of the stockpile-to-target sequence, the Directorate conducted R&D on techniques for suspension and release of the bombs created by Sandia Laboratory, retardation devices and lay-down delivery of the bombs, as well as monitoring their designs for USAF requirements. In the mid-1950s, the AFSWC's Development Directorate began work on atomic warhead installations in guided missile weapons and the development of warhead support equipment. In January 1955, Douglas Aircraft Company was awarded the development contract for the weapon that became known as the Genie. The Genie was an air-to-air, unguided nuclear-tipped rocket that was designed for arming in the air moments before it was fired. The nuclear warhead of the Genie was a W-25 with a yield of approximately two kilotons. It was the only nuclear rocket to actually be launched and detonated from an aircraft, which took place at 20,000 feet over the Nevada Test Site on 19 July 1957. The original Genie was referred to as the MB-1 and later redesignated the AIR-2A; the carrier aircraft included the F-89J Scorpion, F-101B Voodoo, and F-106A Delta Dart. Other aerodynamic missiles developed at the Development Directorate were the SM-62 Snark, SM-64 Navaho, CIM-10 Bomarc and MGM-1 Matador. The atmospheric tests conducted throughout the 1950s were critical to the definition of nuclear weapons effects for the design of survivable U.S. offensive and defensive weapons systems. Conducted under the auspices of the AEC, each test series was directed by a Joint Task Force appointed by the JCS. In early nuclear test series, the USAF assembled one Air Task Group per test to perform air support and missions. The frequency of tests and these issues justified a permanent group, and the USAF looked to AFSWC to fill the requirements. In response, in 1956 AFSWC established the 4950th Test Group (Nuclear) to serve as a permanent USAF Air Task Group for atmospheric testing, replacing the 4925th Test Group (Atomic), which then focused on the aircraft/weapon marriage mission. In 1958, efforts were underway between the United States and Soviet Union to agree on a moratorium for atmospheric nuclear testing. The anticipated limitations on determining weapons effects inspired efforts by the Special Weapons Center and Sandia Corporation to develop methods of simulating nuclear effects with non-nuclear techniques. In 1962, Kirtland AFB and Sandia personnel participated in Operation Dominic, a series of atmospheric and subsurface tests in the Pacific. They were the last such tests conducted before the Partial