Construction Rating: starstarstarstarstar_border
Flight Rating: starstarstarstar_borderstar_border
Overall Rating: starstarstarstarstar_border
Manufacturer: Art Applewhite Rockets

aaw_bumblebeeBrief:
This is one of the many new Applewhite monocopter designs recently introduced. Monocpoters, in general, are one of the strangest things you'll ever see fly and this one is reliable and easy to build.

Construction:
The parts were sealed in a plastic bag and included:

  • 3/32" basswood stock for support pieces
  • 3/32" basswood wing/blade (2x3)
  • 1/4" dowel balance beam
  • (2) 3/16" dowels for upports
  • BT-5 motor tube
  • Adhesive fiberglass reinforcement

Having previously jumped on the Helix which is about a 10-minute build, this one struck me as relatively more complex. This was still very easy and probably took a good 30 minutes.

First step in contruction is to cut out 3 different support pieces from the basswood using dimensions provided in the instructions (simple rectangles/no patterns necessary). The only one found a bit odd was the center piece which is not square but 0.75x0.80". 0.80? Maybe metric would have been better as my ruler goes to 32nds, not tenths.

This center piece is glued to a 0.5x1.25 support piece and the directions point out the importance of grain direction/orientation, as these pieces will go through a good deal of stress during flight. A couple small dowel supports flank the edges of the center piece.

The wing is already precut/sized, and mounts against the support piece below the center and is angled to run under one support dowel and then over the other. It's this slope that generates lift when the thing starts spinning like crazy.

The other brace part is then glued to the motor pod and this assembly goes onto the other side of the support dowels, angled exactly the opposite directin as the wing/blade.

The adhesive fiberglass "tape" (really more of a loose weave of about 1/8" spaces) is then wrapped around the motor tube and anchored to the support brace. A liberal coating of wood glue is in order to secure it.

The final step is to drill a 1/4" hole in the center brace which is used as the launch lug. You'll probaly want to go a little oversized on this so that is slides smoothly up and down a 1/4" bolt which is used instead of a rod. That proved to be the only problem I faced in construction, as my power was knocked out for a full week in the aftermath of hurricane Ike which wreaked havoc in the midwest after its nastiness along the Texas gulf coast. Lacking power for my drill, I wound up just using vice grips and a drill bit to slowly whittle away the hole by hand.

Finishing:
I chose not to decorate mine, flying it naked. I definitely would not recommend the weight of paint but possibly magic markers or dope for a litte coloring would be appropriate.

Construction Rating: 4 out of 5

Flight:
The recommended motors for this are the gamut of full A 13mm's and included the no-longer-NAR-certified A10-0 (minor whoopsie there unless the flyer is participating in the old motor testing program). I flew on an A3-4 hoping for the slightly longer burn versus the A10.

Having skipped the recommended construction of a special monocopter pad, I used a regular 1/4" rod but stuck a clothespin 1.5" from the top and slipped the Bumblebee onto it. Monocopters, when they fly right, are almost instantly stable once they get spinning. You definitely do not want to use a full length rod, doing so will simply result in pulling and whipping as it climbs the rod.

This flew perfectly on the A3, spinning incredibly fast. The apogee as barely 50 feet, as these are saucer-like flyers. With my Helix, the -4 delay was way too long. The model was on the ground when the ejection charge fired, risking a fire in dry conditions.

Recovery:
The Bumblebee retains the motor and begins to tumble after burnout. Recovery in the tall grass was gentle enough not to inflict any damage, though the motor tube showed signs of charring and weakening after just one flight. From what I've learned of delays, I suspect the charring was from the hotter flames of the delay burning than the thrust, so that would be another good reason to go with the shorter delay A10-3 or best bet the A10-PT's if you can still find them (most retailers are ditching them as they drop the rocket-powered race cars).

Flight Rating: 3 out of 5

Summary:
Overall, I am really loving monocopters and the Applewhite designs all seem to be easy to build, safe and reliable.

PROs: Unique flyer/recovery, easy to build

CONs: Compared to Helix, this is a bit more work to build and not much better/worse a flyer, plus the motor tube charring could be a problem (though I didn't see the whole tube on the Helix since it's partially hidden).

Overall Rating: 4 out of 5

 

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