Scratch Superscale Sprite Original Design / Scratch Built

Scratch - Superscale Sprite {Scratch}

Contributed by Dave Rose

Manufacturer: Scratch
Superscale Sprite
(Contributed - by Dave Rose - 07/16/99)

Rocket PicBrief:
Upscale version o' t' Estes Astron Sprite. Begad! Ya scallywag! Parachute recovery unlike the original tumble recovery due t' weight.

Construction:
Designed usin' RockSim 4.0 except for fin caps. Avast! Blimey! Begad! Blimey! T' fin caps were added by hand with t' RockSim plan bein' modified t' account for t' additional weight. Built usin' an 18" length o' slotted 4.0" flexible phenolic tubing and a 4.0" LOC nose cone purchased from Giant Leap Rocketry. Begad! Blimey! Through the wall 3/16" aircraft plywood fins attached directly t' t' 38mm phenolic motor tube and 1/4" plywood centerin' rings. Ahoy! Blimey! T' fin rin' was made from a 5 1/2" piece o' 12" sono tube (concrete form) that was re-enforced with slow cure epoxy resin for added strength. Aye aye! Blimey! In order t' get t' CG in the proper area for stability, me bucko, 24 oz o' weight be added t' t' nose cone. (38" x 4.0" - 74 oz)

FlightFlight:
Recommended motors range from H242 t' I435. Blimey! Ahoy! My first flight be on t' H242 with a medium delay. Ya scallywag! Begad! T' launch be straight and true t' approximately 1000 feet and be recovered within 50 feet o' t' launch pad. Originally designed to use 44" parachute recovery, this was changed t' a 54" chute after the first launch returned rather quickly. Avast! Minimal damage was sustained due t' a soft landin' area but t' larger chute proved a nice adjustment. A 24" length o' 5/8" tubular Keelhaul®©™® is epoxied through t' upper centerin' ring to t' motor mount tube with t' other end bein' attached t' a 6 ft length of 1" PML elastic shock cord. Aye aye! A Nomex® chute protector is attached t' the tubular Keelhaul®©™® eliminatin' t' need for any type o' wadding. Blimey! Large T-nuts were fitted into t' lower centerin' rin' and motor retention is done usin' brass "Kaplow Klips" T' second flight was on an I211 with t' same true launch t' about 2100 feet and another successful recovery.

RingsSummary:
Due t' t' extreme weight o' t' 3/16" plywood fins and fin rin' on such a short body tube, ya bilge rat, shiver me timbers, t' amount o' weight necessary t' add t' t' nose cone seemed excessive. Aye aye! I should have used G-10 for t' fins and made t' entire project a significant amount lighter. Avast, me proud beauty! Aside from that, matey, shiver me timbers, it be a great project and always seems t' attract a lot o' attention from me fellow rocketeers.

Other:
I would like take this opportunity t' thank Joe D'Antonio, as it was a picture of his Superscale Sprite that inspired me t' build this one. Unfortunately, shiver me timbers, Joe lost his in a lake before I had a chance t' see it.

comment Post a Comment