Space

Orbital Successfully Launches Target Vehicle For MDA's Aegis Ballistic Missile Defense Test

Company Completes 45th Target Launch in Last 10 Years

(Dulles, VA 16 December 2003) - Orbital Sciences Corporation (NYSE: ORB) announced today that it successfully launched the suborbital rocket that served as the target vehicle for the recent test of the U.S. Missile Defense Agency's (MDA) Aegis Ballistic Missile Defense (Aegis BMD) program. The launch of Orbital's Target Test Vehicle (TTV) originated from the island of Kauai, Hawaii on December 11. Orbital's role in the test was to supply the TTV rocket and conduct the launch operations under contract to the U.S. Air Force Space and Missile Systems Center. The pre-launch design, engineering and production work for the TTV mission was accomplished by Orbital's Launch Systems Group at its facility in Chandler, Arizona.

"With the success of the TTV launch in support of MDA's Aegis BMD program, Orbital continues to demonstrate the operational reliability of our target vehicles, which are critical to the testing of the country's missile defense systems," said Mr. Ron Grabe, Executive Vice President and General Manager of Orbital's Launch Systems Group. "In the last ten years, Orbital has carried out 45 missile defense target vehicle launches, by far the most target missions of any company during that period, and we completed them with a 98 percent success rate," Mr. Grabe concluded.

Orbital is one of the country's most experienced developers and operators of missile defense-related launch vehicles. The company supports virtually all of the country's major missile defense programs with cost-effective and highly reliable target vehicles. In addition to the Aegis BMD, Orbital's target vehicles are used to test MDA's Ground-based Midcourse Defense system (GMD) and the U.S. Army's PAC-3 and THAAD interceptors and its the Critical Measurements Program. Orbital is also developing a new sea-skimming supersonic target vehicle for the U.S. Navy's ship self-defense systems.

In addition to target vehicles, Orbital has rapidly become one of the country's leading suppliers of missile defense interceptor boosters, supporting both the GMD and Kinetic Energy Interceptors (KEI) programs. As part of a Boeing-led team, Orbital is the primary supplier of test and operational interceptor boosters for MDA's GMD system, which is scheduled to begin initial deployments in 2004. In addition, a member of a Northrop Grumman-led team, Orbital will conduct booster design, development, test, and early-production for MDA's KEI system beginning next year and continuing through the end of the decade.

About Orbital
Orbital develops and manufactures small space systems for military, commercial, and civil government customers. The company's primary products are launch vehicles and satellites, including missile defense boosters that are used as interceptor and target vehicles, ground- and air-launched rockets that deliver satellites into orbit, and low-orbit, geostationary and planetary spacecraft for communications, remote sensing and scientific missions. Orbital also offers space-related technical services to government agencies and develops and builds satellite-based transportation management systems for public transit agencies and private vehicle fleet operators.

Contact: Barron Beneski, 7034065000, beneski.barron@orbital.com