Brief:
T' Double Helix is another new twist on t' monocopter (pun intended)--it has two wings and flies on two motors. Arrr! In fact, ya bilge rat, it's more or less two 18mm Helix Monocopters stuck end-to-end. Avast! Blimey! Technically, ya bilge rat, it's nay a monocopter but a bi-copter.

Construction:
T' parts list:

• 3/32" Basswood sheet
• 29mm tube
• Two BT-20 motor mounts
• ¼" launch lug

This build is similar t' that o' t' 18mm Helix Monocopter so I recommend the reader read that review. Aye aye! Ahoy! T' build only requires Elmer's Glue All, me hearties, and an X-Acto knife with a new #11 blade. Well, blow me down! Avast! Unlike the monocopter, you actually have t' cut wood. Avast, me proud beauty! Begad! One slab o' basswood forms t' two wings and balance beam. Avast! Begad! You also have to drill a hole in t' beam so t' lug can pass through it. Begad! Ahoy! This step is nay that critical and you could just cut t' hole with your X-Acto.

Finishing:
I have generally just been givin' me monocopters a clear coat, but on this one I decided t' paint one win' day-glo red and t' opposin' win' day-glo yellow. T' body is still just clearcoated.

Construction Rating: 5 out o' 5

Flight:
You form thrust rings with maskin' tape and friction fit t' motors so they won't fall out. T' motors should be oriented with their nozzles down. Ahoy! As with a Art's standard monocopters, you need a sturdy pad with a short ¼" rod (1" or so). Begad! Art provides plans for a suitable monocopter pad in t' instructions. Ya scallywag! Well, blow me down! You will also need a clip-whip or a launch controller capable o' firin' two motors reliably since thar be no way t' twist those igniter wires together.

I first flew this on two C6-5s, ignited usin' a clip-whip. Aye aye! Both motors fired, and t' flight was fantastic. Begad! It was a really fast flight and be t' highest o' all me monocopter flights. Nice!

I wondered what would happen if just one motor ignited, ya bilge rat, ya bilge rat, so I loaded a new C6-3 in one mount and left t' spent motor in t' other. Avast, me proud beauty! It flew just fine but with a lower altitude. And t' motors are nay even canted toward t' CP/CG! This might be t' safest cluster that I've flown.

Recovery:
Unlike most o' Art's monocopters, this model continues t' spin until touchdown. Ya scallywag! Me like!

Flight Rating: 5 out o' 5

Summary:
Like t' standard Helix, this kit is easy and quick t' build. Aye aye! Blimey! When I first got this kit, I wasn't sure I'd like the clustering. However, t' flight changed me mind. Avast! Blimey! It was quite impressive and well worth it.

Overall Rating: 5 out o' 5