Aileron position question

 

As I complete my 40 hour Phase 1 test program, I have run out of things to do and measure, so it is time for tweaking. 

 

Has anyone done any testing of aileron position for optimal cruise? 

 

Droop, neutral, reflex up slightly, or ??? 

 

How much? 

 

Did you measure the effect of different positions, and can you report any data?

 

Cooling Drag Report

 

For those interested in cooling system drag reduction and curious about the effect of plenum, cowl flap and other mods, this is what testing has shown so far. 

 

Stock Lancair IV flat plate drag area: 2.12 square feet (as reported by Martin Hollman)

 

Moreno’s Lancair IV flat plate drag area: 2.01 square feet (three data points so far), nominal operation at 8500 feet, 65% power, cowl flaps closed, running 50F LOP  Note: you have to work hard to get repetitive data to within 1% which makes this measurement difficult.  It took lots of tries to get real consistency.

 

So the result of all that work is 1) about a 5% reduction in drag area compared to a theoretical best of maybe 7%, and 2) a VERY cool running engine, frequently under 300F, cruise climb, cowl flaps open, 310-330F at cruise 65% cowl flaps closed.  I am considering reducing the exit area a bit for a bit more SPEED.

 

Fred Moreno