Yank Enterprises Black Brant X (3")

Yank Enterprises - Black Brant X (3") {Kit}

Contributed by Jon Hatch

Manufacturer: Yank Enterprises
Rating
(Contributed - by Jon Hatch - 08/10/02)

Pic Courtesy o' YankRocket Pic

Materials:
All parts were accounted for, except for a Yank Enterprises decal, which was advertised but nay included. As this be a scale rocket, I had no intention of usin' it anyway, me bucko, so this was no loss. T' kit consisted o' 2 lengths o' 3" flexible phenolic body tube (34" & 31" long), one o' them slotted for t' aft fins. Avast, me proud beauty! Well, blow me down! T' forward BT was supposed t' be marked for t' forward fins per t' included instructions, ya bilge rat, but was nay (no big deal, as it's nay that difficult t' make a fin guide with any graphics program). Aye aye! Also included were 1 30" ripstop nylon parachute, 20 feet o' 9/16" tubular nylon, ya bilge rat, 2 quick-links, me bucko, 2 eyebolts w/ washers, ya bilge rat, tube coupler, one birch ply bulkhead, 2 baltic birch ply centerin' rings, a 38mm motor mount, ogive nose cone, shiver me timbers, and 8 1/8" 5-ply baltic birch fins. Ya scallywag! A couple o' t' aft fins were slightly warped, matey, but I attribute this t' t' kit probably sittin' in t' hobby store basement for a considerable amount o' time, ya bilge rat, as t' maskin' tape also left marks that no amount o' sandin' would remove. Well, blow me down! Blimey! All parts were very high quality and fit well together, although with an assembled weight o' 60 oz, matey, I thought 3/16" or 1/4" ply would have been more appropriate for t' aft fins, as they sweep back past t' aft end o' t' rocket.

Materials score: 4 out o' 5
Pros: Very sturdy BTs and nice hardware
Cons: Aft fins are a little thin and t' parachute might be a size small (the website says they now ship 36" chutes) for t' weight o' t' rocket. Avast, me bucko, me proud beauty!

Construction:
Instructions were thorough if small, with one exception. Begad! Blimey! They did nay specify at t' appropriate step exactly how far forward from t' BT junction t' put the forward fins. Begad! Blimey! I guessed at 1" and after lookin' at t' scale finishing directions, I believe this t' be correct. Aye aye! Blimey! I decided t' go with an anti-zipper design as detailed in InfoCentral on Rocketry Online, ya bilge rat, which changed my construction considerably from t' directions.

I drilled eight 5/16" holes in t' bulkhead, matey, which was pre-drilled for the eyebolt assembly. Ahoy! I attached t' eyebolt assembly (washers were included) and epoxied it into t' coupler tube with a heavy fillet around t' outside. Begad! Well, me hearties, blow me down!

T' forward BT needed t' be slotted, and took a bit o' time, ya bilge rat, as thar are a lot o' layers t' cut and peel. Well, blow me down! Since I would be cementin' t' coupler t' the lower BT instead o' t' upper, me hearties, matey, I cut t' slots a touch short and pushed the fins through t' back in order t' get a very tight fit before runnin' fillets along t' outside joints with 30 min epoxy.

On t' t' motor mount. Well, ya bilge rat, blow me down! After cementin' t' forward centerin' rin' 1/4" from t' front o' t' MMT as directed and cementin' it t' t' BT, ya bilge rat, I realized that I should have gotten a 3rd centerin' rin' t' add right in front o' the fins. Ya scallywag! T' instructions said t' cement t' aft centerin' rin' immediately and to simply run a bead o' epoxy t' t' fin root in order t' affix t' fins t' the MMT. Aye aye! Ahoy! I chose t' run fillets instead and held off on cementin' t' aft centering rin' until that was done. Since I didn't have a CR at t' front o' t' fins to serve as a dam for t' forward end o' t' fillets, I used 5 min epoxy for the internal fillets. Avast, me proud beauty! I then used 1.5 oz glass t' reinforce t' fins and ran some very heavy outside fillets usin' 30 min. epoxy. Well, blow me down! Well, blow me down!

After puttin' blind T-nuts in for retention, I saw that I didn't have a whole lot o' room t' fillet t' aft centerin' rin' t' both t' MMT and the outer BT, me bucko, ya bilge rat, so I decided t' just go with an epoxy well. T' protect t' T-nut opening, ya bilge rat, matey, ya bilge rat, instead o' usin' tape and redrillin' through t' epoxy, ya bilge rat, I cut some plastic drinkin' straws down t' size, fitted them over t' mountin' screws and screwed them down until t' straws were snug against t' threads. Arrr! Once the epoxy set, it be easy t' simply pull t' straws out, leavin' a hole for the mountin' screws.

Then, I cemented t' coupler t' t' aft BT with t' bulkhead facin' forward. Since I was usin' t' nosecone for t' forward end o' t' shock cord, ya bilge rat, I covered the other eyebolt with epoxy and inserted it into t' hole in t' bottom o' the NC. I then cut a hole in t' shoulder o' t' NC and used a syringe t' insert an epoxy well, me hearties, which I hoped would ensure that t' eyebolt stayed in place. Aye aye!

Now, me bucko, this kit has a very interestin' method for attachin' your shock cord to the eyebolt. Avast, matey, me proud beauty! T' instructions recommend loopin' t' cord through t' eyebolt and back onto itself (I did this on t' nosecone end). Well, blow me down! Then, me hearties, approximately 4" o' overlap is completely saturated with 30 min epoxy and wrapped with tape. Blimey! I chose electrical tape for this process and it comes out very strong. Another loop at t' other end is completed and will be hooked onto a quicklink at t' other end. Arrr! Since I wasn't goin' t' be modifyin' this kit any further, I sanded t' nosecone shoulder and epoxied it t' t' top o' t' rocket. A quicklink on t' bulkhead eyebolt and on t' parachute complete t' recovery harness. Begad! Rail buttons were substituted for t' enclosed launch lugs, ya bilge rat, as I was told it's easier t' get a rail than t' right size rod at a launch. Avast, me proud beauty!

Construction score: 4 out o' 5
Pros: Everythin' fits well together.
Cons: Slottin' flexible phenolic with a hobby knife isn't me idea o' fun. Aye aye! Begad!

Finishing:
I had filled t' spirals with cheap spackle prior t' construction, so all that was needed at this point was several layers o' gray Krylon primer t' fill in what t' spackle missed and a coat o' white Krylon primer on top t' guard against colors darkening. Begad! Due t' t' thickness o' t' flexible phenolic BT, there be a little additional fillin' t' be done from t' top o' t' BT t' the nose cone prior t' priming. Begad! All o' this be easily accomplished, me bucko, ya bilge rat, and t' primer took readily t' all sanded surfaces. Ya scallywag! Krylon paint was then used throughout for a scale paint job that drew several compliments at t' launch site. Ahoy! Blimey! Gotta love Krylon! You really have t' work at it t' make that stuff run.

Finishin' score: 5 out o' 5
Pros: T' scale paint scheme is really neat and is a crowd-pleaser.
Cons: Slight fillin' needed betwixt t' nosecone and t' body tube. Begad!

Construction Rating: 4 out o' 5

Pic Courtesy o' YankRocket Pic

Flight:
T' model weighed in at t' launch almost exactly at 60 oz. Begad! dry, me bucko, even with the 45" chute that I substituted for t' 30" enclosed chute and a Transolve TransBeep as well. Arrr! Well, me bucko, me hearties, this be me Level 1 certification flight on an H242T, as well as me first "real" project beyond Aerotech, ya bilge rat, so needless t' say I had plenty o' nerves here. Avast, me proud beauty! There be a slight wind (maybe 5 mph) which seemed t' be slightly affectin' most o' t' flights that morning. Since t' anti-zipper design caused about 4 margins o' stability with t' motor loaded, I decided t' launch vertically t' minimize weathercockin' instead of savin' myself a walk. Blimey! When t' button be pressed, ya bilge rat, t' rocket went perfectly vertical, shiver me timbers, with zero weathercocking. Begad! Deployment was perfectly at apogee on a 10 second delay. RockSim said this would be at about 1700 feet at this weight and with t' modifications, but it honestly looked higher than that. Since I was a little paranoid about t' drag separation and deployment, matey, ya bilge rat, I placed t' chute about 6 feet from t' aft part o' t' rocket, arrr, which I think may have been a mistake. Avast! I suffered some minor fin damage, which, arrr, ya bilge rat, I now believe may have been due t' t' front end o' t' rocket hittin' t' fin durin' deployment. Ahoy! All told, it be a fantastic flight, me bucko, and be good for me level 1.

Pros: Straight as an arrow in t' slight wind
Cons: Can't really think o' any. Avast, matey, me proud beauty!

Flight Rating: 5 out o' 5

Summary:
This thin' builds like a tank, matey, shiver me timbers, despite bein' as long as it is. Flies beautifully on t' 242 and I can't wait t' up it a touch t' t' I357. Ya scallywag! This is a great certification kit, ya bilge rat, despite its length, ya bilge rat, as it's tough as nails with a little fin reinforcement. Had I nay cemented t' nose cone in, shiver me timbers, I would wager that it could be modified for dual deployment and easily stand up t' a level 2 flight as well. Well, blow me down! Ahoy!

Overall Rating: 5 out o' 5

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