Transfer of Tracking and Data Relay Satellite finally agreed after performance shortfall
Control of the Boeing-built TDRS-H tracking and data relay satellite, launched by an Atlas booster in June last year, has finally been transferred to NASA.
The transfer had been delayed because of inadequacies on the multiple-access phased-array antenna which resulted in five of the 18 TDRS-H communications services falling short of specifications. The spacecraft provides S-, Ku-and Ka-band communications services.
NASA and Boeing have tentatively agreed on a settlement, the terms of which are being finalised. "We are certain that a repeat of this performance shortfall will not occur," says Randy Brinkley, president of Boeing Satellite Systems. High data rates using the single-access antennas are not affected.
The remaining "switchboard in the sky" satellites in the programme, TDRS-I and J, are scheduled for launch in October this year and October 2002. These satellites will double the capacity of data transmission and provide nearly continuous communications between the Earth, the Space Shuttle, the International Space Station and dozens of unmanned scientific satellites.
The first six TDRS satellites were built by TRW, the first being launched in 1983. The H, I and J satellites add Ka-band single-access capability to the fleet, allowing high data rates at more favourable frequencies with less susceptibility to interference from the increasingly busy radio environment.
Source: Flight International
