I was looking through an old Futaba manual and it had a section on programming the limit switches for variable pitch props. Talks about "air braking", and not needing an idle speed.

There was one available back in the early/mid '80s.
I saw Steve Helms use one at the World Championships in Pensacola in 1983.
There were some issues with them shedding blades.
For that reason the one Helms used was not available to the public.
That about all I know which isn't much...
As usual![sm=bananahead.gif]
JLK

I'm pretty sure both Prettner and Wolfgang Matt experimented with them in the late 70's - early 80's... That was one of the reasons Hanno designed the simple, boxy Calypso to win the WC in 83, his feeling was that F3A was getting too complex equipment wise.

Low Rider,
I saw Hanno at the '83 Worlds as well.
He didn't have a variable prop.
He did want to show the pattern world that you didn't have to have a complex plane to win.
The empennage was all flat plate and it was a simple design.
However, for braking in the down lines he had an intermediate landing gear position.
They would be kinda half in, half out.
He had gear doors oriented 90 degrees from normal so that they in effect acted as air brakes.
The best individual flight I saw that year though was by Ivan Christiansen (sp?).
It was as near perfect as I have ever seen.
Simply beautiful...
JLK

I think Graupner made one called the vario-pitch. Prettner had one on his Magic. A few others (Matt, Helms even Dave Brown) tried them. Reliability was the biggest limiting factor! Plus the weight of the mechanism and an extra servo.

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Matt's "Magic" was designed around using the variable pitch prop, IIRC.

The one that Steve Helms used was produced by MK. He threw alot of blades at first. You ought to see what losing a blade does to an airplane! Problem he had was to try to run it at the current rpm's back in those days. Once the rpm's came down, the prop became more reliable. I saw him fly it many times and never thought it was worth all the hassle.
Greg Grigsby

Very interesting! Thanks! Always seems what's new is old. Re: the current crop of variable props for the electric crowd.

I ran the mk setup for one season. when apc props came out, their performance was so much better than anything else that I never ran the variable set up again.

I had one on a Curare and it worked OK for the time. it did not have beta pitch available as I recall ( 11/0-8 or so) but could go flat pitch for down lines. It worked but really was not worth the effort at the time. Now that we have computer radios and you could do a p-mix with the prop, it might be interesting.
Gordie