Don Mahr, Orion Jettison Motor Program Manager

Don Mahr leads a 50-person team at Aerojet Rocketdyne in Sacramento, California, that’s building solid rocket motors for Lockheed Martin Space Systems, prime contractor for NASA’s Orion crew capsule. An Orion capsule would be propelled away from an exploding or crumbling Space Launch System rocket by a stack of three solid rocket motors attached to an aeroshell over the capsule. Within this Launch Abort System, Mahr’s team builds the jettison motor that would, after some harrowing moments, lift the aeroshell and motors off the capsule so that Orion and crew can descend slowly earthward under parachutes. On a normal ascent, the jettison motor will fire before Orion reaches orbit to prepare it for the return trip to Earth. One of the motors will fly in late 2018 on the first SLS launch, likely a crewless trip around the moon, called Exploration Mission 1.

How did you become an aerospace engineer?

My grandfather worked at Aerojet in the late 1960s, through the 1970s and into the ’80s as a welder. I was inspired by that. In high school, physics was a subject I really liked, so I chose to become a mechanical engineer. I went to the University of California, Santa Barbara, where I earned an engineering degree in 2003 and went to work in heating and air conditioning. But that wasn’t nearly as cool as rockets so I went to work for Aerojet Rocketdyne. I started work on the jettison motor as a manufacturing engineer in about 2008 and was responsible for taking the design and creating instruction manuals on how to build it. Then I became the manufacturing lead where I defined and managed the tools, people, schedules that it took to build the jettison motor. In 2014, I became the jettison motor program manager. Now, my job is the whole project, including customer interaction, negotiations, proposals, schedules and contract deliveries.

Imagine the world in 2050; what do you expect to see in space?

I expect by 2050 we will have thermonuclear and solar propulsion technologies fielded for human space applications enabling humanity to colonize Mars. I think the country and humanity are very motivated to go to Mars and beyond because there is much to learn about our existence. Challenging ourselves to push beyond current limitations is what makes us better as a human race.

A smiling man in a dark jacket and striped shirt, standing against a plain white wall.
Don Mahr Credit: Aerojet Rocketdyne

Don Mahr, Orion Jettison Motor Program Manager