Shane's Tripoli Level 3 Certification
This is my Level III Tripoli High Power Rocketry Certification Flight. The flight was flown October 27th, 2013. The rocket flew to 7,500 Feet in about 18 seconds. Top speed was 530 Miles per hour at burn out, which was about 2.7 seconds after lift-off from Red Dry Lake, approximately 23 miles North of Kingman, Arizona. I'd like to thank my TAPS: Pat Gordzelik for design review and approval, and Jack Garabaldi for design review and primary launch witness. It was a pleasure working with you both! I'd like to thank former girlfriend Connie Bousselaire for her photography and videography documenting my effort and the performance of the rocket. Her enthusiastic support and companionship were invaluable. I'd also like to thank long-time friends and ground crew support Ken Sparks and Guy Smith, without whose efforts and fellowship would have made this a much more difficult launch day. Thank you to Ken for the loan of his launch tower. Thanks to Nate for the use of his remote ignition system! Thanks to MARS for the great launch location and event! The Motor was a Cesaroni Technologies Incorporated (CTI) M1350 with triply redundant electronic deployment. The deployment electronics consisted of the Primary controller- a Featherweight Raven III altimeter, the Secondary controller- a Altus Metrum TeleMetrum V 2.0, and the Tertiary controller- a Marsa Systems MARSA 54. The deployment charges numbered six (6) total charges. Three charges in the drogue parachute bay and three charges in the main parachute bay. Each charge is progressively greater- the blow it out or blow it up philosophy. The charges were calculated using the calculated volume of free air in each bay. I created a spreadsheet to determine the free air volume of the drogue bay and the main parachute bay in order to determine the PSI required to shear the nylon screws that functioned as the shear pins. Just enough force to overcome the shear strength of the pins, but not so much as to create shock loads when the tethers were fully extended. This extends the lifetime of the parachute harnesses and anchor points. I don't believe in overly aggressive deployment that seems so popular these days. Get the masses moving and let gravity and flight aerodynamic forces do the rest of the work. Power is supplied by Lithium Polymer (LiPo) batteries and is switched using Featherweight's Magnetic switches. I like these switches because they are lightweight and there's no ungly switch or wires hanging out into the air stream. Also, any G-loading of mechanical switches is avoided with this approach. Power is also a redundant feature of this rocket- each flight controller has dedicated battery and magnetic switch. Total design and build time was approximately 9 months of nights after work and weekends. I used RockSim to design and verify rocket performance. I precisely measured weights and dimensions and included them precisely where in the airframe they were located. Build weight precisely matched design weight. I modeled launch field conditions from almanac data and updated simulation with forecast data two days in advance of launch. Launch day conditions were as simulated and resulted in nearly exact match performance. Please feel free to ask any questions. Shane

 Rocketry Product: Featherweight Altimeters - Raven {Component}

 Rocketry Product: Marsa Systems - Marsa33LHD {Component}

Author Shane Justice
Duration 216 seconds

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