Yesterday I went by our local electric hobby shop and discovered he had just received a shipment of E-tec cells. He had a tray of 250s; so, based on your current Li-Poly configuration and our conversations, I bought three of them and will make a three cell series pack.

From : Don Stackhouse

Just remember to use the 3-cell pack with the twin motor system, but with the small prop. The thing we've found about the MPS-2( ) is that it doesn't like to be over-propped, the motors like to be able to wind up. OTOH, at your 7000' altitude the 6-5 prop might be just fine. Check your current at full throttle, it should be about 1.3 to 1.5 amps with the correct prop. Please let us know what you find.

Also, be sure to rig about 1/8" total of right aileron into the plane when the rudder is centered, you'll need it to counteract the torque. If you don't, you'll run out of aileron trim, AND your plane will fly crabbed to the right. The ailerons on the Triplane aren't all that effective, but the rudder is very powerful, at least in flight. However, there is almost no dihedral effect, yawing the plane has almost no effect on roll. The full-scale Triplane had these same characteristics. The model does some of the best hammerheads of any model I've flown, just pull the nose up, boot the rudder and she whips right around, then stops immediately with just a slight jab of opposite rudder. I can do a hammerhead with the one I'm flying now from just above stall speed, with about a 3' altitude loss on the recovery, with economy cruise power. With practice it could really scare the daylights out of any combat opponent foolish enough to try to get on your tail (just don't wait till they get too close, you could have a head-on midair!!!). You could probably hammerhead right in front of them, hit full throttle as you dip under them on the recovery, then immediately do another one just behind them to end up on their tail. If you were really proficient, it could also be an effective "wall-avoidance maneuver" when flying in a gym.

I hadn't thought of batteries in terms of watt-hours of energy...It makes sense. I'll test the Dr.I MPS-2A configuration with the Kokams first (as I already have them mounted and wired--two on each side of the fuselage under the mid wing with wiring going through two small holes in the fuselage), then I'll disconnect them and fly the E-tec 250s. Because they are a three cell pack, did you mount them as a "block" of three or did you split them two/one on either side of the fuselage for balance?

Don Stackhouse
DJ Aerotech