Have you guys ever electrified a 2M Chrysalis? Do you have info on what to use and how?

I am still flying a 2M Chrysalis but because of my time constraints have come to enjoy electric sailplanes very much. My time off tends to come in 1 hr or less duration, and high starts/winches just take too long.

From : Don Stackhouse

Yes, we've had one flying for a couple years now, with excellent results. The only reason it isn't in production yet is because my old computer couldn't handle those instructions. I barely survived getting the sailplane instructions plotted, and I just couldn't face going through that again with my old 486/66. I just recently upgraded to something that can handle those enormous drawing files, so if I can now manage to get some of the other projects on my schedule caught up, I'm going to try to get the electric 2-M Chrysalis done.

However, if you don't want to wait (which, judging from my schedule, would probably be a wise move), it isn't too difficult for a moderately experienced modeller to convert the sailplane version. I'd suggest callling Joe and ordering a fuselage/tail kit. From F2 aft, the electric version is identical to the sailplane version, other than the radio installation. Servos go just in front of F3, with the receiver just in front of them. The battery goes on the C/G, using the remaining space under the wing behind F2. This allows for a variety of battery sizes without running into C/G problems. The ESC goes in front of F2, behind the motor. The ESC uses the throttle channel. I usually put the spoilers on the landing gear channel, so they only operate as fully open and fully closed. On a 6 or 7 channel radio you can of course put them on one of the channels with sliders.

If you plan to do long thermalling flights, I strongly recommend using a non-BEC speed controller and using a small separate battery (sized based on the length of flights you're planning for, just like with any normal sailplane) to power the radio. BEC controllers shut down the power to the motor when they sense that the main battery is getting low enough that there's just enough juice to power the radio long enough for landing. If you're soaring at 1500 feet with the motor shut off, you won't have time to get down safely. OTOH, if you are going to do contest work with a specified flight time length and max motor run time, a single battery for both motor and radio should be OK.

For sport flying, we've had good results with a Speed 600 motor running a direct-drive Graupner 8-4.5 folding prop on 7 cells. 500 mah cells work OK for a single climb, but for general sport flying I usually use a 7-cell 1400 or 2006 mah pack. It takes about 5 clicks of the throttle stick above idle cutoff to sustain level flight, and on the 2006 mah pack I typically get in excess of 24 minutes of continuously powered flight WITHOUT using thermals.

If you want much more spirited climbs and longer flight times under power, and don't mind the extra complexity and expense, use about a 3:1 gearbox and about a 14" prop.

The nose mods include shortening the front ends of the fuselage sides by 3.5" (89mm), bevelled for 5 degrees down thrust. The right one should be shortened a bit more than the left to provide 2 degrees right thrust. With that much down thrust, the aft end of the motor will be sticking up above the top edges of the fuselage sides, so you'll have to hollow out the underside of the hatch and nose cover in that area to clear it. On the production version we make the fuselage sides higher in that area to fix the problem. You'll need to make a firewall mount from about 1/8" (3.2mm) plywood to fit your motor. Use 1/2" (12.7mm) balsa triangle stock about 1.25" long in the corners of the nose to allow you to sand the corners sufficiently round at the front to match the spinner. A little glass on the outside of the nose after you've sanded it to shape would be a good idea. That's about all there is to it!

Good luck, and don't hesitate to ask if you have any additional questions!

Don Stackhouse
DJ Aerotech