Autogyro idea

[Barron 64]

Hello,


I am curious about using an Open Ez ( Long Ez ) fuselage, gear, canopy, controls, ( but no wing strakes, have to come up with fuel tank"s" somewhere ) and using this for the "starting point" of an autogyro idea I have. This will not be an ultralight. What are your thoughts on the matter.



Thanks

Barron

[WHY]

Well Barron

You have got an idea there, I think it would have to be built something like a Twinstarr, obviously would have to be a pusher, also have a pylon for the rotor and there would be no problem with gas tanks because you are going to need some sort of short wing structure at the rear for LARGE TWIN rudders so put the fuel in the stub wings. My only concern as it sets would be the GROUND balance on the landing gear. Balance in the air would be achieved with the proper location of the pylon.

Tony

I think it's do able

[Barron 64]

Tony,

I think it is do able also. I have seen a couple of Twinstarr's before and thought that type of configuration would be the way to go. I need to find some build information or construction plans on that type of pylon build. I was thinking about the ground balance as well. Perhaps an engine mount that hangs the motor a bit further aft ??

Thanks

[WHY]

I think you will want larger wheels on the main gear and may have to re-work them for a wider spacing. Have always been a little wary of the nose gear for strength.

What engine do you have in mind, aircraft (O-360 ) or automobile converted ??

Not great deal on the pylon, 4 post braced, but this will for sure require a "slider head " for the rotor reasonance or you will start cracking the pylon at the weld joints.

Tony

[Barron 64]

Larger wheels for sure. I have lots of ideas but not sure just yet, but I am thinking a converted auto engine, maybe 150 - 180 hp ? But how much HP is too much in an autogyro ?

Barron

[Vance]

Hello Barron,

I feel you have a fine start for a two place tandem gyroplane there.

I recently looked at just that idea and rolled the two place tandem gyroplane I am flying up next to it.

Things seemed to be in very similar positions.

I like the main gear a lot.

The wheels, tires and brakes were the same size as mine.

I feelk the nose gear is fine.

The rotor mast has a lovely strong place to attach.

The keel and empennage would take some thinking.

The one I looked at was set up for a small Continental.

It had a very nice cowl over the engine and the cooling looked well done.

I suspect I could have bought it for less than $500, perhaps much less.

It is still a very large project.

My gyroplane has a Lycoming IO-320 with 160 horsepower, more would be nice.

Good luck, Vance

[Barron 64]

Thanks Vance, I think it is a decent place to start. In the back of my mind I have this thought "as much HP as possible". I certainly don't want to over power it but I do want to have more than enough.



Barron

[WHY]

Barron, over in the "fixed wing world" there have been some nice V-6 conversion with 200 + hp, of course they all run re-drives on the prop.

Tony

PS you could start something big !!!

[Barron 64]

Yeah I have seen a few of those when I was back home late last year. With 200 + hp I think it would move pretty well, but my immediate concern is pushing it through the air with all that power and stalling rotors. Not to mention the weight of the engine and the PSRU.

[WHY]

Barron

While this set up would be VERY streamlined and aerodynamic, the top speed is going to be somewhere in the vicinity of 100 mph, unless you want to try to get into some of the more exotic set ups like Cartercopter,. Yes, it is going to be a heavy machine, so a heavy engine will actually be a good point toward balance, and all that hp does not have to be used all the time, just cut back and cruise with great economy and if you need to CLIMB, you got it. One point I would recommend, and that is when you make the tower/pylon and produce the re-inforced attachment points for it, shock mount all 4 points at the base where it attaches and then make a floating fairing for the whole tower. But if you are going to use a "teeter" rotor system a 100 mph is going to be about it for safety.

Tony

Tony

[Barron 64]

Limited to 100 due to weight and drag ? As the fuselage sits it is about 150 pounds. I would certainly put a fairing on the rotor system and in the rear. Good point shock mounting the rotor system. I am interested in doing a little better than 100 honestly.

Barron

[Vance]

Hello Tony,

What do you feel would limit the top speed to 100 miles per hour?

The gyroplane I am flying now seems to fly at 95 kts, 109 miles per hour, straight and level solo with a 160 horsepower Lycoming and very little effort to streamline anything.

At close to 1,400 pounds with full fuel and a passenger she still flies at 90kts, 103 miles per hour.

In a slight descent she will see 110 kts, 126 miles per hour.

It seems to me that a nicely done enclosed gyroplane with a cowl would see a reduction in drag from the body and landing gear of 50% making a 90kt cruise at 75%,120 horsepower a reasonable goal.

A 180 parallel valve Lycoming weighs the same as my 160 horsepower engine.

What am I missing?

Thank you, Vance

[Arnie Madsen]

Barron 64

On one napkin make a drawing of the mechanical components like the mast and engine placement and seating arrangement and tail surface you feel might fly the way you desire.

Superimpose the second napkin of your Long Ez fuselage over top of the mechanical drawing and try to marry the two.

I am not qualified to give you any advice, but I like your ideas. Thanks. The best ideas start on a restaurant napkin, the ones that work use two napkins.

I am enjoying this thread and your ideas.

Arnie

[WHY]

Hi Vance

I was basing this on some comments made on the subject a few years back when the subject of rotor incidence was discussed and that was the speed that seemed to come up, stating that around 100 mph the incidence was gettin so near flat that a possible "rotor tuck" was getting close, however I would concurr to your experience with the Predator as it would be somewhat close to his general configuration except for the twin tails. It has been long enough that I do not recall if the 100 mph was for a specific model or not,so I may be quite wrong here, thanks for the actual hands on experience reply.

Tony

[Earthboundmisft]

My opinion; sell it, take the money and go buy some 2x2 aluminum tubing, and start building. An aircraft, more so than any motorized vehicle, needs to be as light as possible. Why build a tank? Why the desire to be all closed in? Thats what fix wings are for. The Dominator 2 place frame is the lightest, if you want a 2 place. "thats all I got ta say bout dat".