Kickstart my Heart was my third attempt at a high altitude supersonic rocket. I lost my first attempt, Dancing Queen, after an otherwise nominal flight because the tracking beacon failed at landing, and my second attempt, Heartbeat, after the GPS got blown up by my apogee charge. 

For Kickstart my Heart, I learned from both of these failiures, incorporating both a GPS and tracking beacon. I completely sealed the avionics bay off from the recovery bay with an O-Ring, as well as placed the charge as far as possible from the bulkhead to further shield the avionics bay.  

Another issue I consistently had with these rockets was slop in the coupler. I tried solving this on Heartbeat by using a tapered joint, but the joint still had too much slop with the recovery installed. On Kickstart my Heart, I manufactured a nosecone mold that directly integrated the forward closure/coupler, which meant that the nosecone would fit perfectly onto the coupler.

Kickstart my Heart flew succesfully to Mach 2.5 and 22kft, doubling my personal(recovered) record for both speed and altitude.