Defense Support Program (DSP) satellites have provided the U.S. Air Force with early warning of ballistic missile launches or above ground nuclear detonations since 1970. This 35-foot-long structural test vehicle includes the infrared sensor Trailblazer component without the associated electronics. Structural test vehicles are full-sized units used to verify that all the components fit together correctly.
In response to the growing threat from nuclear armed Soviet and Chinese ballistic missiles in the 1960s, the U.S. Air Force developed the DSP in great secrecy to replace the space-based infrared Missile Defense Alarm System (MiDAS). A Titan IIIC rocket carried the first DSP satellite, built by TRW (now Northrop Grumman), into orbit on Nov. 6, 1970. Weighing 2,000 pounds, it contained 2,000 infrared detectors that could identify the thermal radiation from rocket engine exhaust plumes of intercontinental ballistic missiles (ICBM) and submarine-launched ballistic missiles (SLBM).
Over nearly 40 years, the DSP satellites underwent numerous improvements to improve their survivability and accuracy, and they added the capability to identify nuclear explosions in support of test ban monitoring. After the Cold War ended, the DSP satellites demonstrated additional flexibility. DSP satellites detected Iraqi Scud missile launches during OPERATION DESERT STORM, and scientists used DSP infrared sensors as part of an early warning system for natural disasters like volcanic eruptions and forest fires.
The USAF placed a total of 23 DSP satellites into orbit with a variety of launch platforms. The first satellites went atop Titan III and IV launch vehicles. The National Museum of the U.S. Air Force has a Titan IV launch vehicle in storage and will place it on display in the future space gallery. The sixteenth satellite, DSP-16, was carried into space aboard NASA's Space Shuttle Orbiter Atlantis in November 1991. The twenty-third and final DSP satellite was also the first operational satellite carried aloft by the Boeing Delta IV Heavy Evolved Expendable Launch Vehicle (EELV) in December 2007. This satellite weighed almost 5,300 pounds and could accommodate 6,000 detectors.
The DSP structural test vehicle on display came to the museum from Northrop Grumman in August 2010.