MichSpace

by: Scott Granger - Mission Architectures Intern at Aerojet and MEng Student

This summer I had the opportunity to work at Aerojet in Sacramento, CA. Aerojet is a defense contractor mainly for spacecraft, launch vehicle, and missile propulsion systems. Aerojet has two main competitors – Pratt & Whitney Rocketdyne and ATK. What makes Aerojet so unique is they are the only company that have experience in liquid, solid, and electric propulsion.

I spent 13 weeks in Sacramento, CA working on two main projects. I sat in the Mission Architectures Group which performed the up-front feasibility studies for propulsion systems. The work that is done in this group eventually is the basis for determining the requirements of the system – should the customer give us their business. On the job, I was first introduced to a trajectory simulation tool called POST. POST is a FORTRAN based code (though compiled through an executable) that determines the best trajectory for a launch vehicle based on different propulsion systems. You can set different constraints on the problem to limit, for example, dynamic pressure during staging. A large part of my summer was spent running POST simulations for different launch vehicles composed of many different propulsion systems. Second, I was assigned as the head engineer on a small contract with Sierra Nevada that required 2 weeks of engineering design and analysis. Under this contract, I conducted a trade study for a solid rocket grain geometry that incorporated industry tools that I had never used before. I created grain burn backs for complicated grains and the complete ballistics analysis. The design was put into CAD with performance analysis (Isp, Thrust, maximum pressure, etc) and shipped to the customer.

The location of Aerojet – really located in Rancho Cordova, CA – is somewhat less than desirable. The weather approaches 100 degrees F in the summer and located about 3 hours from San Francisco (the water). Aerojet has historically been an “older” person site, however, it has started to hire younger people over the last 5 years. I encourage anybody interested in mechanical or aerospace design, analysis, or modeling to consider Aerojet.