Meanwhile, in my "clean room", I am laying out the main avionics bay. The Jayhawk will recover with an intact airframe, using a Defy Gravity "Tether" to release the main parachutes. Similar to many dual deploy rockets, the avionics bay is inside the coupler between the motor section and the payload section of the airframe. The coupler does not, however, separate in the apogee event. It functions as a body joint, allowing the rocket to come apart for transport, but is permanently attached to the lower body. The reinforced forward plate of the avionics bay is the attachment point for the recovery harness, and carries the stress through all-threads to the motor mount and main wing. The forward body tube is non-load bearing in the recovery.
I will be flying two sleds, with 4 Perfectflite MAWD altimeters. All four have flown previously in various paired combinations to verify their operation and accuracy. In addition, a separate avionics bay will be in the nose cone, and will contain a GPS tracker and transmitter for real-time downlink of altitude and position information, and a separate radio locator beacon.
If everything operates correctly...
At apogee, independent altimeters in the avionics bay fire redundant black powder charges in the forward payload bay, overpressurizing the forward payload bay, which pushes the nose off and deploys the drogue parachute. The drogue parachute pulls out a 40 length of shock cord attached to the top of the main parachute deployment bag, which is held in the forward payload bay by the tether.
The rocket falls under the drogue parachute until approximately 1100 AGL, at which point the primary altimeter fires a 1/4 gram black powder charge within the Tethers combustion chamber. (The secondary altimeter fire a different 1/4 gram black powder charge at 900 AGL as a backup.) This overpressurizes the interior cup of the Tether, forcing the two halves apart, which releases two quick links. The bottom link remains attached to the forward avionics bulkhead, and also retains both halves of the tether combustion chamber cup via a stainless steel cable. The forward link, now free to leave, allows the drogue parachute to pull the main parachute deployment bag out of the forward payload bay. The drogue pulls the deployment bag off of the main parachutes and then separates with the nose cone. The main parachutes inflate and bring the remainder of the rocket gently to earth.