DFH-2A 1, 2, 3, 4, 5 (STTW, ChinaSat, ZX 1, 2, 3, 4) (original) (raw)

DFH-2A [CAST]

China operated a constellation of three Dongfanghong DFH-2 (aka STTW = Shiyan Tongbu Tongxing Weixing) communications satellites in GEO for domestic needs. Designed, manufactured, and launched by indigenous means, the modest DFH-2 Dongfanghong DFH-2 (Dong Fang Hong - The East is Red) space craft were analogous to 1960's era Western GEO satellites (e.g., INTELSAT 3), although slightly heavier.

With an on-orbit mass of 441 kg (compared to 433 kg for the earlier satellites), DFH-2Aspacecraft were successfully placed in GEO in March, 1988, December, 1988, and February, 1990, and positioned at 87.5 degrees E, 110.5 degrees E, and 98 degrees E, respectively. All three satellites remained on station at the end of 1994. A fourth DFH-2 was lost on 28 December 1991 when its CZ-3 upper stage failed to reignite. DFH-2A-1, 2A-2, 2A-3 were later renamed ChinaSat-1, ChinaSat-2 and ChinaSat-3, respectively.

The DFH-2A was a spin-stabilized, drum-shaped satellite with a diameter of 2.1 m and a height of 3.1 m. The communications payload consisted of only two 6/4 GHz transponders with an output power of 10 W. The total electrical power capacity was assessed to be about 300 W (the first two experimental satellites were rated at 284 W).

Prior to 1993 all DFH satellites were operated by the military. All DFH-2As had exhausted fuel and halted operation by the early 1990s.