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Old 05-08-2007 | 02:58 AM
  #1634  
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From: Tokoroa, , NEW ZEALAND
Default RE: Nitro models pusher Bobcat?

I flew mine on the weekend (ASP (Magnum) 52 with 10x7 prop) and it flew about how I figured it would except...

On takeoff (after lifting off) it wants to climb very steeply, needing about 1/3 down elevator to stop it going vertical. This isn't the "leap off the deck syndrome).

The faster it flies (at full throttle) the more it wants to tuck it's nose down though. If I do a high-speed run I have to use increasing back-pressure on the stick to keep it level -- but once it slows down it starts to climb agressively again.

I'm wondering if it's that lifting tail section providing an increasing amount of lift (thus pitching the nose down) as the airspeed goes up.

Right now it's quite manageable but not a characteristic I enjoy. My CG is about 10.25 inches and it needs a good dose of down elevator to stay straight and level when inverted (indicating to me that the CG could/should go back further).

Did anyone else use the straight piece of wire when fitting the wing? The instructions on mine made no mention of this wire and although the position of the holes for it were marked on the fuselage they were not drilled. I drilled them and fitted the wire because I wanted to have the option of removing the wings rather than gluing them on -- although I'm reconsidering that.

I switched to a 10x8 prop today and noticed absolutely no difference in performance. The RPMs dropped slightly but the speed was identical.

The ASP is pulling (by ear) about 14,000-14,500RPMs with the 10x7 and I'm going to fit an OPS pipe. That ought to liven it up a bit :-)

What I am impressed with is the weight -- it's really light and you can slow it *right* up on the approach for very nose-high touchdowns. However, I've noticed that the elevator isn't too powerful in the turns -- another indicator that perhaps the CG is a little too far forward for my liking.

Just a few more data points.