posted on this forum (and You Tube) previously. I think it was You Tube-Spring Hill 2007 Part 4. It did fly, but I am not sure if any further development was accomplished. Might be a heavy servo load to deal with, unless a type of offset gimbal mount is used. Charlie A.

Gravityisnotmyfriend

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Why the heavy servo load? Or rather, why would the servo load be any heavier than with a single rotor DC head?

I can't access Youtube at work, but I'll have to check that out when I get home. Thanks for the tip!

billf

Hello "Gravity..."
Charlie is correct. I did fly (briefly) a twin rotor gyro with articulated rotors on either side at the Spring Hill fly-in a couple of springs ago.
I am planning to be at the Morris, Il get together in Sept and will have it along. Thanks to Phil Ploof's suggestion of using a FMA Co-Pilot,I am hoping it will be a bit better behaved. I used a PT profile kit as the basis for the aircraft. Getting the location of the outrigger tubes in relation to the CG was a bit of a challenge since there is no pylon...the tubes emerge right out of the fuselage.

This design was inspired by Ralph Kalf an engineer from Milwaukee who visited with us in the early days of trying to get autogyros off the ground.

By the way at one of the early fly-ins in Hudson, WI, a couple of fellows from Worthington MN showed up with a gyro with articulated
booms that were mounted atop a conventional trainer-type fuselage. As I recall the plane flew well and did roll very well.

Hope you will join the fly-in at Morris on Sept 5,

Regards,
BillF

Gravityisnotmyfriend

My Feedback: (2)

Good to hear that the twin articulated head design works. After doing a bit more research, I've decided to start a bit simpler. I'm going with a 3 bladed DC head design on a tractor fuselage. I'll see if that takes care of the stability issues I had with the Kombat Kopter.

I've finished the rotors and head. I've go alot of projects around the house, so progress is slow.

Thanks for the invite to Morris. If I've got a flying Gyro in Sept, I'll have to make the trip.