The Exos, originally designated RM-86 and later PWN-4, was a sounding rocket developed by the University of Michigan and NACA for use by the United States Air Force.
History Developed by the University of Michigan for use by the Air Force Cambridge Research Center, Exos used a three-stage configuration, consisting of a first-stage rocket from an Honest John rocket, a second stage from a Nike-Ajax surface-to-air missile, and a Thiokol XM19 upper stage. It was designated XRM-86 in April 1959, and redesignated PWN-4A in June 1963.
Utilising a rail launcher, the first launch of a full Exos vehicle took place in June 1958, launched from the Wallops Flight Facility. Eight operational launches took place between 1960 and 1965, launched from Eglin Air Force Base.
Launch history Date (UTC) Rocket Launch site Apogee Outcome Mission 26 June 1958 Exos Wallops Island Test launch 25 September 1958 Exos Wallops Island Test launch 19 February 1960 Exos Eglin AFB Chemical release research 11 August 1961 Exos Eglin AFB Ionospheric research 3 August 1962 Exos Eglin AFB Bipolar Probe ionospheric research 25 October 1962 Exos Eglin AFB Ionospheric research 25 July 1963 Exos Eglin AFB Ionospheric research 25 May 1965 Exos Eglin AFB Ionospheric research 2 November 1965 Exos Eglin AFB International Quiet Sun Year aeronomy mission
References