Titan 23G

The Titan 23G, also written Titan II(23)G and known as the Titan II SLV, was an American medium-lift launch vehicle made from retired LGM-25C Titan II intercontinental ballistic missiles. Martin Marietta won a contract in January 1986 to refurbish fourteen of the missiles to this configuration. The rocket had two liquid-propellant stages, with an Aerojet LR87 engine in the first and an LR91 in the second, and some flights added a Star-37 kick motor. During refurbishment the second stage gained a payload attachment fitting and a fairing, and Delco Electronics upgraded the guidance and control systems. The first launch came on 5 September 1988 with a classified payload for the National Reconnaissance Office, and thirteen rockets flew from Space Launch Complex 4W at Vandenberg Air Force Base, carrying Air Force, NASA and NOAA payloads, until the last flight on 17 October 2003 with a Defense Meteorological Satellite Program satellite. The fourteenth rocket was never launched and is kept at the Evergreen Aviation and Space Museum.