AX-1.0 Patriot

The certification flight flew an AeroTech H100W-14A single-use motor — 227 N·s total impulse, with a 14-second delay grain timing apogee deployment. Recovery is single-deploy: a ~1.2 g black-powder ejection charge pressurizes the airframe and extracts the parachute. Charge sizing was validated through ground ejection testing before flight rather than taken from vendor tables, and the vehicle was recovered undamaged — the L1 requirement.

After certification, the stock cardboard airframe was upgraded for higher-impulse flight: the paint finish was stripped, the tube laminated with epoxy, and a form-fitted PETG-CF armor shell (1/16″ wall) bonded over it — roughly a 3× increase in hoop strength for under 150 g of added mass. The reinforcement targets the 800+ N peak thrust of an AeroTech J425R (609 N·s, ~3,800 ft predicted apogee), with the shell's 250 °C glass-transition temperature adding thermal margin through the high-speed portion of flight.

Every configuration was modeled in OpenRocket before it flew: static stability margin held above one caliber through propellant burn-off, CG/CP tracked across the burn, apogee predicted per motor. ANSYS Mechanical static cases checked fin-can and airframe loads at peak thrust, and Fluent CFD runs examined external airflow and stagnation heating — trivial at L1 speeds, but the same workflow scales to the flights where it isn't.

Stability and total-motion plots from the OpenRocket model: margin versus time through the burn, and altitude, velocity, and acceleration through apogee and recovery. The certification flight tracked the simulated envelope, closing the loop between model and hardware. Click the stack to cycle plots; double-click to enlarge.