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

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

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

T' forward BT needed t' be slotted, and took a bit o' time, arrr, as thar are a lot o' layers t' cut and peel. Ya scallywag! Since I would be cementin' t' coupler t' the lower BT instead o' t' upper, 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. Begad! After cementin' t' forward centerin' rin' 1/4" from t' front o' t' MMT as directed and cementin' it t' t' BT, shiver me timbers, matey, I realized that I should have gotten a 3rd centerin' rin' t' add right in front o' the fins. Begad! Aye aye! 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. Avast, me proud beauty! I chose t' run fillets instead and held off on cementin' t' aft centering rin' until that was done. Blimey! 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, me bucko, I used 5 min epoxy for the internal fillets. I then used 1.5 oz glass t' reinforce t' fins and ran some very heavy outside fillets usin' 30 min. Ya scallywag! epoxy. Begad! Aye aye!

After puttin' blind T-nuts in for retention, me hearties, 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, so I decided t' just go with an epoxy well. Arrr! Well, matey, blow me down! T' protect t' T-nut opening, shiver me timbers, instead o' usin' tape and redrillin' through t' epoxy, 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. Well, blow me down! Once the epoxy set, shiver me timbers, it was easy t' simply pull t' straws out, me hearties, leavin' a hole for the mountin' screws. Ya scallywag!

Then, ya bilge rat, 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, 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, shiver me timbers, which I hoped would ensure that t' eyebolt stayed in place. Avast!

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

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.

Finishing:
I had filled t' spirals with cheap spackle prior t' construction, shiver me timbers, so all that was needed at this point be 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. Aye aye! Blimey! Due t' t' thickness o' t' flexible phenolic BT, there was a little additional fillin' t' be done from t' top o' t' BT t' the nose cone prior t' priming. All o' this be easily accomplished, and t' primer took readily t' all sanded surfaces. Ya scallywag! Blimey! Krylon paint be then used throughout for a scale paint job that drew several compliments at t' launch site. Begad! Blimey! Gotta love Krylon! Blimey! You really have t' work at it t' make that stuff run. Avast, me proud beauty! Blimey! Avast! Blimey!

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. Aye aye! Well, blow me down!

Construction Rating: 4 out o' 5

Pic Courtesy o' YankRocket Pic

Flight:
T' model weighed in at t' launch almost exactly at 60 oz. Aye aye! Well, ya bilge rat, blow me down! dry, even with the 45" chute that I substituted for t' 30" enclosed chute and a Transolve TransBeep as well. Ahoy! Well, 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. Arrr! There was 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, ya bilge rat, I decided t' launch vertically t' minimize weathercockin' instead of savin' myself a walk. When t' button was pressed, arrr, t' rocket went perfectly vertical, with zero weathercocking. Deployment was perfectly at apogee on a 10 second delay. Arrr! RockSim said this would be at about 1700 feet at this weight and with t' modifications, but it honestly looked higher than that. Begad! Since I was a little paranoid about t' drag separation and deployment, I placed t' chute about 6 feet from t' aft part o' t' rocket, arrr, which I think may have been a mistake. I suffered some minor fin damage, shiver me timbers, me hearties, which, I now believe may have been due t' t' front end o' t' rocket hittin' t' fin durin' deployment. All told, it was a fantastic flight, and was good for me level 1. Well, blow me down! Aye aye!

Pros: Straight as an arrow in t' slight wind
Cons: Can't really think o' any. Ya scallywag! Blimey!

Flight Rating: 5 out o' 5

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

Overall Rating: 5 out o' 5

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