Gas Gas Gas - Mach 3 Experimental Rocket

grabcad

CAD file of Gas Gas Gas. This rocket was launched at FAR on December 2, 2023. The expected altitude was 18.8kft, and +Mach 3 at less than 1500ft AGL. The motor is a 5-grain PropX and 2-grain Blue Thunder in a 5G RCS single-use EMK (K1760 ~ 1.4s burn).JLCPCB manufactured the nosecone tip, and the fincan and coupler were printed by 3dpnxt on Craftcloud in aluminum.The nosecone was molded using fiberglass sleeves.The flight computer is a Easymini, with an RDF beacon for tracking. Based on the RDF beacon, the flight was ballistic: it stopped transmitting at the expected ballistic impact time. However, the up part was perfect. The cause of failure is unknown as the rocket was never found. One possible cause is the locking of the nosecone to the coupler due to the shallow angle. A possible improvement is to reduce the contact area by adding a recess on the coupler. More pictures can be found here: https://www.rocketryforum.com/threads/gas-gas-gas-a-single-use-5g-emk-rocket.183548/Feel free to improve on the design.Launch picture by Julian Rice.EDIT:The rocket was found in June 2024, 1.3 miles from the launch pad, lying on the ground. Observations after taking apart the crushed avionic and recovery bay:-Main charge didn't fire but lost continuity.-Reefing ematch fired.Luckily, the Easymini flash chip survived the crash:-Maximum barometric altitude AGL: 6362m-Maximum barometric velocity: ~965 m/s (about Mach ~2.8)-Apogee at T+24.6s-Impact at T+69.2s @ ~180m/s-The main charge showed continuity until it was "fired" at apogee, then lost continuity without igniting. CC BY-NC-SA: This license allows reusers to distribute, remix, adapt, and build upon the material in any medium or format for noncommercial purposes only, and only so long as attribution is given to the creator. If you remix, adapt, or build upon the material, you must license the modified material under identical terms.