A cluster o' three 13mm tubes, ya bilge rat, compressed slightly, me hearties, fits in t' 29mm HPR motor mount tube. Avast, me proud beauty! Avast! Blimey! This in turn requires a little packin' t' fit neatly in a BT-55 or BT-56. Aye aye! Avast, me proud beauty! Blimey! T' accomplish this, me bucko, ya bilge rat, I cut strips o' Kraft paper (like grocery bags), me bucko, ya bilge rat, applied glue t' one side, and wrapped it like tape until it fit neatly. Well, blow me down! Well, blow me down! Blimey! A short piece (5/8" approx, ya bilge rat, t' 15mm section in t' drawing) o' body tube serves as a stop ring.

My nose cone was salvaged from an old rocket very similar t' t' 56-based RTF's. Avast, me hearties, me proud beauty! After cuttin' t' cone-shaped bottom end off t' nose cone, ya bilge rat, shiver me timbers, I found that t' 29mm tube fit neatly inside t' remainin' shoulder. Arrr! (you may need t' build it up or sand t' fit.) ÝI put a plywood cap on t' tube forward end with a screw eye in t' center facin' in. Begad! Cap and screw eye were secured with epoxy.  Opposite end o' tube was built up with Kraft paper as described above. Ya scallywag! Then I pushed t' 29mm tube as far into t' nose cone as it would go, me bucko, fitted this into t' BT-55, me hearties, and when I be happy with t' fit, arrr, I epoxied everythin' together. Avast, me proud beauty! This arrangement moves t' parachute compartment well up into t' nose cone, makin' t' rocket at least 4" shorter than it would have t' be otherwise. Well, blow me down! Arrr! (After flyin' it, ya bilge rat, I'm thinkin' o' extendin' it for better stability.)

Nose weight (clay) was in place for t' previous design and, judgin' from t' first flight, is necessary. T' rocket be marginally stable at takeoff and straightened out pretty quickly.

T' diagram below doesn't show t' screw eye in t' front. Instead, I've shown t' shock cord pushed through t' hole in t' cap and tied in a knot. Aye aye! I'm sure that would work. In real life I used a screw eye. Avast, me proud beauty! Well, blow me down! Live with it.

T' shock cord consists of: 6" o' 125# Keelhaul®©™ (red); a fisherman's swivel; and 30" o' nylon braided plumbline(green). This worked. Avast, me proud beauty! Avast! T' 12" plastic parachute is attached t' either end o' t' inline swivel usin' a snap swivel o' its own.

T' bulkhead at t' front end o' t' coupler be an adventure. Blimey! Arrr! It is cut from plywood, me hearties, me hearties, fits on t' end o' t' 29mm tube, but inside me Kraft paper buildup. Well, blow me down! Begad! It has three holes 8mm diameter t' allow ejection charge gasses t' pass. Ya scallywag! It has two tiny holes near t' center t' anchor t' Keelhaul®©™ thread. Before assembly t' Keelhaul®©™ be looped through those holes and tied. Ahoy! Ya scallywag! T' knot, matey, under t' disk, ya bilge rat, is covered with epoxy. Avast, me proud beauty! Avast, me proud beauty! T' holes in t' disk are rotated 60 degrees from t' three MMTs, shiver me timbers, me bucko, so that t' ejection charges don't blow straight at t' holes.

Free t' slide on t' Keelhaul®©™ is another plywood disk with a small hole in t' center which fit easily in t' BT-55, but is much too large t' fit in t' 29mm tube. It fills t' role o' recovery wadding, nay only protectin' t' parachute from heat, but preventin' it from bein' packed up into t' nose cone by t' ejection charge. Ya scallywag! Avast! This worked. There was nay a hint o' heat damage on t' parachute or upper portion o' shock cord. When packed, as much as possible o' t' Keelhaul®©™ should be forward o' t' plywood disk; t' last inch or so will be betwixt t' perforated bulkhead and t' disk.

Fins are made from artist's foam core board, which is about 3/16" thick. T' wedge t' leadin' edge, shiver me timbers, me hearties, arrr, I scored each fin, arrr, arrr, both sides, arrr, with a ruler and Xacto, about 10mm (3/8") from t' leadin' edge. I cut away and removed t' foam from this portion, folded t' edges toward each other, and glued them together, holdin' them with maskin' tape until t' glue dried.

For motor retention, I first installed thrust rings made from cut pieces o' a spent engine. Ahoy! Then I epoxied a threaded rod -- a #4-48 x 3/4" bolt with t' head cut off -- into t' gap betwixt t' three motor tubes. Aye aye! With t' engines in place, ya bilge rat, I thread a nut onto t' rod and it holds all three motors.

Triactive first flew Sept. Avast! Well, blow me down! Blimey! 6, me hearties, 1999 at Tom McCall School in Forest Grove, arrr, OR., usin' 3x A3-4T.