Scratch - Little Brute {Scratch}

Scratch Little Brute Original Design / Scratch Built

Scratch - Little Brute {Scratch}

Contributed by Matt Gillard

Manufacturer:

Brief:
This is me first attempt o' a scale change. T' Big Brute is a rocket that I built a few years back but have never flown. Begad! Arrr! With t' 2008 challenge callin' for a scale change on a rocket, I thought I’d might as well get somethin' from t' original Big Brute. Avast! Avast! Lookin' through me collection o' nose cones, t' only one with t' same profile as t' Big Brute be a 13mm diameter nose cone, arrr, t' rest o' t' scalin' followed givin' a minimum diameter tumble recovery small brute.

Construction:
Parts need

2.2" BT-5 body tube
Launch lug
1/16" balsa sheet
Nose cone from a defunct Estes fireflash - (P/N 072600, PNC-5A)
Clay mass

Also used was

Bostik glue
Pink spray paint
Pink paper
Black tape
A photocopier

T' scale from t' nose cone be t' be a 7.5 downscale which is about 13-14% o' t' original. Ya scallywag! This makes t' body tube t' be 2.2 inches long. Aye aye! T' fins were down scaled from t' original usin' a photocopier t' make a template. See EMRR featured tips on how t' do this.

scratch_littlebrute_onthepad Apart from that t' rocket builds itself. Blimey! My major concern that unlike all t' min diameter 13mm rockets that I have flown in t' past, this rocket does nay has much in t' way o' aft fins that lower t' CP t' somewhere safe. Well, blow me down! T' 13mm motor really does lower t' CG, shiver me timbers, so I added 3g o' clay t' t' nose cone. Well, blow me down! I used Spacecad t' check things out and it came back okay.

T' whole rocket be painted pink t' match me original Big Brute, felt tip marker was used t' black out t' fins. Begad! Blimey! Three strips o' black tape were added t' give t' strips. T' name o' t' rocket, matey, Little Brute was printed on pink paper and then glued into place. Begad! Arrr! I could nay brin' myself t' put t' original name in such a small rocket.

Flight:
First flight was on a 1/2A3-4T motor. Take off was very fast. Blimey! Well, shiver me timbers, blow me down! At about 100 feet it took a right angle turn and shot off sideways. On recovery, me hearties, t' little brute was nose cone buried and had stripped its launch lug. Begad! Spacecad predicted 472 feet, this flight be nowhere near that.

After gluin' a new longer lug, matey, ya bilge rat, two more flights were made a few days later on 1/4A3-3T motors. Ya scallywag! Each time t' flight was arrow straight with no deviation from t' flight path seen. Begad! Avast, me proud beauty! On each recovery t' little brute buried itself in t' soft earth. Avast! spacecad version 3 does nay have t' 1/4AT motor profile. Ahoy! I imagine that version 4 does.

Summary:
Pro: It's small and I can get motors for it, matey, ya bilge rat, unlike t' big brute where I have t' get an explosive license and have t' police visit me house every year t' see a wooden box.

Con: Ballistic recovery - never good.

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