08/15/2008. Eclipse Aviation is using the Eclipse Concept Jet (ECJ) to analyze the growing single-engined jet marketplace and to gain customer reaction. The ECJ was conceived in December 2006 and Swift Engineering of San Clemente, California was contracted for the design. Airframe construction was done by BaySys Technologies of Onancock, Virginia, at a hangar at nearby NASA Wallop Flight Facility.

To preserve its anonymity the ECJ was registered as the Swift Engineering Mark 400. Code named Speed Bird, it made its first flight on July 2, 2007, just 200 days after formal design began and three weeks later it had a surprise debut at the EAA AirVenture 2007 Convention at Oshkosh, Wisconsin, on July 23.