Raven (kitfox 2/3 clone) to gyroplane

[knuckled62]

I am in the process of converting this airframe to a gyroplane like the "littlewing" by Ron Herron.
I need help to decide what size/weight engine i can hang on this Fuselage.
I am trying to determine which model this is a copy of, i will include a couple of pictures of the airframe.
It looks like a combination of an Avid Flyer/kitfox 3 and is primarily constructed 1/2 4130 except the wing spar carry tubes and the two main cross tubes in the floor.
I plan on changing the front spar tubes to 1" X .048 and the forward down tubes too 5/8' X .048 tubing.
according to Ron i will need 100hp for reasonable performance and am leaning toward a 110hp corvair conversion but it is 225 lbs and i want to make sure fuselage will carry that weight.

I am hoping that some of the more experienced/knowledgeable people will chime in

[avidflyer]

The shape of the door bottom, and the lift strut attachment point say a Kitfox 1 to me. Is it 36" wide at the center/back of the door? Later Kitfoxs are 39 1/2" there. Jim Chuk

[Av8r3400]

The Raven was it's own airplane. Kind of a mashup of an Avid B/C and Kitfox 1/2. Never the less, a 225# engine will be way, way too heavy for that airframe, IMO. It was designed around a 75# 582.

Since you are not making an airplane but a gyro out of this, I really can't offer much advise other than in the fixed wing configuration that engine would need a load of ballast weight in the tail in order for it to balance properly.

Good luck. Post some photos of the conversion.

[knuckled62]

At this point the only thing i have done is cut down tail and remove all non structural tubing, ie flight controls, landing gear bungie attachment points ect.

I am looking at all power plant options, would prefer 4 stroke but cant afford new rotax or D-motor, the corvair has the right power and is affordable but is heavy.

I knew i would have to reinforce certain parts of airframe for engine and mast mount.

The mast is adjustable for and aft to account for different weight power plants.

I might have to go to the point of building mast mount and using ballast to see if i can get weight and balance to work.

really what i was trying to find out was if the structure on the plane would be capable of handing that weight on the front, i will work out weight and balance.

thanks

[knuckled62]

It is 35" wide at back door.

I had an opportunity to measure a kitfox 4 1200 gross weight, i don't recall if i measured across the cabin, but all forward structure was basically identical.

[avidflyer]

The fuselage dimentions I gave were for outside to outside. Here is a Kitfox 4 fuselage I hauled home several years ago. (Maybe some day I'll finish it) Lots of changes from a Kitfox 1 that aren't apperent at first glance. Width (at top of seat) is just one of them. Jim Chuk