The BerthaVostok

Designed and built by Steve Kristal
(Lets just say greater than 25 years o' buildin' rockets.)

Design :

T' design concept for t' BerthaVostok originated with an invitation t' my local NARRRRR branch's Bertha Bash night, ya bilge rat, where t' goal be t' kit-bash something original from a standard Estes Big Bertha kit. Arrr! Arrr!

Havin' seen Gordon Agnello's Gemini Bertha and his brother's Redstone Bertha, matey, me hearties, shiver me timbers, I decided t' take retro-Bertha even a little further back with a Vostok version. Avast, me proud beauty! Blimey! Ya scallywag! Blimey!

T' design began with a standard Estes Big Bertha, ya bilge rat, and all t' original kit parts were used except t' shock cord which I replaced with Keelhaul®©™ and a shorter launch lug.

T' Vostok part o' t' build be modeled after Peter Always's "Simplified Vostok". Begad! Aye aye! Blimey! (see http://yellowjacketsystems.com/alway/plans.htm#Vostok ). Well, blow me down! Arrr! Blimey!

I upscaled t' design t' a BT-60 and instead o' usin' Peter's actual templates, ya bilge rat, matey, I made me own usin' t' graphics from a free paper model by Lars Folman downloaded from t' web (see: http://hjem.get2net.dk/). Avast!

T' body tube graphics were resized from t' paper model as well and printed onto full-size label paper which I used as a body wrap. Avast, me proud beauty! Blimey!

T' hardest part was sizin' and makin' t' transition sections. Begad! Their length was based on t' space "left over" betwixt t' lower portion o' the upper body wrap and t' upper cone o' t' strap-ons. Avast, me proud beauty! I significantly compressed the graphics on t' upper body wrap t' leave enough room for t' transition. T' overall effect is definitely Vostok-like, me bucko, me hearties, but both t' upper graphics and the transition are way shorter than either scale or Peter Always's version. Begad! Ya scallywag!

As for stability planning, me hearties, me hearties, thar was no way I could RockSim this. Ya scallywag! Well, blow me down! Instead I simply assumed that addin' those big honkin' Bertha fins t' an already stable Peter Alway design wouldn't cause any problems. Avast! I was right.

As for power, ya bilge rat, additional weight be negligable with t' four strap-ons and transition made from paper. Arrr! My only concern was all t' added drag, but I figured t' basic Bertha has plenty o' power on a C6. Ahoy!

Construction:

Construction began with t' standard Bertha build up t' t' point of attachin' t' fins. Avast! Upper body wrap was then applied. Avast! Next, shiver me timbers, t' upper transition section, matey, with a paper centerin' ring, was slid up over t' bottom of the tube t' meet t' upper body wrap. T' lower body wrap was then applied, and the lower transition section slid up over that t' mate with t' upper section. Avast!

While I anticipated later puttin' on fins, and left cutouts on t' lower body wrap for their placement, ya bilge rat, arrr, I should have also added placement lines for the strap-ons, me hearties, which I built and placed next. Arrr! Begad! Blimey! T' strap-ons were made from 100# card stock with t' graphics printed directly on. Ahoy! Their bottoms were "plugged" with card stock circles with appropriate graphics. Avast, me proud beauty! Well, blow me down! Blimey!

T' fins were covered with label paper graphics. Avast! Blimey! T' fin edges were left flat, shiver me timbers, and then blackened with permanent marker. Avast, me proud beauty! T' fins were then placed in t' cutouts left on t' lower body tube graphic, and filleted with white glue. Ahoy!

Because o' t' width o' t' transition, t' launch lug was applied t' a cut out on one o' t' fins. Blimey!

T' only paintin' was t' nosecone, shiver me timbers, which be Soviet-era olive drab. Blimey!

Overall, t' build be fun, but if I did it again I would place t' fins first, and then t' strap-ons. Blimey! Aye aye! Both would be a lot straighter if I had done it that way. Blimey! Blimey! But, shiver me timbers, me bucko, me bucko, on t' other hand, t' flights wouldn't be nearly as interesting.

Flight & Recovery:

Flight o' this rocket is surprisingly straight, me bucko, considerin' t' lack of positionin' aids for both t' fins and strap-ons. Avast, me proud beauty! It flies kind o' like a cross between a Bertha and a saucer as it tail wags it's way up. Avast! Aye aye! Really fun t' watch and recovers easily on t' standard Bertha chute.

Hits about 400' on a C6 but did an end-over-end flip on a B6 (possibly a bad engine, matey, and really cool t' watch, shiver me timbers, but I won't try that again). Aye aye!

Conclusion:

Overall, arrr, ya bilge rat, one o' t' stupidest rockets ever built. A marriage o' t' genius of Sergei Korolev and Vern Estes. Really, really fun t' build and fly, and lots of laughs from those who know and love rockets. Avast! Begad!