The Boeing 376 (sometimes referred to as the BSS-376, and previously as the HS-376) is a communications satellite bus introduced in 1978 by Hughes Space and Communications Company. It was a spin-stabilized bus, a successor to Hughes HS-333.
Design The satellite bus was designed and manufactured by Hughes. This spin-stabilized platform had two main sections. The spinning section was kept rotating at 50 rpm to maintain attitude, and a despun section was used by the payload to maintain radio coverage.
The spinning section included the apogee kick motor, most of the attitude control, the power subsystem and the command and telemetry subsystems. The despun section contained the communications payload, including the antennas and transponders.
The stock version had a launch mass of , a mass of after reaching geostationary orbit and an 8 to 10-year design life. When stowed for launch, its dimensions were in height and in diameter. With its solar panels fully extended its height was .
Its power system generated approximately 1,100 to 1,200 watts of power at beginning of life, thanks to two cylindrical solar panels. The bottom panel was retracted around the body and top panel for launch, and extended downwards for operation. It also had two NiCd batteries for solar eclipses.
Versions There were four variations of this platform: HS-376: The original version of the platform was launched in 1977. It had a mass between . HS-376L: The Longer life version of the platform was launched in 1991. It had reduced power of 700 Watts and reduced electronics weight, which allowed for increased station keeping propellant supply. This lengthened the design life to 13.5 years. HS-376HP: A Higher Power version of the platform was launched in 1995. It had a mass between . HS-376W: The Wide version of the platform was launched in 1990. It was wider, more powerful and modernized electronics. It was a joint development with INPE. It had a diameter of and more power.
Satellites The HS-376 was a very successful satellite platform with 58 satellites ordered, built and launched. It was also the first satellite to launch from the Space Shuttle.
Satellite Other names Operator Model Ordered Launch Launch vehicle Launch result Mass (kg) at... Remarks Launch BOL SBS 1 HS-376 1977 1980-11-15 Delta-3910/PAM-D 1117 540 SBS 2 HS-376 1977 1981-09-24 Delta-3910/PAM-D 1117 540 Westar 4 HS-376 1980 1982-02-26 Delta-3910/PAM-D 1100 582 Westar 5 HS-376 1982 1982-06-09 Delta-3910/PAM-D 1100 582 Anik D1 HS-376 1982-08-26 Delta-3920/PAM-D 1140 634 Anik C3 HS-376 1978 1982-11-11 Shuttle/PAM-D 1140 563 SBS 3 HS-376 1981 1982-11-11 Shuttle/PAM-D 1117 540 Anik C2 Nahuel I2 HS-376 1978 1983-06-18 Shuttle/PAM-D 1140 563 Palapa B1 Palapa Pacific 1 HS-376 1980 1983-06-18 Shuttle/PAM-D 1200 692 Galaxy 1 HS-376 1983-06-28 Delta-3920/PAM-D 1200 709 Telstar 301 Arabsat-1E HS-376 1980 1983-07-28 Delta-3920/PAM-D 1140 653 Galaxy 2 HS-376 1983-09-22 Delta-3920/PAM-D 1200 709 Palapa B2 HS-376 1980 1984-02-03 Shuttle/PAM-D 1200 692 Launched along Westar 6. PAM-D failed to ignite, Shuttle recovered the satellite. Was relaunched as Palapa B2R. Westar 6 HS-376 1984-02-03 Shuttle/PAM-D 1244 582 Launched along Palapa B2. PAM-D failed to ignite, Shuttle recovered the satellite. Was relaunched as AsiaSat 1. SBS 4 HGS 5 HS-376 1983 1984-08-30 Shuttle/PAM-D 1117 540 Telstar 302 HS-376 1980 1984-08-30 Shuttle/PAM-D 1140 653 Galaxy 3 HS-376 1984-09-21 Delta-3920/PAM-D 1200 709 Anik D2 Satcom 4RArabsat 1D HS-376 1984-11-08 Shuttle/PAM-D 1140 634 Brasilsat-A1 SBTS 1 HS-376 1982 1985-02-08 Ariane 3 1195 Anik C1 Nahuel I1Brasil 1T HS-376 1978 1985-04-12 Shuttle/PAM-D 1140 563 Morelos 1 HS-376 1982 1985-06-17 Shuttle/PAM-D 1140 647 Telstar 303 HS-376 1980 1985-06-17 Shuttle/PAM-D 1140 653 Aussat A1 Optus A1 HS-376 1982 1985-08-27 Shuttle/PAM-D 1250 654 Aussat A2 Optus A2 HS-376 1982 1985-11-27 Shuttle/PAM-D 1250 654 Morelos 2 HS-376 1982 1985-11-27 Shuttle/PAM-D 1140 647 Brasilsat-A2 SBTS 2 HS-376 1982 1986-03-28 Ariane 3 1195 Palapa B2P Palapa B3Agila 1 HS-376 1984 1987-03-20 Delta-3920/PAM-D 1200 692 Aussat A3 Optus A3 HS-376 1982 1987-09-16 Ariane 3 1250 696 SBS 5 HS-376 1983 1988-09-08 Ariane 3 1117 540 Marcopolo 1 Sirius 1Sirius W HS-376 1987 1989-08-27 Delta-4925 1250 660 AsiaSat 1 HS-376 1990-04-07 Long March 3 1244 582 Was Westar 6, but the launch on Space Shuttle failed. It was recovered and launched again as AsiaSat 1. Palapa B2R NewSat 1 HS-376 1990-04-13 Delta-6925-8 1200 692 Was Palapa B2, but the launch on Space Shuttle failed. It was recovered and launched again as Palapa B2R. Marcopolo 2 Thor 1 HS-376 1987 1990-08-18 Delta-6925-8 1250 662 Prowler HS-376 1990-11-15 Shuttle/PAM-D Galaxy 5 HS-376 1989 1992-03-14 Atlas I 1390 788 Palapa B4 HS-376 1992-05-14 Delta-7925-8 1200 692 Galaxy 1R HS-376 1989 1992-08-22 Atlas I 1390 788 Launch failure Galaxy 6 Westar 6S HS-376 1983 1992-10-12 Ariane-44L 1390 709 Thaicom 1 Thaicom 1A HS-376L 1991 1993-12-18 Ariane-44L 1080 629 Galaxy 1R2 HS-376 1992 1994-02-19 Delta-7925-8 1390 788 APSTAR-1 ZX-5E HS-376 1992 1994-07-21 Long March 3 1400 726 Brasilsat B1 HS-376W 1990 1994-08-10 Ariane-44LP 1757 1052 Thaicom 2 HS-376L 1991 1994-10-07 Ariane-44L 1080 629 Brasilsat B2 HS-376W 1990 1995-03-28 Ariane-44LP 1757 1052 MEASAT-1 AFRICASAT-1 HS-376 1994 1996-01-12 Ariane-44L 1450 886 Galaxy 9 HS-376 1995 1996-05-24 Delta-7925 1390 788 APSTAR-1A ZX-5D HS-376 1995 1996-07-03 Long March 3 1400 726 ZX 7 Chinasat-7HGS 2 HS-376 1995 1996-08-18 Long March 3 1384 734 Launch failure MEASAT-2 AFRICASAT-2 HS-376 1994 1996-11-13 Ariane-44L 1450 886 BSAT-1a HS-376 1993 1997-04-16 Ariane-44LP 1236 723 Thor 2 HS-376HP 1995 1997-05-20 Delta-7925 1467 853 Brasilsat B3 HS-376W 1995 1998-02-04 Ariane-44LP 1757 1052 BSAT-1b HS-376 1993 1998-04-28 Ariane-44P 1236 723 Thor 3 HS-376HP 1997 1998-06-10 Delta-7925 1451 853 Sirius 3 HS-376HP 1997 1998-10-05 Ariane-44L 1465 815 Bonum 1 HS-376HP 1997 1998-11-22 Delta-7925 1425 793 Brasilsat B4 HS-376W 1998 2000-08-17 Ariane-44LP 1757 1052 Astra 2D HS-376HP 1999 2000-12-20 Ariane 5G 1445 824 Astra 3A HS-376HP 2000 2002-03-29 Ariane-44L 1514 908 eBird 1 Eurobird 3Eutelsat 33AEutelsat 31A HS-376HP 2000 2003-09-27 Ariane 5G 1530 895
See also
Boeing 601 Boeing Satellite Development Center
References