Commercial launch services are used to place satellites in their respective orbits. Launch services represent, by far, the most lucrative aspect of the launch-for-hire business. The European Space Agency (ESA), United States, Russia, People's Republic of China, India, and some international organizations supply or plan to supply launch vehicles for the purpose of placing satellites in orbit. Although the majority of launch vehicles are used for broadcast satellites, satellites are also launched for wireless telephony. For example, the mobile communications systems Globalstar and Iridium Satellite LLC are cell phone satellite networks for global use.
By 2000 the ESA's Arianespace Consortium had 125 launchings of orbit communications satellites (comsats). The basic first stage of a launch vehicle has four liquid propellant engines, but the Ariane launch vehicle has great versatility because of the number of engines that can be attached to its first stage. Two solid or two liquid propellant or two solid and two liquid propellant or four liquid propellant engines can be added to the first stage. This permits a wide variety of payloads to be placed in orbit. Arianespace also operates a heavy-lift rocket, the Ariane 5, which is intended mostly for commercial use but can be used for other purposes: the launching of scientific and military spacecraft, for example.
In the United States two companies dominate the launching business, Lockheed Martin (LM) and Boeing. LM supplies the various configurations of the Atlas/Centaur launch vehicle, and Boeing offers the Delta class of launch vehicles, including Delta II, Delta III, and Delta IV. The mass of payload that each Delta can lift into orbit distinguishes them from other launch vehicles. The Delta vehicles can have various additional solid propellant engines attached to their first stage, allowing still further variations in payload-lifting capability. For example, three or six or nine solids may be attached to the first stage of the Delta II.
LM's Atlas/Centaur can have variations in the type of first stage engines used or the size of first stage propellant tanks. LM has a business arrangement with the Khrunichev and Energia companies of Russia for the manufacture and use of a rocket engine developed by Russia that will be used in the first stage of the Atlas. It will be a replacement for the less powerful engines that have been used in the past.
In conjunction with Russian companies, LM uses the Russian four-stage Proton launch vehicle to launch payloads mostly to geosynchronous orbit . Proton has also been used to launch Iridium satellites, seven at a time, into a 800-kilometer (480-mile) orbit.
The Russians use their Proton launch vehicle for their own launches as well. In addition, a French-Russian company called Starsem uses the Russian Soyuz to launch commercial payloads. Soyuz is a modification, largely in its upper (third) stage, of the launch vehicle used to send cosmonauts to the Mir space station.
Eurokot, a German-Russian organization, uses modified Russian intercontinental ballistic missiles, known in the Western world (i.e., the North Atlantic Treaty Organization [NATO]) as the SS-19, Stiletto, to place payloads in low Earth orbit . All stages of these are made of solid propellants. They are launched from silos buried deep in the ground (like the U.S. Minuteman missiles). They have seen very limited use for payloads of about two tons, which means they are restricted to launching wireless telephony satellites and other small payloads.
Russia is developing a new series of rockets called Angara, which are intended to replace many of Russia's present stable of launch vehicles both for commercial and private use. The payload capability can range across the entire spectrum of currently available Russian rocketry and extend beyond to larger payloads.
The People's Republic of China has developed a series of rockets, all called Long March. The rockets range from a two-stage Long March 2C used to launch a pair of Iridium satellites to the three-stage Long March 3B used for launching comsats to geosynchronous orbit. China's ability to launch comsats, most of which are manufactured in the United States, has been hampered by political differences between the two countries. During the period 1998 to early 2000 very few U.S.-built satellites were exported to China for launching because of changes in U.S. export controls for space hardware.
Other International Organizations
A number of other launch vehicles are available which have seen limited use in very specific areas. The Pegasus and Taurus, built by the Orbital Sciences Corporation of the United States, have launched small payloads of 400 kilograms (880 pounds), among which have been clusters of seven small comsats used for the transmittal of data for business.
The country of Ukraine together with a division of Boeing, the Russian Energia Company, and the Norwegian company Kvaerner Maritime (a ship and oil rig builder) have formed Sea Launch. Sea Launch consists of a command ship, a former oil rig converted to a seagoing launching platform, a two-stage rocket called Zenit, and a third stage for the Zenit. The platform and the ship are based at Long Beach, California, and travel to longitude 154 degrees west on the equator for launching. This procedure takes advantage of Earth's rotation speed, thus adding 1,524 feet/second at the equator for the Zenit 3SL, either reducing the amount of propellant needed or permitting an increase in payload weight. Sea Launch has successfully flown a simulated payload and has launched five commercial communications satellites.
The only reusable rocket to date is the U.S. space shuttle. The system that launches it is only partially reusable because the large tank holding liquid propellant is discarded after each launching and the solid rockets that are recovered from the ocean need extensive refurbishment at considerable expense before their reuse. Reusability is a much desired but not a realized concept. There have been paper studies, but nothing has been fully tested, leaving the commercial worth of reusable launch vehicles still in question.
see also Launch Facilities (volume 4); Launch Industry (volume 1); Launch Sites (volume 3); Launch Vehicles, Expendable (volume 1); Launch Vehicles, Reusable (volume 1); Reusable Launch Vehicles (volume 4); Rockets (volume 3); Spaceports (volume 1).
Saunders B. Kramer
Lockheed Martin. <http://www.lockheedmartin.com>.