Just came across this about STS-4. Skip to the last sentence:
Aviation Week & Space Technology
June 7, 1982
Shuttle Flight Plan Paced by Payloads
BYLINE: By Craig Covault
SECTION: SPACE TECHNOLOGY; Pg. 82
LENGTH: 3341 words
DATELINE: Washington
Flight plan for space shuttle Mission 4 astronauts Navy Capt. Thomas K. Mattingly and Henry W. Hartsfield will be paced by operation of the U. S. Air Force multidisciplinary payload, manipulator arm operations and management of biological materials processing in zero-g.
As in the third mission, the planned 168-hr. flight, spread over eight days, has orbiter thermal testing as a primary objective. Liftoff is scheduled for 11 a. m. June 27.
The mission is a pathfinder for space shuttle defense operations from the standpoint of payload support at Kennedy Space Center and secure mission operations at the Johnson Space Center and the USAF satellite control facility, located in Sunnyvale, Calif.
Key elements of Defense Dept.'s first shuttle payload are:
* Cryogenic infrared radiance instrumentation for shuttle (Cirris) -- The payload consists of a barrel-shaped, cryogenically cooled infrared sensor developed by the Air Force Geophysical Laboratory and Utah State University. The sensor will examine the Earth limb and atmospheric background to provide data supporting an increasing number of military surveillance systems incorporating infrared technology (AW&ST Mar. 15, p. 13; June 22, 1981, p. 15). The data will be used to establish criteria for signature identification of Soviet air-breathing and missile threats that could be observed by infrared sensors.
Cirris Research
Space shuttle payload bay contamination environment also will be researched by the Cirris instrument and there is concern that the instrument could see significant particulate contamination surrounding the orbiter if the orbiter characteristics found in initial Mission 3 data recur (AW&ST May 24, p. 53).
* Horizon ultraviolet program -The horizon ultraviolet sensor (AW&ST June 23, 1980, p. 47) will provide similar data on the ultraviolet characteristics of Earth's horizon for future military surveillance applications requiring this wavelength. There has been increasing interest in ultraviolet for use in missile early warning systems. The sensor also is sponsored by the Air Force Geophysical Laboratory.
* Sheath wake and charging experiment -- This geophysical laboratory experiment will characterize further the electrical environment present in the payload bay.
* Passive cosmic ray detector -The Cambridge Research Laboratory instrument will record the cosmic ray bombardment on the orbiter in space.
* Shuttle effects on plasmas in space --The Naval Research Laboratory experiment will characterize further the space plasma surrounding the orbiter, investigations initially carried out by the plasma diagnostics package on the third mission.
* Space sextant -This 43-lb. Martin Marietta instrument is designed to provide unmanned spacecraft with navigation data in the absence of extensive ground support. It is receiving its first space test on this mission. The system is designed to provide a navigation accuracy of 820 ft. and an attitude accuracy of 0.4 arc-sec. It is designed to provide five years of operational life.
* Pallet alignment modeling experiment -- This is to test the ability to predict and maintain the alignment of pallets carrying shuttle defense instrumentation. Lockheed has been involved in the integration.
U. S. Air Force earlier was considering a standard sortie support system, such as General Electric's standard test rack configuration, to support the instruments. Those plans have been dropped. The hardware is in storage at General Electric's Valley Forge, Pa., facility with no space utilization in sight.
The first Defense Dept. shuttle payload is devoted to obtaining scientific data that will be fed into various defense programs. USAF had earlier wanted the mission to carry a large military imaging reconnaissance film camera in the payload bay.
Military Reconnaissance
The plan to test actively the concept of utilizing the space shuttle as a manned military reconnaissance sortie vehicle was not approved by congressional intelligence officials, and USAF moved its attention away from using Mission 4 for anything other than scientific data gathering to enhance future defense systems.