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Old 09-05-2002 | 01:47 AM
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bgi
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From: Duluth, GA
Default Lift-off with no flaps?

Paul,

This is the ARF. If I replace this with another Knife, I'll probably get the kit. It would be much easier to get the servos installed with a kit. Now that I've built the ARF once, I "get it", but installing the servo rails to be removable while lining the servos up with the covers was a major PITA! A Kit will give me a chance to use a more visible scheme, as well. The ARF isn't bad, but if the sun is in your face, it can be tough to tell up from down.

Gator,

You said it! I'm building a couple scale planes, a 4-star 60, and a big Edge. But I'm a profile fun-fly maniac now!


David,

About the Knife lift-off problems:

I was using low rates per the manual.
Engine: TT .46 Pro with standard muffler
Prop: APC 12.25x3.75 fun fly
Fuel: 10/18 synthetic with 2% castor added (really 10/20)
95 degrees (hot)
The engine has about 2 tanks through it and so wasn't quite leaned out.

This engine/prop combo will climb out of a hover.

I did a 10 or 20 foot roll before trying to lift up. I gave it FULL UP with 30% flap mix and it barely lifted off. It was pretty anemic about it. With that prop, it accelerates very quickly!

After that flight, one of our best pilots explained to me that it wouldn't lift off without flap mix unless I bent the landing gear in to raise the nose. He ran one down a 300 foot asphault runway (no flap mix) and it would NOT take off! Other folks in our club who fly Su-do-khois have the LG pressed in so that the wheels are barely separated. Perhaps they didn't mix flaps in, either?

Obviously your experience is different. What's the trick? Is your tail wheel holding your plane's tail up as high as mine is? When mine sits on the LG, it has a shallow AOA. Tell me about your take-offs. What's the AOA with it sitting on the ground?
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