In January of 2017, I joined a team building a 2 stage solid rocket with a target altitude of 30,000 ft.

I ran booster development. My primary design responsibility was the interstage for the vehicle, which was responsible for keeping the upper stage stable during ascent, separating the upper stage from the lower stage, and holding the upper stage igniter in place until ignition. The photo is from a boosted dart flight in Tennessee, where the upper stage motor was replaced with inert mass to ensure successful separation of the stages. This test flight was successful.

Unfortunately, the upper stage was not recovered on the final flight of the vehicle in Kansas.