Monday, 7 December, 2009

PRC Missile and Space Forces 5

Two years after the first successful launch of the Long March 2E, the PRC successfully launched the Long March 3A, a cheaper, higher performance rocket that would better meet both its military and commercial geosynchronous launch requirements. The Long March 3A was the first of a family of Long March 3A, 3B and 3C rockets.

The Long March 3A family of rockets uses a strengthened Long March 3 first stage. In the case of the Long March 3B and 3C, this permits the mounting of additional strap-on boosters. The Long March 3A, 3B, and 3C rockets also use a new, lighter weight, and cheaper inertial measurement unit. Furthermore, these rockets employ large "hammerhead" fairings to protect their satellite payloads. The launch history of the Long March 3A, 3B, and 3C rockets is listed below. The failure analysis of the Long March 3B launch carrying the Intelsat 708 satellite manufactured by Loral, is discussed in the chapter of this Report entitled Satellite Launches in the PRC: Loral.



Comparison of Two Different Inertial Measurement Units

Used in Guidance System of Long March Rockets59

Features of the Inertial Measurement Unit Used in the Guidance System of:

LM 2C/2E/3LM 3A/3B/3C

Number of Gimbals34

Number of Gyroscopes32

Number of Accelerometers33

Number of Torque Motors for Each Gimbal21

Dimensions (mm)500 x 600 x 800300 x 300 x 400

Mass (kg)14048

Maiden Flight1974 on Long March 2C1994 on Long March 3A

Manufactured by CALT (LM 2C/2E) CALT CAST (LM 3)
The PRC's Commercial Space Launch Program

The PRC's entry into the commercial space launch market coincided with a dark period for the U.S. launch industry that included the 1985 and 1986 launch failures of several Delta and Titan expendable rockets, and the 1987 explosion of the Space Shuttle Challenger. At the time of the Challenger accident, the U.S. space launch industry was in the midst of a plan to phase out all expendable rockets in favor of the Space Shuttle, which was projected to be more economical.60 But that plan was cancelled with the

Challenger explosion. Instead, the United States imposed a hiatus in shuttle launches until September 1988, and a permanent decision that the Space Shuttle would not be used to launch commercial payloads.61

The lack of available U.S. commercial space launch capacity forced satellite manufacturers to seek alternative launch providers. The Soviet Union had the capacity to launch commercial satellites, but U.S. policy would not support the launching of U.S.-manufactured satellites on Soviet rockets. The European consortium of Arianespace had a rocket, but no extra capacity. This left the PRC as the only alternative for launching geosynchronous communications satellites.

In 1987, the United States viewed the PRC as a counterbalance to Soviet military power in Asia. Accordingly, the "Green Line" policy had been adopted to permit some technology transfers to the PRC, while limiting transfers of technologies that could improve the PLA's ballistic missile and anti-submarine warfare capabilities.62 In 1988, President Reagan agreed to allow the PRC to launch U.S.-manufactured satellites on the condition that the PRC sign three bilateral agreements with the U.S. on competitive pricing, liability, and the protection of U.S. technology. 63

The PRC's first success in the commercial market occurred in 1987. In that year, Matra of France contracted with the PRC to place a scientific payload in orbit, using a Long March 2C rocket. These French scientific experiments were launched on August 5, 1987 aboard a PLA military photo-reconnaissance satellite. The recoverable capsules of the PLA's reconnaissance satellites made them an ideal platform for microgravity experiments.64

The PRC's first commercial launch of a U.S.-manufactured communications satellite occurred on April 7, 1990. The Asiasat?a Hughes HS 376 model satellite? was launched into orbit aboard a Long March 3 rocket.65

From that point, in addition to their military launch schedule, the PRC has attempted 28 launches of Western-manufactured satellites.66 Of these satellites, 27 were U.S-manufactured: only the French-manufactured Sinosat, launched successfully on July 18, 1998, was produced by a non-U.S. manufacturer. 67 Twenty-three of the PRC's attempts to launch U.S. satellites were successful. Four have ended in failure.68 These four failures are detailed below.

PRC Commercial Launch Failures

SatelliteLaunch DateRocketFailure Mode

Optus B2Dec. 21, 1992Long March 2EFairing collapse

Apstar-2Jan. 25, 1995Long March 2EFairing collapse

Intelsat 708Feb. 15, 1996Long March 3BInertial measurement

unit malfunction

Chinasat 7Aug. 18, 1996Long March 3Third stage malfunction

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