The thrill of watching a successful ground test of a rocket was enjoyed by Orbital Sciences Corporation [NYSE: ORB] when they completed the full-scale pathfinder ground operations of the Minotaur IV space launch vehicle in preparation for its inaugural flight that is currently scheduled to take place in early 2009. The ground testing activities included the assembly of a full-scale Minotaur IV rocket, using inert rocket motors and flight-qualified structures to fully validate all interfaces with the booster, ground support equipment and facility structures.  It also serves as a rehearsal of all hazardous lifting operations, a fit-check for all vital rocket and ground interfaces, a final test of the mission's ground support equipment, and a checkout of vehicle integration procedures.  The extensive pre-launch activities also enhance training of the launch crew and facility personnel.

The pathfinder operations were overseen by representatives from the U.S. Air Force organizations that will play critical roles in the Minotaur IV launch operations. These include; the U.S. Air Force Space and Missile Systems Center, the U.S. Air Force Space and Development Test Wing, and 30th Space Wing based at Vandenberg Air Force Base (VAFB) in California. The Spaceport Systems International launch pad at VAFB will be the launch site for all three Minotaur IV missions planned in 2009.

"The completion of our pathfinder ground operations test is a major step forward as we proceed toward the inaugural launch of the Minotaur IV launch vehicle," said Mr. Lou Amorosi, Orbital's Vice President with responsibility for its entire Minotaur launch vehicle product line.  "In conjunction with our customers and partners that will play vital roles during actual launch operations, we are taking a very methodical and comprehensive approach to ensuring that all aspects of the launch vehicle preparations, ground operations and range safety systems are meticulously planned, rehearsed and reviewed."

During the pathfinder, the various vehicle stages and components were transported, assembled and stacked at the launch site. Once the vehicle was fully assembled, a day-of-launch shelter rollback was rehearsed. Subsequent to those operations, abort operations were also rehearsed and timed before the vehicle was de-stacked and transported back to the integration facility.

The ground operations also included rehearsal of spacecraft encapsulation procedures within the launch vehicle fairing. The Minotaur IV design provides for separate spacecraft encapsulation, which is an enabling procedure for Operationally Responsive Space (ORS) missions, by streamlining the time and sequence of spacecraft encapsulation. Spacecraft can be selected for launch, mated, encapsulated and transported to the launch site independent of other launch vehicle or range operations.