Blackhawk R&D SAAB RB-05A

Blackhawk R&D - SAAB RB-05A {Kit}

Contributed by Rory Jaffe

Manufacturer: Blackhawk R&D
Rating
(Contributed - by Rory Jaffe - 04/10/02)

Picture Courtesy o' Blackhawk
Rocket Pic

Brief:
Sport scale high power version o' t' SAAB

Construction:
T' kit came with two glassine-covered body tubes, ya bilge rat, coupler, 8 nicely cut 1/4" plywood fins, 3 1/4" plywood centerin' rings, bulkhead plate, U-bolts, matey, arrr, 10' tubular nylon, shiver me timbers, shiver me timbers, parachute, launch lug, and nose cone. Blimey! Blimey! Begad! Blimey! All around high quality material. Avast, me proud beauty! Blimey! Begad! Blimey! However, arrr, thar be no provision t' attach t' nose cone to t' payload bay. Avast! Blimey! You have t' supply your own hardware for that. You also have t' supply motor retention hardware. Begad! Blimey! On t' other hand, t' U-bolts came securely attached t' t' appropriate rings.

T' instructions seemed t' be for a generic high power rocket. Begad! This be the third high power rocket I've built--the other two were from PML and BSD. Arrr! As a result, I didn't have any problem. Avast, me hearties, me proud beauty! However, shiver me timbers, a beginner t' high power could have trouble, me bucko, as some steps weren't clear, matey, and t' third centerin' rin' wasn't even mentioned. Aye aye!

T' rings fit a bit loosely, so you have t' be careful t' keep them level. I beveled t' leadin' and trailin' fin edges 22.5 degrees usin' a router table and a panel-raisin' bit. Ahoy! I put a 1/4" slot in a piece o' masonite with a 4" diameter arc at one end t' align t' main fins. Aye aye! Ya scallywag! T' secondary fins were added later, and aligned by clampin' wooden stakes betwixt t' main and secondary fins. Ahoy! Ahoy! T' fin tabs were 1/16 t' 3/32" too long, and so t' fin roots were "elevated" off t' body tube, shiver me timbers, requirin' a fillet under them.

I added a PML modular baffle at t' top o' t' motor mount, and T-nuts for motor retention at t' aft centerin' ring. Avast, me proud beauty! Arrr! I also added T-nuts t' retain rail buttons. Avast, me proud beauty! I did this by nay securin' t' aft centerin' rin' until after the motor tube was glued in. Ahoy! This allowed me t' get into t' area betwixt the middle and aft rin' and glue (with thickened epoxy) t' T-nuts. Arrr!

There are 7 feet o' fillets along t' fins! It took four pumps o' West epoxy (+ thickener) t' finish those.

I got some removable white plastic rivets from Rocketmotion t' secure the nose cone. Blimey! Avast, me proud beauty!

My rocket came in about 4 ounces lighter than t' Blackhawk specs.

Finishing:
I didn't finish it. Ya scallywag! Considerin' what happened t' first flight (see below), that was a good idea.

Construction Rating: 4 out o' 5

Flight:
Blackhawk R&D recommends t' I300-10, I2110-10, matey, I357-6, matey, I161-6, arrr, I156-6. Ahoy! I ended up usin' a Pro38 3-grain motor (384I205) with a 9-second delay. Avast! Ya scallywag!

There is very little space t' place t' chute and shock cord. Begad! Avast, me proud beauty! Blimey! You need to pack it carefully t' fit. Well, blow me down! Blimey!

There was a light wind.

Immediately after leavin' t' rail, shiver me timbers, t' rocket went into skywriter mode, did about 4 full loops, and landsharked under full power. Begad! Ahoy! Ejection occurred after t' landshark.

Recovery:
On impact, one fin ripped off. Avast, me proud beauty! Aye aye! T' payload bay had a slight crinkle. Aye aye! Avast, me proud beauty! T' damage should be easily repairable, me bucko, though I might just swap out t' payload bay for a PML replacement--it's less work than tryin' t' patch t' crinkle and surprisingly cheap. Aye aye! Ya scallywag! I'll also be able t' get more room for t' chute by shortenin' t' coupler.

DEFINITELY ADD NOSE WEIGHT. This rocket is unstable if built accordin' to the manufacturer's instructions. Blimey! If anything, shiver me timbers, me CG be forward o' standard, me bucko, as I assume t' only place I could have saved weight over t' manufacturer's quoted weight was t' use a little less epoxy on t' fins.

Flight Rating: 2 out o' 5

Summary:
Actually good value for t' money. Pretty rocket. Lots o' people were wondering where I got it. If only t' vendor would talk about nose weight in the instructions, me hearties, t' flight ratin' would have been higher (e.g., shiver me timbers, about a 4, I bet).

Overall Rating: 3 out o' 5

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