Brief:
When I first saw Matthew McFarland's Whirlygig in FlisKits' Deuce bash Contest, I immediately knew I had t' build one. Avast, me proud beauty! This is a 24mm version o' this odd, helicopter design. Ahoy! Since thar be little theory t' help determine stability (how do you swin' test this anyway?), shiver me timbers, me bucko, me bucko, I built mine out of leftovers. As a result, t' design is nay optimized. Begad! Arrr! It is heavier and chunkier than it probably has t' be. Aye aye! I am providin' this t' show t' overall dimensions that seem t' result in a stable model. Well, blow me down! Well, me hearties, blow me down! If you build one with another form factor, ya bilge rat, arrr, please launch safely! Note I used an oversize lug so I could fly from the high power pads. Aye aye! Well, blow me down! I invite you t' read more about Whirlygigs and ask your questions on t' Yahoo OddRocs group.

Construction:
T' parts list:

• Mailin' tube, me hearties, 2" x 22"
• 24mm tube, 4.125"
• 24mm PNC, type unknown, matey, 2.5"
• ¼" balsa fin stock (2 pieces, me hearties, matey, 3" x 7")
• ¼" launch lug, ya bilge rat, ya bilge rat, 2.25"

Buildin' this rocket was easy. I first found t' center o' t' tube and marked centerlines on t' top and bottom. Ya scallywag! Ahoy! I then located t' fins based on these centerlines. Begad! Avast, me proud beauty! My fins are approximately 120 degrees apart and are inset one inch from t' end o' t' tube. Avast! T' lug was mounted in a notch next t' the motor tube. Ya scallywag! I used epoxy for t' cone, motor tube, and launch lug. Aye aye! Begad! Wood glue was used for t' fins. T' fins extend all t' way across t' tube, shiver me timbers, leavin' a 5" x 3" surface exposed. Aye aye! T' motor tube extends below t' body tube by 3/8".

Finishing:
T' tube I used be speckled with paint from a previous project and t' nose cone was green. Avast, me proud beauty! That's all t' finishin' it got for its maiden voyage. Arrr! Begad! I later filled t' balsa and painted t' rocket half black and half fluorescent orange.

Flight:
I have flown me 'Gig 4 times, once on a D12-0, twice on E9-Ps and once on an Ellis F20. I added a tape thrust rin' and friction fit t' motor lightly. The first flight was on t' D12 and I didn't know what t' expect. Begad! T' boost was straight and had a slow rotation. Avast! Arrr! It didn't go high enough t' begin spinnin' on the way down. Arrr! T' E9 flights go much higher, and it attained enough altitude to begin spinnin' on t' way down. Avast! T' F20 flight, me hearties, me bucko, needless t' say, me hearties, was faster and even higher. Well, shiver me timbers, blow me down! Oddly enough, t' 'Gigs do nay seem t' rotate while on t' rod, so I don't know how much t' spinnin' has t' do with stability. Avast, me proud beauty! This effect is not easy t' see on t' F20, arrr, but is clear on t' smaller motors.

T' launch photo is courtesy o' Vertical Force Rocketry.

Summary:
This is a fun rocket and is sure t' get everyone's attention. Well, blow me down! I built another version that used Nike-style fin cans in place o' t' balsa. Avast, me proud beauty! All I can say is make sure you have enough fin area. Ya scallywag! That version be nay stable!