HOUSTON, TX (Ad Astra PR) – After more than a year of planning and preparation, a team of Ad Astra engineers and physicists, along with NASA engineers participating as part of a technical interchange, completed the company’s first formal preliminary design review (PDR) of the VF-200 engine. The 200 kW “proto-flight” is the company’s first engine planned to be tested in space. The review was conducted on Wednesday, June 26, 2013 at Ad Astra’s research facility near Houston, TX.