I am trying to find out what kind of experience people have had with autogyros without the horizontal tail surface.

The Japanese Wallis does not any horizontal tail surface

Go to the following link and select TOPICS:

http://www2.ttcn.ne.jp/~rad/htmeng/e-open.htm

Thanks

Wahid

I believe size is an important consideration, as well as rotor mass.
The smaller/faster/lighter the rotor the faster it responds to
input either, pilot or gust. Once the rotor responds faster than
the pilot it becomes unflyable/unstable. Most people can balance
a 5 foot broomstick in their hand, but if you shrink the proportions
down to a #2 pencil vitually no-one can balance it. Rotor response
scales the same way.

There are a substantial
number of larger 2 bladed rotor craft with no horiz surface. As you
get smaller and smaller you either need stabilizing aerodynamic surfaces
like a horizontal tail or you artificially stabilize the rotor with a flybar or tip weight.
My choice was flybar just to see if I could do it in the scale I was working with.
My long term goal is to try a tip weighted flybarless version of what I have, after
I become proficient with gyro flight.
I notice that most gyros use head tilt to create cyclic control, this being a elegant
mechanism. I chose a swashplate because of the very light control forces needed.
When the head has any kind of offset to the flapping hinge this creates very high
forces back to the servos, I could't afford the larger servos with the electric.
Sorry about the rambly answer, I guess my final answer is that if you can get the
rotor stable the whole aircraft is stable therefore you can omit the horiz surface that makes up
for the rotor instability.

RAD models also produces the Kirara. The head looks the same exept it obviously has direct elevator control built in. Looks like the same blades and same head. I would say that if it weighs less than 4.5 lbs it would fly well with that configuration. Check out my post in this forum on "my shiney new Kirara gyrocopter". I Imagine it would fly very similar to the Kirara, asuming the weight is the same.

Looking at their site it doesn't look like they kit this model but I will ask my LHS guy in Tokyo if he can find it.