Blog
Fisher Space Systems LLC
Viper Rocket Trike
Updated Feb 2026
"Simplicity is the ultimate sophistication."
- Leonardo da Vinci
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Copyright (c) 2021 Jerry F Fisher
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Copyright (c) 2021 Jerry F Fisher
01-31-2026: This month, I worked on increasing the flow rate and thrust of the class II rocket motor. I increased the HTP ignition flow rate to ~ 71 ml/sec using three stainless steel 1/4" spray nozzles. Using the single port PLA fuel core design as a basis, I designed a new three port PLA fuel core segment. With this fuel core, I should get ~ 75N (~ 17lb) of thrust. During combustion, I plan to throttle up to ~ 100N (~ 22lb).
02-28-2026: This month, I worked on the class II fuel core. I printed out two 3 port 6 cm long fuel core segments and infused them with KMnO4. To prevent the fuel core segments from separating during burn, I screwed them together with a nylon screw. The next step is to assemble a rocket motor to test the fuel core segments. The objective is to determine the extent of infusion into the larger diameter PLA fuel core and to determine if the fuel core segments will stay together during burn. Also this month, I continued experimenting with a stainless steel motorized ball valve.
02-28-2026: This month, I worked on the class II fuel core. I printed out two 3 port 6 cm long fuel core segments and infused them with KMnO4. To prevent the fuel core segments from separating during burn, I screwed them together with a nylon screw. The next step is to assemble a rocket motor to test the fuel core segments. The objective is to determine the extent of infusion into the larger diameter PLA fuel core and to determine if the fuel core segments will stay together during burn. Also this month, I continued experimenting with a stainless steel motorized ball valve.
