The booster is now complete for the flight test of the Mk2 stager. The sustainer needs a little more tape, and a coat of paint on the fins and it too is ready to go.
The booster is only a 2.1L spliced pair, and the sustainer is only 600mL. We built both of them small so we could test the stager at the local park. For this test we weren't all too concerned with aerodynamic efficiency. The booster uses the same parachute deployment technique that the drop away boosters use on the Polaron rocket. The parachute is behind a flap held by a wire. The other end of the wire is attached to the sustainer and as soon as the sustainer is released, it pulls the wire and deploys the parachute on the booster.
The sustainer does not have a recovery system. It just has a soft nosecone to protect it (somewhat) on landing.
We don't expect this combination to go very high, and we still need to run simulations to see what to expect. If the weather is good this weekend we will launch it.