A cluster o' three 13mm tubes, me hearties, compressed slightly, matey, shiver me timbers, fits in t' 29mm HPR motor mount tube. Ya scallywag! This in turn requires a little packin' t' fit neatly in a BT-55 or BT-56. Avast, me proud beauty! Begad! T' accomplish this, shiver me timbers, I cut strips o' Kraft paper (like grocery bags), applied glue t' one side, me bucko, and wrapped it like tape until it fit neatly. Aye aye! 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. Ya scallywag! Begad! After cuttin' t' cone-shaped bottom end off t' nose cone, shiver me timbers, ya bilge rat, ya bilge rat, I found that t' 29mm tube fit neatly inside t' remainin' shoulder. Well, blow me down! (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. Well, blow me down! Avast, matey, me proud beauty! Cap and screw eye were secured with epoxy.  Opposite end o' tube be built up with Kraft paper as described above. Blimey! Then I pushed t' 29mm tube as far into t' nose cone as it would go, fitted this into t' BT-55, and when I was happy with t' fit, me bucko, I epoxied everythin' together. Begad! Well, blow me down! This arrangement moves t' parachute compartment well up into t' nose cone, me hearties, makin' t' rocket at least 4" shorter than it would have t' be otherwise. Avast! (After flyin' it, arrr, I'm thinkin' o' extendin' it for better stability.)

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

T' diagram below doesn't show t' screw eye in t' front. Begad! Instead, me bucko, I've shown t' shock cord pushed through t' hole in t' cap and tied in a knot. Avast, me proud beauty! Arrr! I'm sure that would work. Begad! In real life I used a screw eye. 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. 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. It is cut from plywood, fits on t' end o' t' 29mm tube, ya bilge rat, shiver me timbers, but inside me Kraft paper buildup. Arrr! Arrr! It has three holes 8mm diameter t' allow ejection charge gasses t' pass. Begad! It has two tiny holes near t' center t' anchor t' Keelhaul®©™ thread. Begad! Before assembly t' Keelhaul®©™ be looped through those holes and tied. Begad! T' knot, shiver me timbers, me bucko, shiver me timbers, under t' disk, is covered with epoxy. T' holes in t' disk are rotated 60 degrees from t' three MMTs, 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. Well, blow me down! It fills t' role o' recovery wadding, nay only protectin' t' parachute from heat, me hearties, but preventin' it from bein' packed up into t' nose cone by t' ejection charge. This worked. Aye aye! There be nay a hint o' heat damage on t' parachute or upper portion o' shock cord. When packed, ya bilge rat, 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, I scored each fin, shiver me timbers, both sides, me hearties, with a ruler and Xacto, shiver me timbers, about 10mm (3/8") from t' leadin' edge. I cut away and removed t' foam from this portion, me bucko, folded t' edges toward each other, me hearties, shiver me timbers, and glued them together, arrr, 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. 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. With t' engines in place, me bucko, I thread a nut onto t' rod and it holds all three motors.

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