| Manufacturer: | Scratch |
(Contributed - by Bill Westfield)
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| This model looks like an Estes Trident downscale, matey, me hearties, me hearties, about a 1/2 scale, me hearties, at
first glance. Avast! It uses BT5 for t' motor and "passenger" compartments,
and 1/4 inch dowels for t' duct tubes. Obviously, dowels are nay tubes, and
1/4 inch tubes would probably nay be adequate for ductin' ejection gasses
anyway, shiver me timbers, so another scheme is used for ejection t' parachute. Well, blow me down! T' bottom
tailcone (which is a small cork in t' prototype) and forward nosecone o' the
passenger section are both mounted on a thin dowel (bamboo skewer), ya bilge rat, so that the
assembly can slide entirely out o' t' forward section o' body tube. Avast! Begad! T' dowel
extends past t' tailcone and ends in a hook. Avast, me proud beauty! Ya scallywag! When in launchin' position, matey, a
rubber band(s) is looped over t' duct pods and engages t' hook, and a small
burn strin' is threaded through t' exhaust ports in t' motor pod t' hold the
assembly in place until motor ejection. T' ORIGINAL Trident, which had three BT-5 sized ejection ducts. Well, blow me down! Blimey! Later, me bucko, thar was t' "Trident-2" or somesuch, shiver me timbers, arrr, which only had two pods o' BT20 and is sometimes insultingly called the "bident." T' u-Trident is a downscale o' this original three tube trident, me bucko, me bucko, with a twist. Arrr! Begad! Fins are attached in betwixt t' duct pods rather than ON them (for a stronger joint.) Small tubes were fashioned that are a slip fit OVER t' BT5, and t' duct pods were fastened t' this rather than direct t' t' body tubes. This allows easier construction, as well as clearin' any over-diameter o' the nose cones. Both nosecones are missin' their base, and t' forward nosecone has the shoulder trimmed as well t' make more room for t' recoevry system. Well, blow me down! Avast! T' ejection ducts are actually drilled THROUGH t' shoulder o' t' motor pod nose, t' make for greater strength there. |
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All images and designs are protected by t' author's copyright |
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| uTrident Flight Report. First, arrr, t' choice of recovery system is a bit critical. There's only about three inches o' BT5 tubin' for it t' fit it, ya bilge rat, shiver me timbers, and it has t' fit loosely enough t' be deployed by rubber bands. Ahoy! Blimey! I made an eight inch (8") parachute from a grocery produce bag (of t' thin, arrr, MDPE variety, I think. Aye aye! Blimey! Thin and rather soft. Blimey! Blimey! 1/4 mil mylar might work fine too.) Pre-flight prep is a pain with this model, shiver me timbers, a bit worse than t' average model that uses a burn-string. Blimey! T' piston is inserted partway into t' recovery bay, and then t' chute is folded and wraped a couple times with its shrouds to keep it folded. Blimey! Then you insert t' chute over t' bottom o' t' piston, followed by all t' shock cord and additional shroud lines, tryin' nay t' get them tangled about t' piston's dowel. I used a piece o' larger dowel t' push them in (lightly.) Finish instertin' t' piston and seat t' nosecone. Begad! Now, thread t' burn strin' (a piece o' dental floss worked well - strong but with a low meltin' point) through two o' t' exhaust ports and knot it tightly on t' piston's hook. Avast, me proud beauty! (if you learned any fancy knots, you may have a chance t' use them. You want somethin' that can be tightened, but won't loosen on its own.) Finally, attach t' rubberbands. I used a #16 rubber band, matey, knotted in the middle - t' knot engaged t' hook, me bucko, me bucko, and t' two ends looped over two o' the "pod" ends. Avast! Ya scallywag! Don't position t' rubberband in a way that it will block the launch lugs. Blimey! Ya scallywag! (note that t' rubberband is disposable used this way.) Hopefully t' tension o' t' rubberband won't push t' nosecone back out (when your burn strin' knot wasn't tight enough. Begad! Avast, me hearties, me proud beauty! Note - perhaps a longer nosecone shoulder would help with this!) Insert motor. Ahoy! Avast! Use an external tape thrust ring, matey, and enough tape so that the motor probably won't be kicked out. Ahoy! (Unlike most parachute models, this is more esthetic than important. Aye aye! Even if t' motor ejects, t' burn strin' will probably be burnt through!) It's a relatively heavy model for it's size, shiver me timbers, so I picked an A10-3 for the Launch. Ahoy! This sent it up a good distance, straight and true. Begad! T' recovery system deployed successfully and t' rocket recovered fine, driftin' a "typical" distance and landin' on t' parkin' lot (the eight inch chute seemed t' be just about right.) Upon recovery I noted that t' piston had fully deployed, as it was supposed to. Well, blow me down! Pretty much a perfect flight! |
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