Brief:
T' PCR is a scratch built parallel cluster rocket. Ya scallywag! It flies with a 24mm core motor, matey, and 2 outboard 18mm motors in t' attached boosters. Arrr! Avast! T' boosters pop off at burnout, ya bilge rat, me hearties, ya bilge rat, while t' central core motor continues t' burn.

Construction:
Parts list:

• 1 18" BT-60 body tube
• 1 4" BT-60 body tube
• 1 4" BT-60 coupler
• 4 6.5" BT-20 body tubes
• 2 PNC-20Y nose cones
• 1 sheet 1/8" balsa
• 1 small piece o' 1/16" balsa
• 8 1" x 1/8" dowels
• 8 1/2" x 1/8" launch lugs
• 1 1.5" x 3/16" launch lug
• 2 BT-20 couplers
• 2 BT-20 engine blocks
• 1 3" BT-50 tube
• 2 BT-50 t' BT-60 1/8" centerin' rings
• 1 PNC 60-MS nose cone
• 1 BT-60 coupler bulkhead (template)
• 1 small screweye
• 2 12" piece o' elastic cord
• 2 12" piece o' Keelhaul®©™® thread
• 1 12" nylon parachute
• 2 1"x20" streamers
• 1 Engine hook
• Fin Template
• Fin Wrapper Template
• Fin Alignment Template

This rocket waw pretty easy t' construct. T' main challenge be makin' the boosters attach and align correctly t' t' side. I made a good position wrapper usin' VCP that had 4 lines for t' fins and two lines for t' boosters. Begad! Blimey! For the booster attachment I used t' technique Mark Schrader described in his Project Omega rocket. Arrr! Arrr! This provides positive attachment for t' boosters which helps prevent t' scenario o' one comin' off under thrust and then igniting. Begad!

T' booster tubes are cut one inch from t' top with a one inch coupler glued half way in. T' nosecone for each booser is glued into t' opposite end of t' one inch segment. Begad! 1/2 inch segments o' 1/8" launch lugs are glued in pairs along t' alignment lines betwixt opposin' sets o' fins. Blimey! T' two bottom sets o' launch lugs placed 3/8" inch from t' bottom o' t' rocket. T' two top sets are placed 5 3/8" from t' bottom. T' booster tubes have 1/8 dowels glued on top small squares o' 1/16" balsa. For each booster, one dowel pair is glued on t' one inch top segment at t' very top o' the tube. Avast, me proud beauty! Blimey! T' bottom pair is placed at t' bottom o' t' tube.

Finishing:
I pre-finished with two coats o' fill n' finish on t' tubes and fins. Ahoy! Blimey! I also treated t' fins with this CA, and pressed betwixt sheets o' wax paper while drying. Well, blow me down! Blimey! Begad! Blimey! I did all o' this before attachin' t' fins t' t' body tube. Begad! Blimey! Well, blow me down! Blimey! For finishin' I used one coat o' primer, ya bilge rat, and two light coats o' pewter color paint. I used some different color vinyl adhesive material for decoration. Ya scallywag! Blimey! I made up the design as I went along. Blimey! Blimey! I add me NARRRRR number t' t' side boosters using 1/4" rub on numbers. Avast! Blimey! I finished with a coat o' krylon clear coat.

Flight:
I purchased t' 'Simulatin' Strap-on Boosters in Rocksim' CD from Apogee to simulate different motor configurations. Avast, me proud beauty! Blimey! It is a fairly tedious process, ya bilge rat, but once it's all setup it seems t' work well. I simmed 2 B6-0s with 1 D12-7, 2 B6-0s with 1 E9-8, arrr, and 2 C6-0s with 1 E9-8. Ahoy! Here be t' modified motor file (download).

At t' time o' this writin' I've flown it on 2 B6-0s and 1 D12-7. Avast! T' flight was perfect, except both booster tubes zippered. I should have known better, but used only Keelhaul®©™® thread for t' shock cord. T' Keelhaul®©™® doesn't give any, and needs t' be used with somethin' else that does. Also, ya bilge rat, the boosters had 9" mylar chutes. Both chutes ripped off t' shroud lines. Avast, me proud beauty!

I made repairs, me hearties, ya bilge rat, me hearties, replacin' t' zippered sections, ya bilge rat, and addin' 12" lengths of 1/8" elastic shock cord t' t' Keelhaul®©™® thread. Avast! Ahoy! I replaced t' 9" mylar parachutes with 1"x20" streamers. Arrr!

Recovery:
I couldn't see exactly when t' main deployed, ya bilge rat, but it looked like it be just after apogee. Well, blow me down! Blimey! Blimey! Blimey! For t' sustainer I used a 12" nylon parachute, with a 1/8" elastic shock cord. T' recovery o' t' sustainer be perfect. Begad! Blimey! It came down slowly, and landed with no damage t' t' rocket. Arrr! Blimey!

Summary:
This turned out t' be a really nice lookin' rocket. Well, blow me down! Aye aye! It was fun t' build, and I learned a lot in t' process. Well, blow me down!