Losing Optus B

The Long March 2E was the Long March 2C two-stage launch vehicle augmented by four liquid strap-ons. Able to put 9.5 tonnes into low orbit or insert 3.5 tonnes into geosynchronous transfer orbit, it had a capability approaching that of the Ariane 4 or Proton.10,n On its maiden flight on 16 July 1990 it carried Pakistan's first satellite, Badr. On 14 August 1992 it deployed Optus B1, which was an HS-601 for the Australian Telecommunications Company (formerly Aussat, now Optus). As it was a two-stage vehicle that released its payload in low orbit, a kick-motor was required to insert the satellite into geosynchronous transfer orbit, and the HS-601s used the PAM-D2, which used a Thiokol Star 63 solid rocket motor.12 When a Long March 2E released its payload on 21 December 1992, the Optus B2 satellite failed to respond. On reviewing footage of the ascent, an anomalous plume was seen to emerge from the shroud at T + 48 seconds. It appeared that the payload had suffered a fatal mishap at the moment the vehicle was subjected to the greatest aerodynamic stress. In the absence of proof that the shroud had failed, the Chinese decided that the interface between the upper stage and the payload (which used parts from both Hughes and the China Great Wall Industry Corporation) was insufficiently robust and had suffered a resonance that destroyed the vehicle.13,1V5 The Long March 2E returned to service on 27 August 1994 with Optus B3.16 Although it had blamed the payload adapter for the loss of Optus B2, on 20 January 1995 the Chinese acceded to

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A Long March 2E lifts off with an Optus satellite.

a request from the EchoStar Communications Corporation to reinforce the shroud of the Long March 2E prior to launching that company's satellite.17

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