flap/aileron likage: Radiator position/cooling ducts: Kevlar; lightning strikes


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Feb 25, 2005
Near Euroa, Central Victoria, Australia
G'day Guys,
I'd like to tap in to some of the wisdom on this great site if that's OK.
We are about to start a 4-place version of Steve Rahn's "Vision", & would appreciate advice in the following areas.

1/. Can anyone describe a flap & aileron linkage which will do the following:- lower slotted flaps AND ailerons together to 10 & 20deg., then flaps ONLY to 30 & 40deg. while (slotted), ailerons stay drooped at 20deg.
Also flaps AND ailerons to reflex 5 & 10deg. together.

I believe there was a STOL conversion for Cessna singles which did this but I have never seen any linkage drawings. Also, two aircraft in 1937, the Airspeed A.S. 39 & the General Aircraft G.A.L. 39 "Feet Shadower", used this system, stalled below 35kts & cruised at 38!!. Lift Coefficient was ~3.5.
I have drawn up a few "sytems" but none of them very elegant,- any suggestions?. Is it "on" to mount one bell-crank on another?. Flutter?

2/.Any thoughts on the optimum position for a liquid cooled radiator & associated inlet & outlet? My view at this stage is to mount the largest area possible radiator (i.e. thinnest core), in the rear fuselage, the smallest possible inlet with an expanding duct & a reducing duct to an appropriate area outlet. I have read that the inlet area can be as low as 25-30% of the radiator area if the inlet duct is at least 2.5 times as long as the max. radiator dimension,- comments?. Similarly I have read that the outlet area should be 78% of the inlet area,- ????.

3/.To save weight could Kevlar Style 500 be directly substituted for Style 7725 Bidirectional e-glass as called up in the plans?. (Would you believe NO information is available from DuPont (Australia)!!!). I saw photos of Kevlar gliders built in a U.S. College in Jack Lambie's book "Composites in Homebuilt Aircraft". All Aussie "experts" & academics advise against it but mainly due to it's user unfriendliness.

4/. How big an issue is lightning strike to composite aircraft & what safegaurds can be built in?.

Hoping I haven't outlived my welcome,
Cheers from malbo downunder.