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Encyclopedia entry

P

Program

Original archive entry. The text, images and links below are kept as they were written.

P designations were given to a series of classified US military technology and operational satellites launched from the 1960's.

Subtopics

Chronology

7 events

1961 February 25

00:13 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC26B. LV Family: Jupiter. Launch Vehicle: Juno II. FAILURE: Third Stage failed to ignite.. Failed Stage: 3.
  • Explorer - . Payload: S-45. Mass: 34 kg (74 lb). Nation: USA. Agency: NASA. Program: Explorer. Class: Astronomy. Type: Solar satellite. Spacecraft Bus: P. Spacecraft: P-14. Decay Date: 1961-02-24 .

1961 March 25

15:17 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Thor. Launch Vehicle: Thor Delta.
  • Explorer 10 - . Payload: P-14. Mass: 35 kg (77 lb). Nation: USA. Agency: NASA. Program: Explorer. Class: Astronomy. Type: Solar satellite. Spacecraft Bus: P. Spacecraft: P-14. Decay Date: 1961-06-30 . USAF Sat Cat: 98 . COSPAR: 1961-Kappa-1. Apogee: 181,100 km (112,500 mi). Perigee: 221 km (137 mi). Inclination: 33.00 deg. Period: 5,013.90 min. Magnetic field data. Decay date suspect Spacecraft engaged in research and exploration of the upper atmosphere or outer space (US Cat B)..

1961 May 24

19:48 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC26B. LV Family: Jupiter. Launch Vehicle: Juno II. FAILURE: Second Stage failed to ignite.. Failed Stage: 2.
  • Explorer S-45A - . Payload: S-45A. Mass: 33 kg (72 lb). Nation: USA. Agency: NASA. Program: Explorer. Class: Astronomy. Type: Solar satellite. Spacecraft Bus: P. Spacecraft: P-14. Decay Date: 1961-05-24 .

1975 April 13

00:51 GMT - . Launch Site: Vandenberg. Launch Complex: Vandenberg SLC3W. LV Family: Atlas. Launch Vehicle: Atlas F. FAILURE: First stage failure due to explosion in flame pit at lift-off.. Failed Stage: 1.
  • P 72-2 - . Nation: USA. Agency: USAF. Class: Technology. Type: Military technology satellite. Spacecraft Bus: P. Spacecraft: P 72. Decay Date: 1975-04-12 .

    Space Test Program flight P72-2 was launched; it carried two infrared radiometers and three other payloads. The launch failed when the Atlas F launch vehicle malfunctioned. A lack of deluge water and collection in the flame bucket of a kerosene/liquid oxygen gel led to the explosion of the gel on lift-off, damaging one of the Atlas engines and leading to complete engine failure during the ascent.

1976 May 22

07:42 GMT - . Launch Site: Vandenberg. Launch Complex: Vandenberg SLC5. LV Family: Scout. Launch Vehicle: Scout B-1.
  • P 76-5 - . Mass: 73 kg (160 lb). Nation: USA. Agency: USAF STP. Class: Technology. Type: Communications technology satellite. Spacecraft Bus: P. Spacecraft: P 76. USAF Sat Cat: 8860 . COSPAR: 1976-047A. Apogee: 1,044 km (648 mi). Perigee: 981 km (609 mi). Inclination: 99.60 deg. Period: 105.40 min.

    A Scout vehicle carrying a Space Test Program spacecraft was successfully launched from SLC-5 at the Western Test Range. The spacecraft, Flight P76-5, carried a wideband signals experiment sponsored by the Defense Nuclear Agency. Communications propagation experiments.

1978 January 3

  • Spacecraft for the Satellite Infrared Experiment (SIRE). - . Spacecraft Bus: P. Spacecraft: P80-2.

    Lockheed Missiles and Space Company was awarded a $34 million contract to build a spacecraft for the Satellite Infrared Experiment (SIRE), designed to measure long wave infrared signatures. The spacecraft would also carry two secondary payloads - a space sextant and a sensor that would measure the isotopic composition of solar flares.

1979 April 26

  • Satellite Infrared Experiment terminated - . Spacecraft Bus: P. Spacecraft: P80-2.

    SAMSO terminated the SIRE (Satellite Infrared Experiment) contract with Lockheed because of large cost overruns. The SIRE payload was to have been launched on flight P80-2 and was to have measured the long wave infrared signatures of space objects against the stellar background. SAMSO began to develop a program to fly the SIRE sensor on space shuttle sortie missions around the mid-1980s.