Clubs / Tripoli Central California (TCC)
Madcow Level2 Rocket Launch, AeroTech J800T

A full 1280 N-s J800T Blue Thunder motor in an 11.5 lb fiberglass rocket. I love the separated Violet/Blue Flame some feet behind the rocket. Launch Event: TCC August 20th 2016 Launch Location: Maddox Diary Farm, Helm CA Rocket: Madcow/Apogee "Level-2" Motor: Aerotech RMS 54/1280 J800T (smoke grain only, charge defeated) Altitude Reached: 4759 ft Maximum Velocity: 634 ft/sec The 14 second delay grain was expected to be too short. Thus the delay grain was greased on top, and wadding was installed in the charge cup rather than black powder. The StratoLoggerCF main altimeter worked flawlessly, as did the Eggfinder Quantum Backup Altimeter. Drogue deployed at Apogee and main at 700 ft AGL. This was my first J800T.   The motor performed excellent, though there are a couple of minor anomalies that I noticed... When I went to build it, I noticed that the instructions showed that it used a Medusa Nozzle, but my J800T-L RMS kit had a single large nozzle.   I then looked up the AeroTech assembly drawing for the J800T and it also showed the Medusa Nozzle.    I was concerned that I didn't have the correct nozzle in my RMS kit. Finally, after some google searches, I found some comments on TRF that this load started shipping with a single large nozzle.   All went well with the flight on the larger nozzle. I'm not certain how the thrust curve would be affected, but juding from the motor burn in my video, it burned 0.3 seconds longer than the thrust curves published for the J800T.   The spec sheet says 1.6 seconds burn, but I measured 1.9 seconds.   Thus the average thrust was lower than 800 N.    The total impulse was still around 1280 N-sec.    1280/1.6 = 800N, but from my flight, 1280/1.9 = 675N Average Thrust.   I think this motor might push my bird over 5K on a day with no winds.   For my rocket, I think it's the best performing 54/1280 RMS reload. I noticed a copy and past error... the second title line should say 'August" Launch Event... not July.

Author 2101Striper
Duration 218 seconds

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