What began as a professional consultation soon became a long-term friendship. Working together, often from Piovoso’s home office, the pair developed a novel approach for controlling pressure and thrust in solid rocket motors. Their method was later patented and became part of a NASA program supporting Orion’s launch abort system. 

At the core of that system is a rocket motor designed to rapidly move the crew capsule away from the launch vehicle if needed. It does this by controlling how high-pressure gases from burning propellant are released through multiple nozzles.

“A rocket works by creating gas in a burn chamber at high pressure, then releasing that gas through nozzles to create force,” Piovoso said. “When you receive a command for a direction, you calculate the pressure needed to generate that force, then adjust the chamber pressure quickly and hold it while the force is being applied.”

In practice, that control comes down to regulating how much gas flows through the nozzles. If the opening is too large, pressure drops because gas escapes too easily. If it is too small, pressure builds because the gas cannot exit fast enough. In Orion’s system, eight nozzles can be adjusted to control both the total thrust and its direction.

The engineers had to balance competing demands. They needed the system to respond rapidly to changing conditions while minimizing fuel use to maximize how far the capsule could be steered to safety. The challenge was that the system changed over time. Early in the burn, pressure could be adjusted quickly. As fuel was consumed, responses slowed.

“What we did that was unique was develop a way for a single controller to work across the entire burn cycle, instead of switching between controllers,” Piovoso said. “That improved performance significantly.”

A 2010 flight test of the launch abort system marked a major milestone, particularly for Stroud, who had never before worked on a project that reached that stage. Unlike static tests, where systems remain fixed to the ground and performance is measured through instrumentation, this test unfolded in real flight conditions. It was the first real-world validation that the system would perform as designed.