My gyro project.
 

When I mentioned to my flying buddy that I was going to build a gyro, he said I've got plans for one! Wow, I'd never heard him say anything about a gyro before, so I went over to his house and had a look. He had plans and the magazine article for a Focke-Achgelis 61, by Model Builder, post marked 1975.

http://www.autogyro.com/models/la~fa61.htm

It looked pretty cool, but I wanted something a little bigger having just built a Ryobi powered plane:

http://www.netlabs.net/hp/soarrich/G-BRIT.html

I weighed just the body of my G-BRIT and it weighs 9 1/2 pounds, so I think a similar sized gyro should come in at around 11 to 12 pounds, well with in the Ryobi's abilities, the G-BRIT is 16 pounds and is nicely powered.

While I was in Florida I spoke with Les Garber, he said the FA-61 was a nice flier, but suggested that I make it a tail dragger.

http://www.netlabs.net/hp/soarrich/fw-61.jpeg

I may make that one, but I like the looks of this one better.

http://www.netlabs.net/hp/soarrich/fw-61-s.gif

I'm thinking if I put the engine at 0*, the rotors at +15*, and the stab at -5*. I would have basically the same aerodynamically as a tail dragger on the ground, with the added benefit of the fuselage would fly level or slightly nose down, this wasn't a autogyro, in really life the FA-61 was a helicopter.

I'm going to be using delta hubs, held out about 39" from the center line on carbon fiber shafts. My 2 rotors are each going to be using 3 36" blades, making disks of about 74-75" diameter. I'm going to put one servo in each rotor to adjust the rotors in the pitch axis, using mixing in my radio set for elveron control, so this will be a DC gyro with rudder.

I'd like comment on:
1 Is my 0,15,-5 workable?
2 Is the elveron idea workable?
3 What size servos in the rotors? I'm thinking 131ozMG from HiTec.
4 This is for you engineer types. I'm thinking the rotors are going to point load the carbon fiber shafts at the end, not span load it like a wing, so do I strengthen the shafts in the center of the span like a bridge, or taper it out to the rotors? I think I should strengthen it in the middle.

Dual Rotor Autogyro
 

Hi Rich,
This sounds like this autogyro may be your first. I have built several dual rotors with servos to control the incidence of the rotor heads. I did use the 132 oz servos that you mentioned and using mixing in the radio was able to change the incidence in the rotors with one increase and the other decrease. With the helicopter radio I could also adjust the overall incidence of both rotors while flying. I tried mounting the servos under each rotor head and also mounted on the fuselage and rotate the shaft to the rotor heads. The only thing that I was able to accomplish that I couldn't do with just rudder was a beautiful flat spin that I couldn't always recover. Also, with throttle back on the engine and putting a lot of incidence in both rotors prove kind of interesting. Nice air brake. I also built a dual rotor that the booms holding the rotors were hinged on the fuselage and I could rock the rotors up and down. Again, same results as using rudder. I would start with a long fuselage, 4 degree engine down thrust and 6 to 8 degrees rotor head incidence. (relative to center line thrust) Hang angle -10 to -15 degrees. Set the booms hold ing the rotor heads at about +15 degrees and tilt the rotor head pins (shafts) out about 4 degrees. This will help the rotor blades clear the booms. However, I am very interested if you build it with the servos on the rotor heads. Maybe you will find out something different.
Good Luck Phil

My gyro project.
 

Phil
Good point, I had not thought about tilting the head pins outward to clear the booms. Thanks.

Your Project
 

Mr. Soarrich....??????
You mentioned in your post that a Mr. Garber suggested to you that perhaps you should try to build your twin rotor gyro model as a tail dragger.........

You responded with the notion of designing your model with the appearance of a tail dragger while on the grouind......

I trust that Mr Garber was in fact suggesting that you build your model as tail dragger as in, have a tail wheel rather than drag its tail while in flight........

With all due respect might I suggest electric trains of perhaps boats might be you cup of tea......

My gyro project.
 

No, I wrote:You may not understand the logic of the settings, if you minus 5* from all those listed you come up with the classic -5* down thrust, rotors at +10*, and stab at 0*. It's the relationship to one another that matters to the air. By picking the settings that I did the rotors will "see" the air as if it was a tail dragger. but still retain the nose wheel like that of the full scale.

I'm sure he was suggesting that I build it as a tail dragger, he didn't DEMAND it though. I assumed he suggested building it as a tail dragger to get the extra angle of attack, ( about 5*), that a tail dragger gives you. The settings I am going to try will give me that extra +5 degrees. -5* nose down from the way gyros normally fly, which from what I've seen tends to be nose high would help to level the body in flight, though I would like to see it fly slightly nose down like a helicopter, which it really was.



I don't know you, English may be a second language to you, or you may just be having a bad day, or too just many beers, but try rereading, and understanding what I wrote before suggesting life style changes for others.

My gyro project.
 

Hi Rich,

Just to comment on your 0, 15, -5 idea. If you build it with those parameters, when your blades reach autorotation and you throttle up it would probably roll over on it's back. I would like to see the results if you did build it like this, but not at the expense of having you rebuild it. I know what it feels like. Many pilots have tried autogyros to only get discouraged and give up after destroying several gyros and never experienced the joy of a good flight. I thought I could fly anything, including helicopters but totally destroyed at least thee gyros before achieving a good flight. I now just buy a fuselage at a swap meet for $5.00, stick a rotor on and go fly.

I think we are talking dual rotors. Set the engine down thrust at minus 5 degrees, rotor incidence at 6 degrees and hang angle at minus 20 degrees. Unless you hand launch, a tail dragger is a must. You must have a real tall landing grear that reaches out in from with the engine and spread real wide. Otherwise, it will just ground loop before the rotors reach autorotation. If you want to try a real stunt, create a spool on the underside of the rotor hubs and wind about 50 feet of light nylon line and stake them to the ground. Go full throttle and you're guaranteed a launch. It's a great demo.

This is just my opinion.

Good luck, we need more autogyro pilots!!

Phil

My gyro project.
 

Hi Phil

This is a dual rotor.

I'm not being argumentative, just picking your brains. :)

You say:

Will it roll over, or loop over?

WOW, that sounds like it would really be cool. I think I save that for maybe the second flight! :)

I was hoping that the trike gear would prevent ground looping. One good thing about the FA-61 is even though it had a nose wheel, it also had a tail wheel. I'll build it so all I have to do is turn the mains around to make it a tail dragger, the rotors are already be adjustable.

My gyro project.
 

Hi Rich,

The most difficult part of flying autogyros is getting them off the ground and high enough to recover until you can get use to how they handle. I have seen experience gyro pilots make 3 or 4 attemps to get the gyro flying and either ground loop or abort the take-off. If you're fortunate enough to have a perfect light steady wind, take-off is easy. However, that seldom happens so you have to learn to compensate. With a single rotor you need to hold a lot of up elevator when you first start your roll-out or the tail will come the ground and it will cart-wheel before you even get started. When the rotor is about ready for auto-rotate you ease off the elevator and let the tail lift. If the timing is off, either too soon or too late, it will roll over. Practice is the only cure. With dual rotors, one rotor will always speed up faster and it will either roll over on the ground or as soon as it lifts off. Stand straight behind and watch the rotors and use up elevator and rudder to get the slow moving rotor more into the wind. I have two other very experienced pilots at our club and I have tried to help them to fly dual rotors but they both gave up and went back to single rotors. Dual rotor gyros like to have a long fuselage and a larger than normal rudder. I converted a Dazzler to an autogyro and I can roll, spin, and loop and it does these things well because of the short fuselage. However, it would not be good for the first autogyro.

Hope that helps.

Phil

My gyro project.
 

Phil

Thanks, that's a lot of good information.

Rich

Best Gyro to start with
 

Hi,

Me again. :rolleyes: My recommendation, as long as you are building the delta hubs would be to put one on a single rotor autogyro and install the Co-Pilot. (I know it's another $119.0) If the gyro is set up anywhere near right you are almost almost certain to get a good first flight. If you have a radio with an extra channel you can turn the Co-Pilot off and on while flying. Unfortuanately the Co-Pilot doesn't seem to work with a dual rotor. :confused:

Just another suggestion.

Phil

My gyro project.
 

Rich,

Skipp Ruff designed a great windmill when he released the FA-61. Your point about it having both a nosegear and a tailgear is important:

The best takeoffs you will get with the FA-61 is when you point the nose into the wind, patiently wait until the oncoming breeze tilts your FA-61 back onto the tailwheel...then smoothly throttle up (rudder effective at this point) and it rises off in cruise flight attitude (nose slightly above the horizon.) Then, when you allow the nosegear to finally touch after your flared landing, you can easily taxi back to the pits using nosegear steering. It's a good design, looks great and it proves to all (just like Phil P.'s twin-rotor designs), that they do not need an airfoil wing to fly!

Re: Best Gyro to start with
 

I may just do that. I have a 108 powered Spacewalker that wouldn't be to hard to put a rotor on top, and close in the wing opening. I don't know about the Co-Pilot, sounds good but I've got a girlfriend and a boat, I don't know which cost more! :confused: I don't want to get too many irons in the fire, I'd like to get the FA-61 done and take it to Indiana. It's real lucky my dad lives in Florida by the Gyro Flying in the winter, then goes home to Indianapolus in the summer.

Steve
Thanks for the info on flying the FA-61.

My gyro project.
 

Rich,

One thing for sure, the Spacewalker would sure look nice as as gyro.

I have a suggestion. Marry the girlfried and sell the boat and you will have plenty of money for an autogyro.

Phil

Re: Re: Best Gyro to start with
 

[QUOTE]Originally posted by soarrich
[B]

I may just do that. I have a 108 powered Spacewalker that wouldn't be to hard to put a rotor on top, and close in the wing opening.

Hi Rich...
Here's a comment from the "Frozen North"! <G>
The Spacewalker will require a fairly large diameter rotor. Experience seems to show that a disk loading of under 5 oz/sq. ft. will produce a flyable machine.

With large diameter rotors, the blades will have a tendency to flutter, unless the chordwise CG is forward of the center of lift of the blade. Steve recommends putting 1/8" steel wire imbedded in the blade as close to the leading edge as possible. Then mount the blade to the hub at about 30% of the chord. I have found a source of 1/8" dia lead wire that is pretty easy to handle too.

In any event I agree with Phil that a "SpaceWalker Gyro" will really be impressive!

Bill
Hudson, WI

Re: Re: Re: Best Gyro to start with
 

Bill

Care to share the source? Is it lead wire, not solder?

I just looked at my Excel speedsheet, the SpaceWalker is doable with one of my rotors for the FA-61, if I keep it under 10 pounds.

My gyro project.
 

Phil

I think I will buy a Co-Pilot. Who has the best price, or can you only get them direct?

I know sometimes it may seem as though I don't take advice well, I think it's just I do a lot of reseach, then do it my way with the iformation I've gathered. I think I've memerized Jim Baxter's webpage.

I've built maybe 60 planes, 5 where kits, 3 of them were for my wife and daughter, she was JR National Champion of all three sailplane classes '85. The 2 I built for me were a Sig Kadet MK I, which I built stock, and a Dodgson Windsong. When I spoke with Bob Dodgson a told him all the mods I had done his responce was, AAAAAAAAAAAnd it still flew? It flew great.

Co-Pilot
 

I'm not sure but I think you can only purchase them from FMA Direct. I just tried to buy another one and they are out of stock. Expect to have delivery in 2 weeks.

Phil

Re: Re: Re: Re: Best Gyro to start with
 

[QUOTE]Originally posted by soarrich

Bill

Care to share the source? Is it lead wire, not solder? [/B]

Rich....
I found lead wire at: http://www.corbins.com/lead.htm

Corbins is located in Oregon and supplies all sorts of materials for bullet and cartridge making. The smallest size wire is .105" As mentioned I bought a spool of 1/8" dia.

Bill

Re: Re: Re: Re: Re: Best Gyro to start with
 

[QUOTE]Originally posted by billf

Quote:

---

Originally posted by soarrich



Rich....
I found lead wire at: http://www.corbins.com/lead.htm

---

Bill
I saved the URL in case I need it to balance my blades. Thanks.

Phil

I just ordered the Co-Pilot system and a 24" cable. Is the cable between the senser on the Co-Pilot or the radio?

Didn't do any gyro work, other than the pictures, it's been too nice so I've been flyin' and sun'n.

My gyro project.
 

Hi Rich,

The cable goes between the external sensors which is mounted on the outside of the aricraft and the little computer where the servos plug in.

Phil