Artemis would not be possible without Orion, the spacecraft that has carried and sustained the crew on these missions. For seven years, McCullough led vehicle integration for Orion. It was his responsibility to ensure all of the vehicle requirements were correct, necessary, and traceable, and that the systems were built, tested, and certified to create not only a viable spacecraft, but one that was safe for human occupation as well.
“Human rating a new deep-space vehicle is a unique exploration challenge to Artemis,” McCullough said. “Orion was the first in that challenging environment beyond low Earth orbit since Apollo, but human landers, rovers, and lunar habitats are also currently being developed, and they all must work together. If there’s an issue on a cargo or robotic flight, it’s an issue of mission success, not typically life or death as it is with crewed flights.”
With people onboard, the standards and requirements surrounding complex life support, thermal, flight control systems, overall redundancy, vehicle control, aborts, and spacecraft capability are much higher. There are more interfaces as well. For Orion, these standards are the responsibility of the Vehicle Integration Office, which McCullough led during the formative period of spacecraft definition through a 2014 flight test and prep for Artemis I. In this position, he led the charge in getting the vehicle’s mass to an acceptable level. To do this, there must be trade-offs in redundancy and risk acceptance, ensuring risk is even across all parts of the vehicle.