Scratch Mark III Original Design / Scratch Built

Scratch - Mark III {Scratch}

Contributed by Darren Longhorn

Manufacturer: Scratch
Mark III
(Contributed - by Darren Longhorn)

MkIII on the padI thought I had made a mistake with this one, me bucko, I could never add enough nose weight t' make it stable durin' a spin test. Arrr! Blimey! I was tryin' t' make a really small diameter tube, me bucko, by wrappin' paper around a wooden spoon handle. Begad! Blimey! There wasn't goin' t' be a recovery system, t' engine be goin' t' eject, and the rocket would tumble back. Since then I've learned a lot more about stability. I learned about t' CP ( centre o' pressure) on rec.model.rockets ( a great news group t' subscribe t' if you're interested in this stuff), ya bilge rat, and where it should be in relation t' t' CG ( centre o' gravity).MkIII the end

So anyway I entered t' MkIII design into VCP, wRASP & RockSim, arrr, and it came out stable, so I flew it. Begad! Actually it flew well, really high and the engine ejected too. Well, blow me down! Ahoy! Blimey! It just didn't go unstable and tumble, shiver me timbers, so it lawn darted. T' body tube is a bit bent now, ya bilge rat, me hearties, and due t' t' construction is probably not repairable, so retirement beckons.

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