Company's Transportation Management Systems Division to Provide SmartBus System for Foothill Transit in West Covina, California

DULLES, Va.--Dec. 5, 2005--   Fleet of 300 Public Transit Vehicles to be Tracked and Managed by Company's GPS Satellite-based System   

Orbital Sciences Corporation (NYSE:ORB) announced today that its Transportation Management Systems division (Orbital TMS) has been awarded an $11.7 million contract by Foothill Transit of West Covina, California. The company will provide a SmartBus(TM) System (SBS) to track and manage Foothill Transit's fleet of 300 public transportation and related vehicles. Orbital TMS will utilize its GPS satellite-based OrbCAD fleet management system to help Foothill Transit achieve its objectives of improving service for its riders and increasing the efficiency of its operations.

Mr. Doran Barnes, Executive Director of Foothill Transit said, "The SBS will support the agency's initiatives to improve operator and passenger safety, and provide accurate and reliable transit information to the riding public. At the same time, the system will allow us to keep our operational costs in check."

Mr. Barnes added, "As the costs to operate public transit systems grow, new technologies provide opportunities to manage these costs while at the same time improve the quality of service to our customers. In addition, we are excited about the possibility of attracting new riders with the availability of real-time data regarding our system. Further, we look forward to using the data generated by the SBS to develop services that more closely meet the needs of the communities that we serve."

The system that Foothill Transit is deploying will include a fully integrated vehicle equipment suite in each of its buses. The benefits of this package include simplified driver operations, ADA regulatory compliant announcements to the public and enhanced passenger security through an advanced video and audio surveillance system. The Foothill Transit fleet is linked to its divisions and headquarters through a wide-area communications radio system that provides a complete assessment of fleet operations and enables rapid response to incidents through the Orbital TMS system.

Among the features the system offers are a Bus Signal Priority (BSP) capability that controls traffic signals to assist buses in maintaining their published schedule. Additionally, Orbital's Advanced Traveler Information System (ATIS) will be included to provide real-time schedule information to the public at major Foothill Transit centers and throughout the regional transit information system.

Mr. David A. Kachemov, Senior Vice President and General Manager of Orbital's TMS division, said, "We are pleased to partner with Foothill Transit in providing the SmartBus System that will assist in providing a more efficient and cost effective transit solution. This system is also scalable and is able to be upgraded, enabling Foothill Transit to plan for the long-term management of services to the riding public."

Mr. Kachemov concluded by adding, "Situational awareness, responsiveness to incidents, service restoration and enhanced customer service are just a few of the benefits that Foothill Transit will realize when the new SBS system is fully implemented."

About Orbital TMS

Orbital TMS is a leading integrator of products for fleet and workforce management, mobile data communications, data management and advanced traveler information systems. TMS provides integrated Computer Aided Dispatch/Automated Vehicle Location (CAD/AVL) solutions for 60 transit and state agency customers in the U.S. and internationally, with units installed or scheduled to be installed on approximately 27,500 vehicles. More information about Orbital TMS can be found at http://www.tms-online.com

About Orbital

Orbital develops and manufactures small space and rocket systems for commercial, military and civil government customers. The company's primary products are satellites and launch vehicles, including low-orbit, geosynchronous and planetary spacecraft for communications, remote sensing, scientific and defense missions; ground- and air-launched rockets that deliver satellites into orbit; and missile defense systems that are used as interceptor and target vehicles. 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. More information about Orbital can be found at: http://www.orbital.com