Project
913 Flights

Results

• Not such a good day. All four rockets failed in one way or another. The main cause of all the failures was the end cap blowing out the top of the rocket.

Construction

• The end caps were constructed of 1/2" of RTV silicone and a inverted 1 1/4" PVC cap bolted to the engine case by four 1/4-20 x 1/2 steel bolts. In the past, a gasket ring of silicone was used in conjunction with Pourstone for the end cap. This arrangement worked well and I thought that if a gasket ring of silicone worked well, a layer would work even better. The RTV Silicone was to provide a flexable seal while the inverted 1 1/4 PVC cap was to provide the structural support needed to contain the combustion gasses. It may be that the RTV Silicone was too flexable and allowed the hot gasses to spread under the seal and weaken the PVC.
• The fins were quick and dirty, designed to allow just enough stability to test the engine without too much labor involved in their construction. 1/4 x 2 1/2 x 8 strips of pine were attached to the rocket fin canister with 8-32 x 2 steel machine screws.
• A smoke tracer and ejection charge was built into the nosecone. The smoke charge was made from West Systems Epoxy and Kno3. This arrangement did not work very well.

Pros

• None.

Cons

• End caps need work.
• Smoke and ejection design needs work.

Pictures

• Engine casings bent from the hot fuel. A metal casing was used in future engines to eliminate this problem.
• Nosecone with tracer smoke hole.
• Fin section.
• Another view of the fin section.
• Painted fin section with rail guide.
• End caps with RTV Silicone.
• Ejection charges being installed in nosecones.
• View of ejection charges.
• New igniters.
• Finished nosecones.
• Finished engines and forward sections.
• Finished rockets.
• Me next to the rockets in the desert.
• Flight 02.
• Flight 03.
• Flight 04.

Video

• Flight 01.
• Flight 02.
• Flight 03.
• Flight 04.

CAD Drawings

• 913 rocket design.

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