Atlas 5 551 lifts off from the launch pad for New Horizons mission. Photo: ULA.

The U.S. Air Force announced it has awarded United Launch Alliance (ULA) a contract to launch the Space Test Program-3 (STP-3) mission. This contract resulted from a competitive award under the Air Force’s Phase 1A procurement strategy and is valued at $191.1 million.

The STP-3 mission is scheduled to launch in the summer of 2019 from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. This mission will launch aboard an Atlas 5 551 vehicle.

ULA also launched the first Space Test Program mission in March 2007. The launch marked the first Air Force Evolved Expendable Launch Vehicle (EELV) mission on an Atlas 5 and the first Atlas 5 mission for ULA.

The STP-3 mission consists of a primary space vehicle (STPSat 6) and an integrated propulsive EELV Secondary Payload Adapter (ESPA) holding up to six payloads (IP-ESPA). The STPSat 6 space vehicle will host the National Nuclear Security Administration (NNSA) Space and Atmospheric Burst Reporting System 3 (SABRS-3) payload, and the NASA Laser Communications Relay Demonstration (LCRD) payload. The Department of Defense (DOD) also manifested seven science and technology payloads.