The Payload Recovery bay sits just below our rocket's payload. When the rocket is descending under parachute, it fires a black powder charge to push the payload out of the airframe. The main and backup charges are triggered by dissimilarly redundant altimeters to ensure that they fire at the correct time even if a charge or altimeter fails.

I designed a 3D printed polycarbonate part to hold the batteries, arming switches, and altimeters, as well as the fiberglass bulkhead that took the force of the firing charges.

I went through several iterations of 3D printed PLA prototypes with laser cut wooden bulkheads. This allowed me to fine tune the tolerances in the printed parts and gave me useful experience with changing my design to make assembly easier.

After the final version was assembled, we tested the system with the full payload. 

The amount of black powder was miscalculated and ejection forces were much higher than what had been designed for, but the system survived with no damage due to its high factor of safety.

That summer, I went to The Spaceport America Cup to set up and integrate the recovery bay.

During the flight, the system worked exactly as expected and ejected the payload at the correct altitude. 

of 158 teams at the event, our team won 3rd Place in the payload award!