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Old Dec 22, 2012, 09:03 AM
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Mustang Fever
Joined Jan 2005
432 Posts
My Shrike with the 46AX has no roll issues on hand launch, as long as I let it go directly into the wind. Must be because it's turning 15000 + on the ground with a 10x6 prop, so there's not much torque. Also, it accelerates really quickly when I let it go. (Underhand toss, almost vertical.)

I do have this issue with my hand launched Outlaw, by Extreme Flight. It's electric (25 size) turning a 10x6 on 4S, around 11000 rpm, and is pretty torquey. One thing that helped a lot was I put a little over 1/2 oz of lead in the right wing tip. (Counter torque weighting described in that Model Aviation article a couple years ago.) I still bank it to the right a little before I let it go or it will roll left on release. The more into the wind I can get it on launch, the better it behaves. I experimented with a little right elevon trim on launch, but it didn't seem to help much. Right elevon takeoff trim does work with another of my deltas, tho, the "Bullet", my own design fuse with retractable gear using the wings from a Mikulasko "Arrow". However, if I have a long, smooth runway and can get up proper takeoff speed, she doesn't need it. (The issue with small, light airplanes that ROG is that they hit bumps and become airborne before there's enough airspeed to fly well.) That one also has counter torque weight in the wing tip.

I'm building a Dan Savage F-4 Phantom right now, 90mm EDF on 6s, and I'm thinking about putting some weight into the right wingtip. (Span is only 33", so it might be necessary.) I'm conflicted about it, tho, as half of my delta wing aircraft didn't like counter torque weighting at all, wanting to drop the right wing during flare for landing. (Two Laddie Mikulasko "Arrows", one glow, one electric.)

I built a Shrike 10 from the kit a long time ago, and powered it with an Astro 020 on a 2000 NiMh pack. It was turning a 5.5x4 at around 20000 and that was all too much for the airframe. Always had trouble getting sufficient airspeed for control before it would drop the left wing and auger in. It only flew a couple times before it got so decrepit I had to scrap it. Combination of too much torque and wing loading, I guess. Same airplane with a 2000 3S lipo would have flown great, I'll bet. I might try another one some day as the plans are available.

One thing I learned early on about hand launches- never have a neckstrap on the Tx. Mine got between my fingers and the stick right after launch (once)and I nearly crashed my beloved Sig Wonder.

Keep on Shrikin!
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Last edited by Bob Hunt; Dec 22, 2012 at 09:10 AM.
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