Okay, big news! Buddy Wieder, Tom Hampshire and I flew the testbed twin this morning!
Good stuff for sure and a few very minor glitches: First the good stuff. The motors ran perfectly throughout all 10 flights this morning. We flew a couple of one minute flights to be certain that everything was adjusted properly, and then flew some 4 minute flights. Trust me, you will not want to arm wrestle with Buddy and me after next year's season...
It was neat to be able to trim the amount of degree tangent to the circle that the airplane flew with the adjustable pot on the timer. We made the inboard motor run just about 100 rpm's faster than the outboard motor. We may be able to dial that back a bit since we have more than adequate line tension. Just wanted to be safe for the first few flights...
The wings are not yet perfectly level and I suspect that I may have a curl in the outboard flap. The flaps are raw 1-pound foam covered with .2 ounce/sq.yd. carbon, attached with thinned Titebond. They are a bit too flexible I think and I'm going to retrofit genuine balsa sheeted units.
The ship turns dead equal in both directions, grooved like a freight train, and is extremely easy to fly through maneuvers. It tracks beautifully through rounds, and it turns and locks on target for the legs of the squares, The bottoms are flat and predictable. It really flies like a great stunt trainer!
The only problems encountered was with the timer - which is an experimental/beta test unit from Will Hubin. It ran the motors perfectly, but when the 5-second drop in RPM occurred, the motors kept on running for a full minute instead of for just five more seconds as usual. That's just a minor programming issue for Will, I'm sure. There was also a programming glitch in the retract timer; I could not set it to extend the gear past the 59 second mark. Again, just a minor thing and I'm confident that Will will quickly remedy that. For obvious reasons we did not experiment with the retracts this morning...
All in all it was a fantastic session. Buddy and I each flew several flights with the ship and we are very encouraged by the results.
The 9 x 6 APC props are turning just over 10,000 RPM, and the rotation is set to have the tips of the props turning towards the canopy. We will, of course, explore all the possible prop rotation options as we proceed. We'll also try larger props. We can go all the way to 11-inch props! Of course then my arm will just pull clean off and fall to the ground...
After a 4-minute flight I just put nominally 1400mAh back into the 4S 3300 mAh Hyperion packs. We should be able to fly complete 5 minute and 45 second flights, operating the gear up and down, and still be safely under the 80 percent rule!
It's been a long time coming, and I appreciate everyone's patience and interest in this project. With a bit more testing we are confident that our "real" twin ships will be successes.
Later - Bob