Space Test Program Payloads

1974 April 10

20:20 GMT - . Launch Site: Vandenberg. Launch Complex: Vandenberg SLC4E. LV Family: Titan. Launch Vehicle: Titan IIID.

• S73-7 Cal Balloon - . Payload: OPS 6935 / P 73-7. Mass: 60 kg (132 lb). Nation: USA. Agency: USAF AFSC. Spacecraft Bus: Space Test Program Payloads. Spacecraft: S73-7 Cal Balloon. Decay Date: 1974-07-28 . USAF Sat Cat: 7244 . COSPAR: 1974-020B. Apogee: 247 km (153 mi). Perigee: 148 km (91 mi). Inclination: 94.40 deg. Period: 88.50 min. Space Test Program flight S73-7 was launched. The launch was successful but the mission failed when the payload -an infrared calibration balloon - failed to deploy..

1974 October 29

19:30 GMT - . Launch Site: Vandenberg. Launch Complex: Vandenberg SLC4E. LV Family: Titan. Launch Vehicle: Titan IIID.

• SESP 73-5 - . Payload: P 73 5 / OPS 8452. Mass: 260 kg (570 lb). Nation: USA. Agency: USAF. Class: Technology. Type: Military technology satellite. Spacecraft Bus: Space Test Program Payloads. Spacecraft: SESP. Decay Date: 1975-05-26 . USAF Sat Cat: 7499 . COSPAR: 1974-085C. Apogee: 2,888 km (1,794 mi). Perigee: 150 km (90 mi). Inclination: 96.90 deg. Period: 116.30 min. Space Test Program flight S73-5 was successfully launched. This was the first of three launches to be made under the Small Secondary Satellite (S3) project. Space craft engaged in investigation of spaceflight techniques and technology (US Cat A)..

1976 January 30

• Contract for Space Test Program Flight P78-1. - . Spacecraft Bus: Space Test Program Payloads. Spacecraft: Solwind. Effective on this date, Ball Brothers Research Corporation was awarded a $10.3 million contract to develop a space vehicle system for Space Test Program Flight P78-1..

1976 March 1

• Contract for Space Test Program Flight P78-2. - . Spacecraft Bus: Space Test Program Payloads. Spacecraft: SCATHA. Effective on this date, Martin Marietta "Corporation was awarded a $12.36 million contract to develop a spacecraft for Space Test Program Flight P78-2..

1978 November 6

• Space Test Program budgetary deficit. - . Spacecraft: Space Test Program Payloads. The Director of the Space Test Program briefed HQ AFSC on a budgetary deficit that the program was facing. The deficit amounted to $8.8 million in FY 1979..

1979 January 30

21:42 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17B. LV Family: Thor. Launch Vehicle: Delta 2914.

• SCATHA - . Payload: P 78-2. Mass: 360 kg (790 lb). Nation: USA. Agency: USAF. Class: Technology. Type: Communications technology satellite. Spacecraft Bus: Space Test Program Payloads. Spacecraft: SCATHA. Completed Operations Date: 1991-05-28 . USAF Sat Cat: 11256 . COSPAR: 1979-007A. Apogee: 42,860 km (26,630 mi). Perigee: 28,018 km (17,409 mi). Inclination: 10.20 deg. Period: 1,418.40 min.

  Flight P78-2 was successfully launched by SAMSO's Space Test Program. The mission was designated SCATHA (Spacecraft Charging at High Altitudes) and gathered data on the build-up of electrical charges on satellites operating at geosynchronous altitude. It was sponsored jointly by NASA and the Air Force. Spacecraft charging experiments. The SCATHA spacecraft had two charged particle injection systems, one of which was the Satellite Positive-Ion-Beam System (SPIBS). This was a xenon ion source which included some of the technologies used in thrusters: however, the discharge chamber was not performance optimized as was done with ion engines. Maximum operating power was 0.045 kW, and the ion source could produce a thrust of about 0.14 mN at a specific impulse of 350 s. Ions could be ejected at 1 keV or 2 keV. Neutralization was accomplished by a tantalum filament. The specific impulse was low because there was no attempt to optimize the propellant efficiency. The SPIBS system was ground-tested for a period of 600 hours. The SCATHA spacecraft was placed in a near geosynchronous orbit. Ion beam operations were performed intermittently over a 247 day period. The SCATHA flight demonstrated that a charged spacecraft, and the dielectric surfaces on it, could be safely discharged by emitting a very low energy (<50 eV) neutral plasma -- in effect shorting the spacecraft to the ambient plasma before dangerous charging levels could be reached. As of 28 August 2001 located at 153.98 deg W drifting at 4.513 deg E per day. As of 2007 Mar 8 located at 19.65W drifting at 4.513E degrees per day.

1979 February 24

08:24 GMT - . Launch Site: Vandenberg. Launch Complex: Vandenberg SLC3W. LV Family: Atlas. Launch Vehicle: Atlas F/OIS.

• Solwind (P 78-1) - . Payload: P 78-1. Mass: 1,331 kg (2,934 lb). Nation: USA. Agency: USN. Class: Earth. Type: Magnetosphere satellite. Spacecraft Bus: Space Test Program Payloads. Spacecraft: Solwind. Decay Date: 1985-09-30 . USAF Sat Cat: 11278 . COSPAR: 1979-017A. Apogee: 317 km (196 mi). Perigee: 310 km (190 mi). Inclination: 97.80 deg. Period: 90.80 min.

  Atlas booster 27F successfully launched Space Test Program Flight P78-1 from Space Launch Complex 3W, Vandenberg AFB, California. The primary payload on the spacecraft was a gamma spectrometer sponsored by the Defense Advanced Research Projects Agency (DARPA). Ionosphere and magnetosphere studies; destroyed on 13 September 1985 (while still functioning) as part of an American ASAT test.