The July 26 test stand accident at the Mojave Air and Space Port, Calif., that killed three Scaled Composites employees and injured three others stunned the community of entrepreneurial companies there and around the United States.

Scaled Composites founder and president Burt Rutan said during a July 26 press conference that the accident occurred during propellant flow testing on SpaceShipTwo, the first of a fleet of suborbital space tourism vehicles Scaled Composites plans to build as part of a joint venture with Sir Richard Branson’s Virgin Group.