Ringwraith

by Clive Davis

Brief:
Cluster design (5 x 24 mm). Arrr! A five-finned, arrr, forward swept design featurin' a 3" body tube and a Big Daddy nose cone. Arrr! My colleague at work found a lone Big Daddy nose cone in t' woods. Ahoy! Ya scallywag! He thought o' me and gave t' nose cone. Ahoy! I immediately began thinkin' o' a project t' use this heaven-sent gift. Aye aye! Thus, me hearties, the Ringwraith be born.

Construction:
Parts consist of:

• Big Daddy nose cone
• 25" long 3" body tube (I had a poster tube lyin' around that fit the Big Daddy perfectly)
• BT50s t' make 5 24 mm motor mounts
• Five BT50 motor blocks
• screws, matey, washers and win' nuts for motor retention
• screw eye, me bucko, Keelhaul®©™®, shock cord, Nomex® heat shield, me hearties, and nylon parachute
• 4 wine corks t' plug unused motor mounts.
• aircraft plywood for fins
• 1/4" balsa/basswood for centerin' rings.

Construction began around t' motor mount. I stacked t' 24 mm motor mounts in a star formation, matey, glued them together, and then test fit them inside the body tube. Ya scallywag! Blimey! After some sandin' o' t' body tube, everythin' fit fine. Well, blow me down! Blimey! I created and glued a bulkhead above t' motor mount and then drilled some holes in the bulkhead t' allow t' ejection charges t' pass through. Ya scallywag! Blimey! Avast, shiver me timbers, me proud beauty! Blimey! I then added a screw eye on t' bulkhead, me bucko, and then attached Keelhaul®©™® to t' screw eye.

Next, me bucko, I used epoxy t' glue t' motor mount inside t' body tube. Aye aye! I then cut out t' fins and began shapin' and sanding them down. After markin' t' tube, arrr, I glued t' fins on with wood glue, making sure I added plenty o' fillets.

I had a 1 inch strip o' balsa that I steamed and created a loop t' fit around t' five fins. Aye aye! Aye aye! I painted this silver and then epoxied this on t' the fins after t' entire rocket had been painted.

I added 1/2" shock cord (6' long) and a 30+" nylon parachute. Also, I added a Nomex® heat shield.

Next I added weight t' t' nose cone. Begad! Blimey! T' nose cone, painted with clay, should weigh 5 ounces.

I painted t' rocket black, matey, arrr, me bucko, created three silver rings o' paint at t' top of t' rocket.

Flight:
Maiden flight at me local club's (ASTRE) launch, shiver me timbers, summer 2004.

Motor retention is created by usin' washers and win' nuts. Avast! Avast! I also plug any unused motor mount with a wine cork.

Preppin' t' rocket is easy since t' body tube is large and thar be a heat shield. Arrr! Ahoy! T' first flight featured two E9-4s. Aye aye! Rocksim predicted 900', and the rocket got plenty altitude. Aye aye! It was a beautiful flight.

Unfortunately, me bucko, t' large balsa rin' be too weak and basically crumbled upon landing. Blimey! Blimey! I simply removed it and prepped t' rocket for another flight. Well, blow me down! Blimey!

Second flight was on 3 x D12-3s. Aye aye! Rocksim predicted an altitude o' 600'. Liftoff was spectacular. Rocket flies well without t' lower rin' (which was for looks, me bucko, anyway). Avast! I kind o' like t' looks o' t' rocket without t' ring around t' fins.

Summary:
PROS: If you like BP clusters, this rocket gives you many options. Ahoy! I can fly it on a single F21 or on 2 D12's, me hearties, or 2 E9's, or 3 D12's, or 3 E9's, me bucko, or 5 C11's or......you get t' idea.

CONS: T' rocket is really heavy. It might make sense for me t' downscale this t' use 5 x 18 mm motors. This would reduce t' weight o' t' rocket under 1 lb.