TDRS TDRS
Credit: Lockheed-Martin
American military communications satellite. Satellite communications network, for use by Shuttle and US military satellites. Communication satellite built by TRW for NASA, USA. Launched 1983 - 1993.
AKA: Tracking and Data Relay Satellite. Status: Operational 1983. First Launch: 1983年04月04日. Last Launch: 1995年07月13日. Number: 7 . Gross mass: 2,240 kg (4,930 lb). Span: 17.40 m (57.00 ft).
When first launched, the TDRS satellites were the largest, most sophisticated communications satellites ever built. The seventh vehicle in the series was ordered as a replacement when TDRS-2 was lost in the Challenger accident.
The hexagonal spacecraft and payload modules were 3-axis stabilized. The zero momentum biased control system used reaction wheels and Earth sensors. Two solar arrays provided 2 kW BOL (1.7 kW EOL). These arrays had an area of ~ 29 sq. m and were articulated about one axis. Two 40 Ahr NiCd batteries provided power during eclipse. A hydrazine propulsion system with 24 4.45 N thrusters was used for orbit circularization and orbit maintenance. Spacecraft telemetry and commanding were performed via a Ku-band communications system, with emergency backup provided by an S-band system.
Payload included:
- Two Single Access (SA) antennas - each antenna was a 4.9 m diameter molybdenum wire mesh antenna that could be used for Ku-band and S-band links. Each antenna was steerable in 2-axes and communicates with one target spacecraft at a time.
- One Multiple Access (MA) S-band antenna array - an electronically steerable phased array consisting of 30 fixed helix antennas. The MA array could receive data from up to 20 user satellites simultaneously, although it could transmit to only one satellite at a time. Twelve of the helices could transmit and receive, with the remainder only able to receive.
- One Space to Ground Link antenna (SGL) - a 2 meter parabolic antenna operating at Ku-band that provided the communications link between the satellite and the ground. All customer data were sent through this dish, as were all regular TDRS command and telemetry signals. The antenna was gimbaled on two axes.
- One S-band omni antenna - a conical log spiral antenna used during the satellite's deployment phase and as a backup the event of a spacecraft emergency. This antenna did not support customer links.
- One small Ku-band and one small C-band antenna were also carried, designed to support communications with Westar satellites, but were no longer used.
- Transponders:
- Four (plus 2 spare) 25W Ku-band TWTAs for LP (linearly polarized) zone coverage.
- Two (plus 2 spare) 1.5W Ku-band TWTAs for CP (circularly polarized) spot coverage.
- Two (plus 4 spare) 25W Ku-band TWTAs for LP zone coverage.
- Two (plus 2 spare) 1.5W Ku-band TWTAs for CP spot coverage
- 12 5W TWTAs for LP C-Band up/downtown (plus 2 spare)
- 26W S-band SSPAs (used for intersatellite links)
- Eight (plus 4 spare) 3.5W S-band SSPAs (used for intersatellite links)
Hughes received a contract on 23 February 1995 for TDRS replacement - $ 481.6 million for 3 HS-601 spacecraft with added Ka band. Last launch was originally set for 2002. Program total cost to 1997 was $ 3.3 billion over 10 years.
Subtopics
STS-26 First shuttle reflight after Challenger disaster. Deployed TDRS 3.
STS-41-H Planned Department of Defense or TDRS deployment shuttle mission. Cancelled due to IUS failure.
STS-43 Deployed TDRS 5 satellite.
STS-51-DA Planned TDRS/IUS deployment shuttle mission. Cancelled due to IUS failure.
STS-51-E Planned TDRS/IUS deployment shuttle mission. Cancelled due to IUS failure.
STS-51-L First shuttle launch from pad LC-39B. An O-ring failure in a solid rocket booster led to leaking of hot gases against the external tank; exploded 73 seconds after launch, all seven crew, with no means of escape, were killed when crew cabin hit the ocean.
STS-6 First flight of space shuttle Challenger. First space walk of Shuttle program. Deployed Tracking and Data Relay Satellite.
STS-61-M Planned TDRS/IUS deployment shuttle mission. Cancelled after Challenger disaster.
TDRS American military communications satellite. Satellite communications network, for use by Shuttle and US military satellites. Communication satellite built by TRW for NASA, USA. Launched 1983 - 1993.
Family:
Communications,
Geosynchronous orbit,
Military communications sat.
Country:
USA.
Launch Vehicles:
Space Shuttle.
Projects:
STS.
Launch Sites:
Cape Canaveral,
Cape Canaveral LC39A,
Cape Canaveral LC39B.
Agency:
NASA,
Contel,
TRW.
Bibliography:
2,
279,
4150,
4151,
4152,
6,
6968.
Photo Gallery
TDRS 1 TDRS 1
Credit: Manufacturer Image
TDRS 7 TDRS 7
Credit: Manufacturer Image
STS-6 STS-6
Deployment of the TDRS by STS-6 Challenger
Credit: NASA
STS-6 STS-6
TDRS satellite over African Rift Valley, Kenya, Africa
Credit: NASA
STS-26 STS-26
STS-26 Discovery, Orbiter Vehicle (OV) 103, IUS / TDRS-C deployment
Credit: NASA
STS-26 STS-26
STS-26 Discovery, Orbiter Vehicle (OV) 103, IUS / TDRS-C deployment
Credit: NASA
STS-26 STS-26
STS-26 Discovery, Orbiter Vehicle (OV) 103, IUS / TDRS-C deployment
Credit: NASA
STS-26 STS-26
STS-26 Discovery, Orbiter Vehicle (OV) 103, IUS / TDRS-C deployment
Credit: NASA
STS-26 STS-26
STS-26 Discovery, Orbiter Vehicle (OV) 103, IUS / TDRS-C deployment
Credit: NASA
STS-29 STS-29
STS-29 IUS with TDRS-D drifts above Earth's surface during post deployment
Credit: NASA
STS-29 STS-29
STS-29 IUS with TDRS-D after deployment from Discovery, OV-103
Credit: NASA
1978 April 6 - .
LV Family:
Titan,
Shuttle.
Launch Vehicle:
Titan 34D,
Shuttle.
- Titan III 34D/IUS not to be used as backup for launch of a Tracking and Data Relay Satellite. - .
Spacecraft: TDRS.
NASA withdrew its requirement for a Titan III 34D/IUS to be used as backup for a space shuttle launch of a Tracking and Data Relay Satellite in 1980..
1983 April 4 - .
18:30 GMT - .
Launch Site:
Cape Canaveral.
Launch Complex:
Cape Canaveral LC39A.
Launch Platform: MLP2.
LV Family:
Shuttle.
Launch Vehicle:
Space Shuttle.
- TDRS 1 - .
Payload: TDRS A. Mass: 2,268 kg (5,000 lb). Nation: USA.
Agency: NASA Greenbelt.
Program: STS.
Class: Communications.
Type: Civilian communications satellite. Spacecraft: TDRS.
USAF Sat Cat: 13969 . COSPAR: 1983-026B. Apogee: 35,976 km (22,354 mi). Perigee: 35,835 km (22,266 mi). Inclination: 7.40 deg. Period: 1,442.20 min.
Element of satellite communications network, deployed from STS-6 5 April 1983. Spacecraft engaged in practical applications and uses of space technology such as weather or communication (US Cat C). Positioned in geosynchronous orbit at 67 deg W in 1983; 41 deg W in 1983-1989; 79 deg W in 1989-1990; 170 deg W in 1990-1993; 85 deg E in 1994-1995; 49 deg W in 1996-on. As of 5 September 2001 located at 49.36 deg W drifting at 0.010 deg E per day. As of 2007 Mar 9 located at 48.98W drifting at 0.029W degrees per day.
1986 January 28 - .
16:38 GMT - .
Launch Site:
Cape Canaveral.
Launch Complex:
Cape Canaveral LC39B.
Launch Platform: MLP2.
LV Family:
Shuttle.
Launch Vehicle:
Space Shuttle.
FAILURE: Failure.
- TDRS B - .
Payload: TDRS B. Mass: 2,240 kg (4,930 lb). Nation: USA.
Agency: NASA.
Program: STS.
Class: Communications.
Type: Civilian communications satellite. Spacecraft: TDRS.
Apogee: 15 km (9 mi).
1988 September 29 - .
15:37 GMT - .
Launch Site:
Cape Canaveral.
Launch Complex:
Cape Canaveral LC39B.
Launch Platform: MLP2.
LV Family:
Shuttle.
Launch Vehicle:
Space Shuttle.
1989 March 13 - .
14:57 GMT - .
Launch Site:
Cape Canaveral.
Launch Complex:
Cape Canaveral LC39B.
Launch Platform: MLP2.
LV Family:
Shuttle.
Launch Vehicle:
Space Shuttle.
1991 August 2 - .
15:02 GMT - .
Launch Site:
Cape Canaveral.
Launch Complex:
Cape Canaveral LC39A.
Launch Platform: MLP1.
LV Family:
Shuttle.
Launch Vehicle:
Space Shuttle.
1993 January 13 - .
13:59 GMT - .
Launch Site:
Cape Canaveral.
Launch Complex:
Cape Canaveral LC39B.
Launch Platform: MLP2.
LV Family:
Shuttle.
Launch Vehicle:
Space Shuttle.
1995 July 13 - .
13:41 GMT - .
Launch Site:
Cape Canaveral.
Launch Complex:
Cape Canaveral LC39B.
Launch Platform: MLP2.
LV Family:
Shuttle.
Launch Vehicle:
Space Shuttle.
