| Manufacturer | Boeing Satellite Development Center | ||
|---|---|---|---|
| Country of origin | United States | ||
| Applications | Communications satellite | ||
| Specifications | |||
| Spacecraft type | Spin-stabilized | ||
| Design life | 8 years | ||
| Launch mass | 2.2 to 2.5 t (2.4 to 2.8 tons) | ||
| Dimensions | Diameter: 3.7 m (12 ft) Height (stowed): 3.4 m (11 ft) Height (deployed): 10 m (33 ft) | ||
| Power | 2 to 2.2 kWatts | ||
| Batteries | 2 × 38Ah NiH2 batteries | ||
| Regime | Geostationary orbit | ||
| Production | |||
| Status | Retired | ||
| Built | 3 | ||
| On order | 3 | ||
| Launched | 3 | ||
| Retired | 3 | ||
| Maiden launch | JCSAT-1 March 6, 1989 | ||
| Last launch | SBS 6, October 12, 1990 | ||
| Related spacecraft | |||
| Derived from | HS-376 | ||
| |||
The Hughes 393 (sometimes referred to as the HS-393) is a communications satellite bus introduced in 1985 by Hughes Space and Communications Company. It was a spin-stabilized bus that had twice as much power as the HS-376 platform. [1] [2]
The satellite bus was designed and manufactured by Hughes. It had a launch mass of 2.2 to 2.5 t (2.4 to 2.8 tons), a mass of 1.35 to 1.5 t (1.49 to 1.65 tons) after reaching geostationary orbit, and an 8-year design life. When stowed for launch, its dimensions were 3.4 m (11 ft) in height and 3.7 m (12 ft) in diameter. [1] [3] With its solar panels fully extended its height was 10 m (33 ft). [4] [5]
Its power system generated approximately 2,350 watts of power at beginning of life and 2,200 at end of life, thanks to two cylindrical solar panels. These panels used K7 and K4-3/4 solar cells, with more than twice the number of cells than on the HS-376. [1] The bottom panel was retracted around the body and top panel for launch, and extended downwards for operation. [1] It also had two 38 Ah NiH2 batteries. [4]
Its propulsion system was composed of two R-4D liquid apogee engines with a thrust of 490 N (110 lbf). It also had two axial and four radial 22 N (4.9 lbf) bipropellant thrusters for station-keeping and attitude control. [1] It included enough propellant for orbit circularization and 8 years of operation. [4]
Its payload was composed of a 2.4 m (7 ft 10 in) antenna that fed Ku band transponders. [1] [3]
The HS-393 was a more powerful platform than the HS-376, being able to supply 2,200 kW of power versus the 1,400 kW of the HS-376HP. Only three were ever built. [2]
| Satellite | Other Names | Operator | Model | Ordered | Launch | Launch Vehicle | Launch Result | Mass at launch (kg) | Mass at BOL (kg) | Remarks |
|---|---|---|---|---|---|---|---|---|---|---|
| JCSAT-1 | JSAT Corporation | HS-393 | 1985 | 1989-03-06 | Ariane 44LP | Success | 2,280 kg (5,030 lb) | 1,346 kg (2,967 lb) | First Japanese commercial satellite. [4] [1] | |
| JCSAT-2 | JSAT Corporation | HS-393 | 1985 | 1990-01-01 | Commercial Titan III | Success | 2,280 kg (5,030 lb) | 1,346 kg (2,967 lb) | [4] [1] | |
| SBS 6 | Satellite Business Systems | HS-393 | 1985 | 1990-10-12 | Ariane 44L | Success | 2,478 kg (5,463 lb) | 1,500 kg (3,300 lb) | Launched alongside Galaxy 6. [5] [3] | |
SBS 4 was a geostationary communications satellite designed and manufactured by Hughes on the HS-376 platform. It was ordered by Satellite Business Systems, which later sold it to Hughes Communications. It had a Ku band payload and operated at 94°W longitude.
JCSAT-5A or N-STAR d, known as JCSAT-9 before launch, is a geostationary communications satellite operated by SKY Perfect JSAT Group (JSAT) which was designed and manufactured by Lockheed Martin on the A2100 platform.
JSAT Corporation (JSAT) was the first private Japanese satellite operator, which owned the JSAT satellites, as well as operated and partially owned the N-Star with NTT DoCoMo. Its origins can be traced to the funding of Japan Communications Satellite Company (JCSAT) and Satellite Japan Corporation in 1985. Both companies merged into Japan Satellite Systems Inc. in 1993. In 2000 the company was renamed as JSAT Corporation and was listed in the First Section of the Tokyo Stock Exchange. In September 1, 2008, the company was merged into the SKY Perfect JSAT Group.
JCSAT-11, was a geostationary communications satellite ordered by JSAT Corporation which was designed and manufactured by Lockheed Martin on the A2100 platform. The satellite was designated to be used as an on-orbit, but was lost on launch failure.
N-SAT-110, also known as JCSAT-7, JCSAT-110, Superbird-5 and Superbird-D, is a Japanese geostationary communications satellite which was operated by JSAT Corporation and Space Communications Corporation until both companies merged into SKY Perfect JSAT Group in 2008. It is positioned in geostationary orbit at a longitude of 110° East, from where it is used to provide communications services to Japan.
BSAT-1a was a geostationary communications satellite designed and manufactured by Hughes on the HS-376 platform. It was originally ordered and operated by the Broadcasting Satellite System Corporation (B-SAT). It was used as the main satellite to broadcast television channels for NHK and WOWOW over Japan. It had a pure Ku band payload and operated on the 110°E longitude until it was replaced, along its backup BSAT-1b, by BSAT-3a. On 3 August 2010, it was decommissioned and placed on a graveyard orbit.
BSAT-1b was a geostationary communications satellite designed and manufactured by Hughes on the HS-376 platform. It was originally ordered and operated by the Broadcasting Satellite System Corporation (B-SAT). It was used as backup of BSAT-1a to broadcast television channels for NHK and WOWOW over Japan. It had a pure Ku band payload and operated on the 110°E longitude until it was replaced, along its twin BSAT-1a, by BSAT-3a.
Superbird-A2, known as Superbird-6 before launch, was a geostationary communications satellite ordered and operated by Space Communications Corporation (SCC) that was designed and manufactured by Hughes on the HS-601 platform. It had a mixed Ku band and Ka band payload and was expected replace Superbird-A at the position at 158°East longitude. It was expected to provided television signals and business communications services throughout Japan, southern and eastern Asia, and Hawaii.
The JSAT constellation is a communication and broadcasting satellite constellation formerly operated by JSAT Corporation and currently by SKY Perfect JSAT Group. It has become the most important commercial constellation in Japan, and fifth in the world. It has practically amalgamated all private satellite operators in Japan, with only B-SAT left as a local competitor.
JCSAT-3A, known as JCSAT-10 before launch, is a geostationary communications satellite operated by SKY Perfect JSAT Group (JSAT) which was designed and manufactured by Lockheed Martin on the A2100 platform.
JCSAT-2A, known as JCSAT-8 before launch, is a geostationary communications satellite operated by SKY Perfect JSAT Group (JSAT) which was designed and manufactured by Boeing on the BSS-601 platform. It has Ku band and C band payload and was used to replace JCSAT-2 at the 154°East longitude. It covers Japan, East Asia, Australia and Hawaii.
JCSAT-1B, known as JCSAT-5 before launch, is a geostationary communications satellite operated by SKY Perfect JSAT Group (JSAT) which was designed and manufactured by Hughes on the HS-601 platform. It has a pure Ku band payload and was used to replace JCSAT-1 at the 150°East longitude. It covers Japan, Korea, most of China, Thailand, Vietnam, Laos, part of Indonesia, part of Malaysia and Hawaii.
Intelsat 26 was known as JCSAT-5 before launch and as JCSAT-R until it was sold to Intelsat in 2009. It is a geostationary communications satellite designed and manufactured by Hughes on the HS-601 platform. It was originally ordered by JSAT Corporation, which later merged into the SKY Perfect JSAT Group. It has a mixed Ku band and C band payload and was used as an on orbit spare.
JCSAT-3 was a geostationary communications satellite designed and manufactured by Hughes on the HS-601 platform. It was originally ordered by JSAT Corporation, which later merged into the SKY Perfect JSAT Group. It has a mixed Ku band and C band payload and operated on the 128°E longitude until it was replaced by JCSAT-3A.
JCSAT-1 was a geostationary communications satellite designed and manufactured by Hughes on the HS-393 platform. It was originally ordered by Japan Communications Satellite Company (JCSAT), which later merged into the JSAT Corporation. It had a Ku band payload and operated on the 150°E longitude until it was replaced by JCSAT-1B.
JCSAT-2 was a geostationary communications satellite designed and manufactured by Hughes on the HS-393 platform. It was originally ordered by Japan Communications Satellite Company (JCSAT), which later merged into the JSAT Corporation. It had a Ku band payload and operated on the 154°E longitude until it was replaced by JCSAT-2A.
The Boeing 376 is a communications satellite bus introduced in 1978 by Hughes Space and Communications Company. It was a spin-stabilized bus that the manufacturer claims was the first standardized platform.
SBS 2 was a geostationary communications satellite designed and manufactured by Hughes on the HS-376 platform. It was ordered by Satellite Business Systems, which later sold it to Hughes Communications. It had a Ku band payload and operated on the 117°W longitude.
SBS 6 was a geostationary communications satellite designed and manufactured by Hughes on the HS-393 platform. It was originally ordered by Satellite Business Systems, which later sold it to Hughes Communications and was last used by Intelsat. It had a Ku band payload and operated on the 95°W longitude.
Superbird-C, also known as Superbird-3 or Superbird-A3, was a geostationary communications satellite ordered and operated by Space Communications Corporation (SCC) that was designed and manufactured by Hughes on the HS-601 platform. It has a pure Ku band payload and was used fill the position at 144°East longitude. It provided television signals and business communications services throughout Japan, southern and eastern Asia, and Hawaii.
