This is build #35 of the Model Airplane Building Clinic
sponsored by Murcoflyer. Please checkout the other builds by going to the base/start thread.
I have never had or built a glider before. So this will be new for me. Any and all comments and pointers are not only welcome, but encouraged! I’ve also sent a message to Don Stackhouse who’s the designer of the Chrysalis and part owner of DJAerotech to see if he can follow along and give me some tips. He’s active over on RCGroups, hopefully he can come to WattFlyer as well.
Here's the specs from the DJAerotech website.
Chrysalis 2M Electric Sailplane by DJAerotech
Wingspan: 78.5" (2.0 meters)
Wing Area: 723 square inches
Fuselage Length: 47.6" (1.21 meters)
Wing Loading: 7.37 oz./sq.ft. (Li-poly battery)
9.44 oz./sq.ft. (nicad battery)
Weight: (outrunner motor, 14-9.5 prop, separate 270 mah 4-cell NiMH radio battery)
37 ounces w/ 2-cell 2000 mah Li-poly motor battery
47.4 ounces with 7-cell RC2000 nicad motor battery
The Chrysalis was originally designed for a Speed 600 and NiCad batteries. I’m planning to go brushless and use some of my LiPos I already have. So here is my current plan… If anyone else has some good ideas, please chime in!
My Goal is to have a lightweight plane that can accept many different batteries to adjust the final weight. That way I can go very light for when there is almost no wind, but heavier for windier days. I also do not have a lot of storage room, so I’m thinking of the three piece wing option. It would be great to end up with the plane weighing about 30 ozs without the battery.
I’m thinking of using a lightweight brushless motor in the 250 Watt range. This is about where the 480 sized motors are and you can find both 35-xx and 28-xx sized motors in this power range. The included firewall is made for a square 25 mm bolt pattern and a rear mount motor. So far I am thinking that the HeadsUpRc Firepower 480 would be a good fit.
It’s a 260 Watt, 35-30 motor with a 25mm x 19mm bolt pattern. It should fit the included firewall with just creating two new holes. Since this motor weighs only 2.6 oz, I’m planning to stretch the nose by 1.5 to 1.75 inches as well. I have read about others doing that with good success. If I can keep the plane balancing neutral with the motor, then the batteries can still sit under the wing like in the original design.
The plane can optionally use either a conventional or V-tail setup. I’ve read that the V-tail is slightly lighter, so I’m planning on going that way. I also like the looks of a V-Tail better, so it’s a easy decision.
In Summary here’s what I’m planning.
Chrysalis 2M Electric Sailplane with 3piece wing and V-Tail options.
Stretch the nose by 1.75 inches.
Reuse the following components that I already have:
Spektrum AR500 receiver
32 Amp ESC (Powerup from HeadsUpRc)
1.5 in Folding Prop Spinner for a 4mm shaft.
10x6 Folding Prop
Covering from Hobbypartz. (Trans Purple, White and Black?)
Purchase the rest of the needed components:
2 9gm servos (V-Tail)
2 5 gm servos (Spoilers)
Servo Y cable (For Spoilers)
250 (or so) watt blushless motor
Folding Props/Spinner as needed for the Motor selected
Building will be slow for a while, but I thought I'd get started!