In October 1985, the Chinese Ministry of Astronautics revealed its ambition to enter the international commercial space market, by offering foreign customers the service to launch their geostationary communications satellites using Long March launch vehicles.
However, China’s only launch vehicle for high-orbit missions, the Long March 3, could only loft 1,400 kg payload to Geostationary Transfer Orbit (GTO), far less than the typical mass of Western-made communications satellites of the time. As a result, CLAT proposed in 1986 its Long March 2E concept.
The 2E model used the two-stage Long March 2C as its core stage, added with four liquid-propellant strap-on boosters, which increased the vehicle’s payload capacity from 2,400 kg to 9,500 kg to LEO. When coupled with a solid or LOX/LH2 upper stage, the launch vehicle could loft 3,000 to 4,800 kg payload to GTO.
To increase the vehicle’s propellant capacity, the first-stage of the core stage was stretched by 4.6 m, and the second-stage by 5.2 m. The satellite and the upper stage were housed inside an enlarged payload fairing 10.5 m in length and 4.2 m in diameter. The overall height of the launch vehicle stack was 50 m.
Other improvements on the Long March 2E included:
- Improved engines with increased thrust and Isp;
- Propellant management system on the second-stage;
- Flight-control system and solid control rockets on the second-stage;
- Replacing the mesh-bar inter-stage section with a ring design featuring flame deflection windows;
- Digital flight-control system replacing the original analogue design;
- New telemetry system with higher data transmission capacity.
In September 1987, China Great Wall Industries Corporation (CGWIC) was selected as the contractor for the launch of two Hughes communications satellites for Australian telecommunications company Optus. CALT was sub-contracted for the development of the Long March 2E launch vehicle, though at the time the vehicle only existed on paper.
Over the next 18 months, CALT moved heaven and earth to meet the July 1990 target date for a test flight of the launch vehicle. Engineering development of the Long March 2E began in October 1988, and a new launch pad began construction at the same time at Xichang Satellite Launch Centre (XSLC) in the central province of Sichuan. Against all odds, the launch vehicle made its maiden flight successfully on 16 July 1990, placing a dummy Hughes HS-601 communications satellite and a Pakistani experimental satellite Badr-A into orbit.
The first mission with an operational satellite was scheduled for 22 March 1992. However, the launch vehicle carrying the US-made Optus B1 communications satellite failed to ignite. It took the ground crew 39 hours to secure the vehicle and retrieve the satellite. The same launch vehicle was put back on the launch pad five months later, and successfully placed the Optus B1 satellite into orbit on 14 August.
Four months later, the second satellite Optus B2 was launched from Xichang atop a Long March 2E on 21 December. However, the satellite exploded inside the payload fairing 45 seconds into the flight, though the rocket continued flying and delivered the debris of the satellite into the scheduled orbit. Later investigation suggested that the accident was caused by wind shear. The Long March 2E resumed flight on 28 August 1994, successfully orbiting Optus B3.
Disaster stroke again five months later on 26 January 1995, when a Long March 2E carrying the Hughes-built APStar 2 communications satellite exploded approximately 50 seconds after lift-off. The failure was believed to have been caused by strong horizontal wind-shear once the vehicle had cleared the mountains surrounding the launch site.
Exactly which side was responsible for the failure was inconclusive. Chinese engineers believed that the wind-shear had caused a mechanical resonance that caused an explosion in the satellite’s apogee kick stage, while Hughes engineers believed that the vehicle’s payload fairing collapsed under the force of the wind-shear due to design fault.
Following the accident, modifications were made to the launch vehicle’s fairing design. The next two flights of the Long March 2E later in the year were both successful. However, the launch vehicle was then withdrawn from service after only 7 missions.
