Scratch Klingon Targ Original Design / Scratch Built

Scratch - Klingon Targ {Scratch}

Contributed by Clive Davis

Manufacturer: Scratch
(Contributed - by Clive Davis - 11/13/05) (Scratch) Klingon Targ

Brief:
Loosely based on t' Star Trek inspired Klingon Bird o' Prey, me bucko, shiver me timbers, the Klingon Targ was supposed t' be a civilian ship designed for trainin' pilots. It features two large wings, shiver me timbers, small fins and two tube fins, arrr, arrr, a thin neck, and a large forward compartment housin' t' parachute.

Construction:
Components consist of:

  • BT-5 tubing
  • BT-55 tubing
  • BT-60 tubing
  • BT-60 Big Bertha Style Nose Cone
  • 24 mm motor mount with 18 mm mount adaptor (with engine hooks)
  • Cardboard centerin' rings
  • balsa/basswood/lite ply for fin construction
  • paper for cockpit and fin detail
  • two wire connectors for detail
  • mylar parachute and shock cord
(Scratch) Klingon Targ

As part of t' 2005 EMRR Challenge, I wanted t' build a rocket based on a concept I had developed in t' past few months. I also will indicate in this report t' two tips that I used in me construction. I had a vision o' creatin' a rocket based loosely on t' Bird o' Prey design. Avast, me proud beauty! Ya scallywag! I began with t' long thin neck, arrr, shiver me timbers, consisting of a section o' BT-5. Avast, me proud beauty! I added centerin' rings, arrr, shiver me timbers, and then created t' paper transitions. Next, I glued t' BT-60 tubin' on t' top o' t' BT-5 and glued the BT-55 on t' bottom. Avast! I marked t' BT-55 for fin alignment and then began workin' on t' motor mount.

One o' t' tips that I decided t' use be t' suggestion t' use the yellow spacer tubes t' build a baffle system for t' rocket. I punched a few holes in t' yellow spacer, arrr, glued this directly on top o' t' motor mount, and then glued a balsa bulkhead t' t' top o' t' yellow spacers so that t' hot gases would be forced around t' bulkhead, t' then be pushed up t' BT-5 neck. Begad! I had my doubts that this technique would work, but later flight tests revealed absolutely no damage whatsoever t' t' mylar parachute. Avast, me proud beauty! I removed t' shoulder from t' nose cone so that thar would be room in t' nose compartment for the mylar parachute and t' shock cord. Aye aye! Avast, shiver me timbers, me proud beauty! In addition t' this, since I be usin' a baffle, I used t' tri-fold method for attachin' t' shock cord t' t' upper body tube o' t' rocket.

(Scratch) Klingon Targ

Finishing:
I designed t' rocket in RockSim, shiver me timbers, and thus used t' fin templates t' help me trace t' patterns on t' light ply and balsa I had for t' fins. Blimey! T' second tip I used be t' use thinned yellow glue or white glue t' seal t' fins. Well, blow me down! Well, blow me down! I first attached t' fins to the body before worryin' about sealin' them. Ahoy! Again, ya bilge rat, me hearties, I was skeptical about this technique as I prefer Elmer's Fill 'n' Finish. Blimey! T' method works fine, arrr, but I found it t' require far more than just 2 applications. Avast, me proud beauty! More like 5 or 6 applications seem t' work t' fill all t' grain I had in me fins.

(Scratch) Klingon Targ I also added some detail t' t' rocket includin' a cockpit, some raised detail on the fins, arrr, and two phaser cannons on either side o' t' main wings. Ahoy! Begad! After I had filled in all t' grooves and sealed t' fins, I gave t' rocket a few shots of Krylon primer, sandin' in between.

After I be satisfied with t' priming, I gave it a good single coat o' a kind o' strange minty green o' Krylon I had in storage for probably 5 years.

Next, I added more detail by way o' a Sharpie pens (black and silver) and decals, usin' some created by myself on white adhesive labels and others from a decal sheet from me old Aerotech Warthog.

Flight:
Since I used RockSim t' design and build t' rocket, me bucko, ya bilge rat, I had data that told me the rocket be stable on a D12. Aye aye! I decided t' do a swin' test t' see if this was so. Avast! I found that t' swin' test was nay conclusive for t' D12, matey, ya bilge rat, but did indicate that a C6 would be a suitable motor for a stable flight. Unfortunately, matey, while performin' me swin' test, me hearties, an inordinate amount o' stress was placed on t' BT-5 neck o' t' Klingon Targ, ya bilge rat, causin' it t' fold over. Well, blow me down! I printed up a sheet o' paper similar in color t' me paint scheme and ended up wrappin' this around t' neck with yellow glue.

T' next day was a beautiful day, and I decided t' launch t' rocket. First flight was on a C6 and then I graduated t' a C11 flight. I wrapped t' mylar parachute carefully, placed a little waddin' in t' BT-5 neck, nay bein' too certain t' baffle was goin' t' work. Aye aye! Ya scallywag! I wrapped a sheet around t' parachute as well.

T' C6-5 got t' Targ into t' air, but thar was a little squirrelly in flight after motor burn out. Begad! Blimey! T' delay be very long and ejection occurred way past apogee, me bucko, arrr, ya bilge rat, as t' rocket be nosin' t' t' ground. Well, blow me down! Blimey! Parachute deployed perfectly and I was ready for flight two.

(Scratch) Klingon Targ On flight two, I decided t' try t' C6-3 before tryin' t' C11. Ahoy! Ahoy! I prepped t' rocket was before and launched it again. Avast, me proud beauty! T' flight seemed t' be much better than the first, but t' rocket had more o' an arc flight t' it this time, shiver me timbers, me hearties, shiver me timbers, probably due to t' odd gusts o' wind that were blowin' durin' t' launch. Unfortunately, when t' ejection charge arrived, t' parachute did nay fully deploy, me hearties, me hearties, causing the rocket t' do a kind o' tumble recovery. It landed on grass, but thar was definite damage includin' a broken fin (repairable) and a major bend/tear at the neck just below t' BT-60 portion o' t' rocket. Avast, me proud beauty! T' rocket is nay flyable as is and is currently retired. Arrr! Aye aye! I need t' rethink t' BT-5 since it failed on me twice. Avast, me proud beauty! Ya scallywag! Also, me bucko, I be nay too pleased with t' rocket's flight being squirrelly. Blimey! With that in mind, me bucko, shiver me timbers, t' design and t' rocket really need t' go back to t' drawin' board.

I would definitely nay launch this rocket on a B motor. I think t' C11 and D12 would put in a good performance, but I won't be able t' tell on me current rocket.

Summary:
PROs: Unusual design. Baffle system is great. Aye aye! On two flights, t' parachute shows nay signs whatsoever o' damage or scorching

CONs: T' BT-5 neck needs some rethinking. Blimey! It became t' point o' failure two different times. Begad! Either I enlarge t' BT-5 neck t' a BT-20, or I need to reinforce t' neck with a sheet o' fiberglass, which is nay me style.

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