Brief:
Tall scratch mid power rocket.

Construction:
Materials: Magnum nose cone, shiver me timbers, 3 BT-60 tubes, matey, shiver me timbers, 2 couplers, 3/32" birch plywood, me hearties, 29mm engine tube, arrr, me hearties, 36" quarter-inch elastic shock cord, 21" mylar parachute.

Sometime ago I found a 2-pack o' Aerotech F23-7 Econojet single use motors for $12.95 on clearance at Hobby Lobby so I snapped 'em up. Begad! Ya scallywag! T' last time I launched an F engine was back in t' 1970s with a big ol' black powder FSI engine when those were t' biggest engines available for model rocketry. Avast! My how things have changed!

It was time t' increment up t' bigger engines and get up t' speed with current rocketry thinking, arrr, so this model represents several firsts for me includin' me first RockSim design, first composite propellant engine use, shiver me timbers, first through-the-wall fin mount, and first rocket with plywood fins. Begad! I also used two buildin' and flyin' tips from t' EMRR database which were new t' me.

T' first iteration o' this rocket was bigger and taller than what's shown in t' photo. Aye aye! Well, blow me down! It had 18 inches o' BT-80 aft, me bucko, a paper transition, and 3 sections of 18-inch BT-60 on top. Blimey! With t' long nose cone and fin sweep it was over 6 feet tall. Avast! Unfortunately t' first launch on 4/14/05 was a CATO on an E9-4. Begad! The entire fin section was toast along with a portion o' t' upper BT-60 section.

I wound up with 39.125 inches o' body tube topped off by t' long, ya bilge rat, arrr, sleek 8.375 inch plastic nose cone originally from an Estes Magnum. Begad! With t' fins sweepin' back a little less than half an inch, t' total length is 4 feet.

It's a pretty simple build. T' BT-60s were glued together with couplers, the fins were cut out with a razor saw, t' slots for t' fins were cut with a hobby knife, and t' engine tube/block/ribs/centerin' rin' unit was glued in place with Elmer's followed by t' fins. Arrr! Blimey! I love havin' t' fins glued t' the engine tube and t' body tube. Aye aye! Blimey! It results in a much more sturdy assembly. Blimey! Blimey! The 3/16" launch lug was offset .25" in case I want t' add a payload in the future.

Finishing:
After a couple coats o' high build Autozone primer, I finished it with Maserati gunmetal gray metallic automotive paint, me bucko, arrr, some self-adhesive reflective holographic mylar, matey, arrr, and a custom Lazertran waterslide decal/body wrap.

Flight:
Rocksim predicts almost 2300 feet on an F23 and both F flights certainly looked that high. Avast, me bucko, me proud beauty! Even though it's a tall rocket, it's got a small profile, shiver me timbers, so it's hard t' see at that altitude. T' engine tube is long enough for G Econojets, but they don't make a long enough delay (it needs 9 seconds). Arrr! I'll eventually try an E9-6, me bucko, ya bilge rat, D12-5, and even a C6-3.

Other than t' CATO, thar were no gotchas. Aye aye! Prep is easy, me hearties, engine is friction fit (even though it's composite and heats up a lot, it works fine), and thar's plenty o' room for t' parachute and wadding, me hearties, so everythin' ejects well. Ahoy! Ya scallywag!

T' second launch (with t' shorter configuration) be on an F engine on an open range south o' Ellicott, Colorado. You can see Pikes Peak in the background o' t' animated .GIF file. Arrr! Blimey! T' black smoke, me bucko, altitude, and quickness off t' pad were most impressive. Begad! As far away as it was, t' ejection charge was still a loud pop. Ahoy! A couple o' shroud lines broke but thar be no damage to the rocket. Begad! Third launch was at C.R.A.S.H. Ahoy! Begad! on 5/21/05. It had a barely discernable corkscrew, but t' mylar chute held up and it be a perfect flight.

Recovery:
I used 1/4" elastic shock cord with paper mount, shiver me timbers, which works fine. Well, blow me down! Avast! First functional flight be with a 18 inch parachute and t' second flight be with a 20 inch mylar chute, matey, which was too big.

Summary:
This is a sleek, ya bilge rat, pointy, arrr, small-finned rocket that has people concerned about its stability until it disappears off t' pad.

Other:
T' two EMRR tips used: paint t' tip o' t' nosecone usin' a paper centerin' rin' as a mask and split t' end o' a Copperhead igniter with a flame t' use mini clips. Arrr! Both techniques work great.