It's a stock Integral with a counter rotating drive swinging a pair of 22 X 18 handmade (by Mike Gaishin ...) carbon fiber props. The motor is a stock Hacker C50-14XL.
I started working on the design back in November of last year, and with the help of Mike and Andy Gaishin of Gaishin Manufacturing doing all of the fabrication, I've finally got it in the air.
I first flew it last Thursday for three quick flights, and I got another three quick flights in on Saturday afternoon after the Jimmy Hubbard Memorial Contest in Chicago. All during those six flights I was trying to get the right mixes in for knife edge, and downlines, but I was still struggling with my vertical uplines. They seemed okay, but the plane wasn't locked in like I'm used to with my Integral.
So last night I added 0.5 degrees of down thrust and flew it again this evening, and it was like throwing a switch. All of a sudden it was absolutely perfect! The uplines are now locked in like the plane is climbing a ladder and the downlines are plumb line straight.
I am absolutely over the moon. Right now it's flying exactly like I hoped it would fly but better because it seems there are additional benefits that I didn't anticipate.
A point by point summary of flight performance is as follows:
1/.. The double prop setup generates a huge braking effect when the throttle is at idle, so the plane flies at the same speed regardless of whether it's climbing vertically up, dropping vertically down, doing an eight point roll, or flying over the top of an avalanche.
2/.. This constant speed characteristic makes snap rolls much easier to do, because the plane always snaps in exactly the same way, with exactly the same roll rate.
3/.. For some reason, I had to cut my rudder travel by more than 30% because it was way too sensitive. I haven't figured this one out yet.
4/.. The rolling performance is considerably improved over my other Integral, (even though that rolling performance was pretty good to begin with ...) and requires almost no rudder to maintain altitude. This is going to significantly improve my half reverse cuban with 2 of 2, my eight point roll, and my 2 of 2 reversed.
5/.. Stall turns are much easier and more predictable because now it's possible to let the plane slow down until it just hangs on the prop and then pinwheel it around with rudder without having the wings twist out of plane. This makes it much easier to do a perfect figure M.
6/.. The motor braking effect lets me do a perfect spin entry even without any headwind.
7/.. The motor braking effect also means that I need to fly it in under power when I'm landing, even with no headwind. Fortunately deadsticks are rare with electric.
8/.. Takeoffs are much easier, because there are no motor torque effects that need correcting. Now I can take off at full power and fly out perfectly straight.
9/.. Loop tracking is the same right side up as inverted. Now all I use the rudder for is to gently nudge the plane either to the left or right. At no time do I have to hold any constant stick pressure.
I checked the noise at 9 ft, and I measured 92db. On the ground it doesn't sound much different from my hacker C50-14XL with a 21X14 APC prop, but as soon as it leaves the ground you can hear a syncopating rhythm as the prop blades pass each other. It doesn't sound loud, just different.
Right now I am using about 3000 mah for the current AMA Masters pattern. If this holds up for windy days, I might consider switching from the 5350 mah packs that I use now to 4350 mah packs. |
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发表于 2012-6-15 11:32
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