TDRS 9

USA

Spacecraft nº:

USA satellite nº:

Also called TDRS I

Launch data:

Designation	27389 / 02011A
Launch date	08 Mar 2002 - 22:59 UT
Launch site	CC, SLC-36A
Launch vehicle	Atlas 2A (AC-143 / #137)
Mission	Communications, Data relay
Geostationary orbit on:
Perigee / Apogee	km
Eccentricity
Inclination	deg
Period	min
Location	151°W

To be tested from 151°W.

Four days after launch, an anomaly occured with one of the 4 fuel tanks, pressure has dropped: a faulty valve prevented helium to pressurize a tank. Once a neighboring tank was empty, helium could be transfered to the faulty tank and little burns were possible. The satellite finally arrived in GEO in early Oct 2002 after months of effort! Enough fuel is available for the 15-year lifetime.

Specifications:

Prime contractor	Hughes
Platform	HS-601 modified
Mass at launch	3180 kg
Mass in orbit	1670 kg
Dry mass	1500 kg
Dimension	stowed: 2.7 x 3.4 x 8.4 m (8 meters with the antenna folding)
Solar array	21 m span
Stabilization	3-axis
DC power	2300 W
Design lifetime	11 years

The 2 main (east-west) antennas are steerable single-access antennas that can simultaneously transmit and receive at S-band and either Ku- or Ka-band, supporting dual independent two-way communication. The selection of Ku- or Ka-band communications is done on the ground. Receive data rates are 300 megabits/second at Ku- and Ka-band, and 6 Mbps at S-band. The spacecraft carries additional capability for Ka-band receive rates of up to 800 Mbps. Transmit data rates are 25 Mbps for Ku- and Ka-band, and 300 kilobits/second for S-band. In addition, an S-band phased array antenna can receive signals from five spacecraft at once, while transmitting to one. There is no C-band on these satellites.

Telemetry: 2211.5 MHz (0.5, 1 or 4 kbps)
Telemetry: 2206.5 MHz (0.5, 1 or 4 kbps)
Telemetry: 13731 MHz
Command: 2035.96 or 2031.81 MHz (2 kbps)
Command: 14786 MHz (+ 15150 MHz)

Ref: #7, #15, #78a - update: 06.04.09