
(Contributed - by Dick Stafford
- 05/22/08)

Brief:
The Whirlwind Monocopter is the 18mm Dragonfly's bigger brother and flies on 24mm motors. I had the opportunity to
build and test a beta version, which was known as the Cyclone. The differences between the beta and production models
are minimal.
Construction:
Wing: Basswood, 2" x 10" long
Balance Beam: Long dowel
Center, Center & Motor Supports: Basswood and short dowels
Motor Mount Tube: BT-50 tubing
Motor reinforcement: Fiberglass drywall tape
The construction of this kit was simple and similar to the
Art Applewhite 18mm
Dragonfly. The following materials and tools are required: Elmer's Glue-All, hobby knife, scissors, ruler, drill
with 1/4" bit. I substituted carpenter's glue for the Elmer's.
Here's a summary of the steps:
- Assemble center hub
- Add supports and balance beam
- Glue wing on
- Assemble motor mount, including fiberglass tape wrap
- Glue mount to hub
- Drill launch rod hole
At the end of each step, heavy fillets are applied to all joints.
Finishing:
Finishing is optional but at least a clear coat is recommended. I used Helmsman Spar Urethane.
Construction Rating:
5
out of 5
Flight:
Prep consists of centering the motor in the mount, adding a tape thrust ring, and friction fitting. You can use
booster motors or sustainer motors with short delays. It flew off of my standard pad, which happens to be similar to
that described by Art (plans included in the instructions and on his website). I already had a 1/4" stubby
monocopter rod. I flew mine twice on a D12-P and an E9-4. The D12 flight was nice, but the longer burn E9 was
fantastic! The winds were heavy and they did travel a ways downrange, but the walks were short when compared to any
rocket with anything that resembled a chute.
Recovery:
At burn-out, the monocopter flutters lightly to the ground. I found that the side of the E9 had burned through just
above the nozzle. Because of the length of the motor vs the motor tube, this did not damage the model. It may have
reduced the performance toward the end of the burn.
I did not reduce my rating due to the burn through. This is unavoidable and, like I said, there was no ill
effects.
Flight Rating:
5
out of 5
Summary:
Not much to say. Simple, elegant build and lots of fun to fly. Get some E9s!
Overall Rating:
5
out of 5
Other:
Soaking the self-adhesive tape in glue tends to make it lift. I used plastic clamps to hold the tape down at the
joint between the motor tube and its stand-off. Plastic clamps won't stick to the glue and may be removed after the
glue is partially set.