Fisher Space Systems LLC

Viper Rocket Trike

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Updated Jun 2024
"Simplicity is the ultimate sophistication."
- Leonardo da Vinci
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Copyright (c) 2021 Jerry F Fisher
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01-30-2024: This month, I worked on the flight system. I moved the servos and control rods to the vertical and horizontal stabilizers and attached them to the frame. The total mass as of this month is ~ 1056 gm. This leaves 446 gm for the paraglider, canopy, and nosecone. Read more in the Jan EOM Report.

02-29-2024: This month, I continued work on the flight system. I finished the paraglider, forward strut, equipment bay, and nosecone. The total mass as of this month is ~ 1190 gm. This leaves 310 gm for the canopy and release mechanism.

03-31-2024: This month, I continued work on the flight system. I finished the canopy and release mechanism. The canopy is made of PLA and has four post that fit into spring loaded sockets mounted on the frame. High resistance wire is used as a fuse releasing the canopy when a high current passes through the wire. The mass of the canopy and release mechanism is ~ 125 gm, less than half of my mass allotment of 310 gm for the canopy and release mechanism. Read more in the Mar EOM Report.

04-30-2024: This month, I continued work on the flight system. I assembled the entire rocket glider. The final mass is ~1.2 kg. This leaves 300 gm for the HTP oxidizer and PLA/KMnO4 fuel. I performed a dry run for launch. Everything checks out. All systems are go for launch next month.

05-31-24: This is the first launch of the MkI Viper. The MkI Viper is powered by a hybrid rocket motor. The oxidizer is ~ 85% hydrogen peroxide (HTP). The fuel is polylactic acid (PLA) infused with potassium permanganate (KmNO4). The total mass of the MkI Viper is ~ 1.4 kg including ~ 150 gm of propellants. As such, the Viper meets the requirements for a class I rocket as defined by 14 CFR 101.22(a). In this video, the propellant load was 50 ml of ~ 80% HTP, 2 ml of Ethanol, and ~ 5 gm of PLA/KMnO4. Total mass of propellant was ~ 78 gm. Flight control is via an RC transmitter and receiver. On this flight, the controls were left in the neutral position to view the take off without guidance. The video shows the Viper yawing to port and pitching down. This can be corrected by rearranging the mass. The objective now is to learn to fly.
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