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, coupler, 8 nicely cut 1/4" plywood fins, 3 1/4" plywood centerin' rings, bulkhead plate, U-bolts, matey, me bucko, matey, 10' tubular nylon, parachute, launch lug, and nose cone. Aye aye! All around high quality material. However, me hearties, thar was no provision t' attach t' nose cone to t' payload bay. Avast! You have t' supply your own hardware for that. Arrr! You also have t' supply motor retention hardware. Aye aye! On t' other hand, matey, me bucko, t' U-bolts came securely attached t' t' appropriate rings.

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

T' rings fit a bit loosely, ya bilge rat, so you have t' be careful t' keep them level. Avast, me proud beauty! I beveled t' leadin' and trailin' fin edges 22.5 degrees usin' a router table and a panel-raisin' bit. Aye aye! 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, me bucko, and aligned by clampin' wooden stakes betwixt t' main and secondary fins. Blimey! T' fin tabs were 1/16 t' 3/32" too long, and so t' fin roots were "elevated" off t' body tube, requirin' a fillet under them.

I added a PML modular baffle at t' top o' t' motor mount, me bucko, me bucko, and T-nuts for motor retention at t' aft centerin' ring. Avast, me proud beauty! I also added T-nuts t' retain rail buttons. Well, blow me down! I did this by nay securin' t' aft centerin' rin' until after the motor tube was glued in. Aye aye! 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! Blimey! It took four pumps o' West epoxy (+ thickener) t' finish those. Well, blow me down! Blimey!

I got some removable white plastic rivets from Rocketmotion t' secure the nose cone.

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

Finishing:
I didn't finish it. Begad! 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, I357-6, shiver me timbers, I161-6, ya bilge rat, I156-6. Begad! Aye aye! I ended up usin' a Pro38 3-grain motor (384I205) with a 9-second delay. Well, ya bilge rat, blow me down!

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

There be a light wind.

Immediately after leavin' t' rail, matey, t' rocket went into skywriter mode, did about 4 full loops, me bucko, and landsharked under full power. Blimey! Ejection occurred after t' landshark.

Recovery:
On impact, me hearties, one fin ripped off. Ya scallywag! T' payload bay had a slight crinkle. T' damage should be easily repairable, me hearties, 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. I'll also be able t' get more room for t' chute by shortenin' t' coupler.

DEFINITELY ADD NOSE WEIGHT. Begad! Ya scallywag! This rocket is unstable if built accordin' to the manufacturer's instructions. Avast! If anything, arrr, me CG was forward o' standard, ya bilge rat, 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. Ya scallywag! Pretty rocket. Lots o' people were wondering where I got it. If only t' vendor would talk about nose weight in the instructions, matey, t' flight ratin' would have been higher (e.g., about a 4, I bet).

Overall Rating: 3 out o' 5

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