Scratch - Crew Exploration Saucer {Scratch}

Contributed by Dick Stafford

Manufacturer: Scratch
(Contributed - by Dick Stafford - 04/17/06) (MODS) Crew Exploration Saucer

Brief:
I really like my Art Applewhite 6" Delta saucer. However, since it appears that it will last for many, many more flights, I didn't think I needed a second one just yet. So what to do with my Spaceship Earth Delta?

Modifications:
I began by constructing the Delta: Cut and form the top and bottom shrouds and the center foamboard plate, bevel the edge of the plate, and glue the top shroud to the plate. Then in place of the provided motor tube, I merely used an 12" Apogee 24mm tube. Finally, I added the bottom shroud, making sure the launch rod guides on all components were aligned.

Construction:
The build requires:

  • 1 Spaceship Earth Delta Saucer (6" diameter with 24mm MMT)
    • 1 sheet of cardstock - top and bottom shrouds
    • 1 ~ 7" square piece of foam board - center plate
    • 1 24" motor mount (not used)
  • 1 12" long Apogee 24mm body tube
  • 1 balsa nose cone
  • 1 Eye hook
  • 1 Kevlar® twine
  • 1 Small piece of a spent 24mm motor casing
  • 12" plastic parachute
(MODS) Crew Exploration Saucer

The rest was trivial: hook eye in the cone and attach the shock cord to the body. For the latter, I used a small piece of a 24mm motor casing. I notched the outside so that when the Kevlar® was tied around, it would lie flat with the outer rim. This was mounted several inches down into the body tube.

I simulated the saucer in RockSim8 using Bruce Levison's 'short stubby' simulation techniques as presented in Apogee newsletters #154 and #158.

The Spaceship Earth saucer's name comes from the fact that it has a projection of the Earth printed on it. The 24mm cone I had laying around resembled a capsule (any cone would work). NASA's Crew Exploration Vehicle is in the news. Hmmm, guess I'll call it the Crew Exploration Saucer.

Finishing:
Finishing consisted of painting the cone white and creating some wraps on my inkjet printer. The lower wrap has nozzles, flames, and smoke. The top is the Pantone color specified for models of NASA's CEV and a NASA logo.

(MODS) Crew Exploration Saucer

Flight:
Simulations said it would be stable under any conditions. I loaded dog barf wadding and a 12" Estes chute, friction-fitted a D12-3, and tested out the theory.

Recovery:
It flew just fine although the ejection, even with the short delay motor, was a bit late. Nevertheless, the chute opened and it recovered well.

Summary:
This was just another use for Art's simple yet robust kits. If you have an extra, you might try making a variation on this theme. This rocket needs long burn, short delay motors!

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