A disputed failure

On 26 January 1995 the Long March 2E carrying ApStar 2 (an HS-601) exploded at T+50 seconds and, according to Xinhua, the New China News Agency, the wreckage fell onto a village 7 kilometres downrange killing six people and wounding two dozen others.21,22,2W5 The video of the night launch showed that the explosion had initiated at the top of the vehicle. As the rocket flew through 26,000 feet it had gone supersonic and endured its maximum aerodynamic stress. The China Great Wall Industry Corporation concluded that the 150-kilometre-per-hour wind shear at this altitude that was produced by the winter jetstream over the site in the mountains of southern Sichuan Province had induced a resonance in the payload adapter.26^7 The government-controlled newspaper Ta Kung Pao went further: "The satellite's explosion caused the rocket's explosion, which was entirely the responsibility of the US-made satellite."28 Hughes made its own investigation, and came to a different conclusion.29?30 Since no HS-601 had exploded on any other type of vehicle, after losing Optus B2 Hughes had installed instrumentation to report on the stresses imposed by this type of launch vehicle. Two lines of evidence led Hughes to the conclusion that the shroud had failed. The telemetry from the 'break wire' sensors -which were in place to verify that the shroud had released - indicated that the shroud was disrupted a split second prior to the payload suffering the crushing pressure of being exposed to the airflow. In retrospect, it seemed likely that Optus B2 had been lost in this way. The launch criteria had failed to adequately account for the wind shear. The fact that the Chinese conducted their investigation in private did nothing to placate the insurance industry.31 China was attracting customers by undercutting the fees of its competitors by up to 20 per cent, but the premiums were always high, and were increased significantly after a failure. Because the competition to supply transponders to the rapidly growing Asian market was fierce, APT ordered an HS-376 as a gap-filler, and asked Space Systems/Loral to build a 1300 series for ApStar 2R.32,3V4 The Long March 2E resumed service on 28 November 1995 with AsiaSat 2. Originally set for December 1994, this had been twice postponed, first by the likely explosion of Telstar 402 on 8 September 1994 (both were Lockheed Martin Astro Space 7000 series) and then by the failure of the Long March 2E in January 1995, and was therefore a year late.3V6 It became the first commercial satellite to use the FG-46 solid rocket motor made by the Chinese for the geosynchronous transfer orbit insertion burn.37 (In view of the Chinese insistence that the losses of the HS-601s with American motors had been self-inflicted, AsiaSat was sitting pretty, especially because the shroud had been reinforced too.) On 28 December 1995 a Long March 2E successfully deployed EchoStar 1, which was another 7000 series communications satellite.

geosynchronous transfer orbit. The Chinese intended it to supersede the Long March 2E as its primary commercial launcher.38^9 Unfortunately, within two seconds of lifting off on its inaugural mission on 14 February 1996, it veered off course and fell to Earth, killing several people.40,41,42,43 As the China Great Wall Industry Corporation reported: ''There has been no damage to the launch facilities. However, the living facilities and the nearby residential houses suffered damage to varying

A Long March 3B on display (left) and in flight.

Was this article helpful?

0 0

Post a comment