PROJECT SUMMARY

Jawbone was a 6” diameter vehicle launched on April 30th, 2022. The vehicle reached an apogee of 41,300 ft AGL, a max speed of Mach 1.717, and a peak acceleration of 7.266 Gs. Jawbone saw multiple new systems in avionics and recovery.

FLIGHT VEHICLE

Jawbone was a low-altitude test vehicle with improvements primarily on the avionics and recovery systems. First, the avionics unit on Jawbone received a number of upgrades. First flown on CTRL+V, USCRPL's custom pancake-style PCB stack conforms around the nosecone deployment CO2 canister, allowing more space in the nosecone. The system featured a new custom battery charging and management PCB to prolong pad standby time. Additionally, this was our first flight of the Lightspeed Rangefinder, an in-house designed and built tracking unit that used four ground stations positioned around the launch site to triangulate the position of Jawbone following its flight.

We lost communications with the main avionics unit a few seconds into flight due to a ground side antenna issue. Lightspeed Rangefinder ground stations continued to track the rocket and collect positional data, which proved valuable during the recovery effort of the vehicle. The avionics unit itself performed nominally, collecting GPS, inertial, and barometric data which we analyzed after recovery to determine the vehicles performance.

The Jawbone recovery system featured a next-generation design with improvements from the CTRL+V dual deployment recovery system. Using a connector and extension wire running along the forward shock cord segment, USCRPL's custom avionics unit attempted to control the active deployment of the main parachute when the vehicle reached a decent altitude of approximately 5,000ft. Unfortunately, the recovery system experienced a partial failure resulting in the main parachute failing to open. The drogue parachute still successfully deployed, so the vehicle was recovered intact. The main parachute, which was constrained using a Tender Descender, never deployed due to unexpected loads during nosecone deployment disconnecting the cable attached to the Tender Descender. Additionally, main deployment was never commanded by the avionics unit due to differences between the simulated and actual performance of the vehicle causing touchdown to occur sooner than expected.