Engineers at Hughes Space and Communications conduct vibration testing on Galaxy 4R, a high-power Hughes 601HP built for PanAmSat Corporation. Photo: Hughes

Hughes Space and Communications Co., the world's largest satellite manufacturer, will launch Galaxy 4R on April 18 for PanAmSat Corp.

This is the fourth Hughes-built satellite to launch this year.

The high-power Hughes 601HP satellite was shipped March 27 to Europe's spaceport in South America. Engineers and technicians from satellite builder Hughes Space and Communications Co. ("HSC") and rocket builder Arianespace are making final preparations for the launch, set for 9:29 p.m. local time on April 18 (5:29 p.m. PDT, 0029 April 19 GMT), using an Ariane 42L vehicle.

Galaxy 4R will be the third satellite Hughes has launched for PanAmSat in 120 days, including the launch of Galaxy 11, the first Hughes 702 satellite, on Dec. 21, 1999, and Galaxy 10R, a Hughes 601HP that was launched on Jan. 24.

"Galaxy 4R is the seventh consecutive satellite that HSC has delivered on time to meet our customers' requirements," said Tig H. Krekel, president and chief executive officer of HSC.

"This clearly demonstrates our commitment to our customers, a commitment that has been re-energized during the last 12 months. HSC is firmly committed to delivering high-quality satellites on-schedule. This is the reason for our existence, and it keeps important customers like PanAmSat returning."

Galaxy 4R carries 48 active transponders, 24 in C-band and 24 in Ku-band, and weighs 3,668 kilograms (8,088 pounds) at launch. The geostationary satellite will be placed 36,000 kilometers (22,300 miles) above the equator at 99 degrees West longitude.

The 8,800-watt satellite features leading technologies from Hughes Electronics subsidiaries, including Hughes Electron Dynamics' xenon ion propulsion system, XIPS, which is 10 times more efficient than its chemical counterpart, and Spectrolab's dual-junction solar cells with conversion efficiencies of more than 21 percent.

HSC is the world's leading manufacturer of commercial communications satellites, having built nearly 40 percent of those in operation. It also is a major supplier of spacecraft and equipment to the U.S. government, and a builder of weather satellites for the United States and Japan.

PanAmSat Corp., based in Greenwich, Conn., is a leading provider of global video and data broadcasting services via satellite. The company builds, owns and operates networks that deliver entertainment and information to cable television systems, TV broadcast affiliates, direct-to-home TV operators, Internet service providers, telecommunications companies and corporations.

With 20 spacecraft in orbit today, PanAmSat has the world's largest commercial geostationary satellite network. The company will expand its global fleet to 24 spacecraft by mid-2001.

HSC is a unit of Hughes Electronics Corp., the world's leading provider of digital television entertainment, satellite services, and satellite-based private business networks. PanAmSat is 81 percent owned by Hughes Electronics. The earnings of Hughes Electronics, a unit of General Motors Corp., are used to calculate the earnings per share attributable to the General Motors Class H common stock.