Various ways of putting satellite in orbit<\/p>\n
JAKARTA (JP): Human-made satellites are usually lofted into
\nspace by expendable launch vehicles, or boosters. The vehicle or
\nlauncher is a rocket-powered vehicle launched from the Earth's
\nsurface or from an aircraft that can boost a satellite through
\nthe Earth's atmosphere and place it into orbit above the Earth or
\nother planetary bodies. A launch vehicle typically has more than
\none stage of propulsive devices.<\/p>\n
After ignition, a rocket lifts the launch vehicle and its
\nsatellite payload off the launch pad, imparting sufficient energy
\nto overcome the effects of gravity. A second stage firing places
\nthe payload into a low altitude circular, or parking orbit.<\/p>\n
Another rocket stage later sends the vehicle into an
\nelliptical transfer orbit intended to deliver it to
\ngeosynchronous altitude.<\/p>\n
More than 300 satellites are expected to be launched in the
\nnext four years.<\/p>\n
The world's major launch vehicle manufacturers include
\nArianespace, a European consortium based in France, Lockheed
\nMartin and McDonnell Douglas of the United States.<\/p>\n
Arianespace is the manufacturer of the Ariane rocket family,
\nwhich has entered its advanced generation, Ariane 5. Lockheed
\nMartin is well-known for its Atlas rocket, which is also using a
\nmore advanced Atlas IIAR. McDonnell Douglas is the builder of
\nDelta rocket.<\/p>\n
Meanwhile, the China Great Wall Industries Corp. has entered
\nthe international rocket rivalry with its Long March rocket
\nseries. The other player in the race includes the Russian
\nKrunichev (teamed with Lockheed) with its Proton rocket. On a
\nsmaller scale, there is the NPO Yuzhnoye of Ukraine with its
\nZenit rocket and Brazil with its VLS rocket.<\/p>\n
Arianespace's new lifter, the Ariane 5, is scheduled make its
\nmaiden demonstration flight next month. The new rocket, which
\nwill first begin its commercial mission late this year, is
\ndesigned to be more powerful and less complicated than the Ariane
\n4. The Ariane 5 will have just one main engine instead of four as
\nwith the Ariane 4. The advanced rocket will be able to carry
\nnearly seven tons of payload, up from 4.5 tons. As a result, the
\nAriane 5 will be able to carry two satellites of nearly three
\ntons, the weight for a common communications spacecraft.<\/p>\n
Two satellites owned by Indonesia are scheduled to be launched
\nby Ariane rockets. The Palapa-C2 is scheduled to be put on an
\nAriane 4 in May, while the Indostar-I will be launched by Ariane
\n5 next year.<\/p>\n
At present, Lockheed Martin is also developing the Atlas IIAR,
\ndue to enter service in 1998. The new space launch vehicle will
\noffer greater thrust than the current Atlas family -- the Atlas
\nI, Atlas II, Atlas IIA and Atlas IIAS. The Atlas IIAS, the fourth
\ngeneration and the most powerful in the Atlas family, was the
\nlauncher of Palapa-C1 in January 1996.<\/p>\n
To face the more competitive launch market, McDonnell is
\ndeveloping the Delta 3, a new generation of the Delta boosters.
\nFive of Indonesia's first and second satellite generations were
\nlofted by Delta rockets.<\/p>\n
In addition to advanced rockets, price is the strategy of the
\nsatellite launch players.<\/p>\n
Sources said that a launch by the Ariane 4 rocket usually
\ncosts about US$100 million, depending on the number of satellites
\nto be lifted off. An Ariane is able to carry two satellites per
\nlaunch.<\/p>\n
A launch by the Atlas rocket, which can only accommodate one
\nsatellite, usually costs $70 million.<\/p>\n
China, meanwhile, has reportedly tried to undercut rivals by
\noffering launches using Long March rockets for less than $45
\nmillion.<\/p>\n
Michael R. Wash, president of International Launch Service, an
\naffiliated firm of Lockheed Martin, admitted that launching costs
\nwere one of the most important things in grabbing customers.<\/p>\n
Another major aspect for maintaining reputation and in winning
\nthe satellite launching market is the rate of successful lift-
\noffs, as there is always a risk in any launch schedule.<\/p>\n
A failure, especially marked with an explosion, will usually
\ndisrupt the following launching schedules. Such a failure will
\nalso halt users from using a destroyed satellite's transponders.<\/p>\n
China Great Wall this year saw a launching failure at its
\nXichang launch site. A Long March 3B rocket, the newest of
\nChina's rockets which was on its maiden flight, exploded in a
\nball of fire and fell to Earth just 20 seconds after lift-off.<\/p>\n
The incident destroyed the Intelsat 708, a three-ton satellite
\nbelonging to the International Telecommunications Satellite
\nOrganization (Intelsat), the Washington-based global
\ntelecommunications consortium. The satellite was worth about $200
\nmillion.<\/p>\n
The accident on the 426-ton Long March 3B last month was the
\nsecond in just over a year. It was China's fourth space accident
\nwithin the last three years. In January last year, a U.S.-made
\nsatellite exploded 50 seconds after blast-off from the site.<\/p>\n
The incident this year has caused cancellation to any other
\nsatellite launch scheduled to use the Long March 3B in 1996.<\/p>\n
Recently, the Columbia space shuttle also failed to place an
\nItalian satellite into orbit due to a botched tether. The $100
\nmillion Italian satellite was gone because of the incident.<\/p>\n
One of Indonesia's satellites, Palapa-B2, was also lost in
\nJanuary 1984 shortly after being released from the Columbia.
\nFortunately, the spacecraft was found and brought back to the
\nearth in November that year.<\/p>\n
Meanwhile, an Ariane 44LP rocket failed to launch two
\nsatellites, Turksat1A and Eutelsat-2, in January 1994, causing a
\nloss of about $356 million. In December that year, the Ariane 42P
\nalso malfunctioned and failed to launch PAS-3, a $150 million
\nsatellite owned by Panamsat of the United States.<\/p>\n
The failures, all seven since Arianespace commenced its
\nprogram in 1979, caused a rescheduling for the Palapa-C1
\nlaunching late last year. Indonesia, determined to have the
\nPalapa-C1 in orbit on schedule, was then able to switch the
\nsatellite's launching to Lockheed Martin.<\/p>\n
In the meantime, Lockheed Martin's Atlas rocket has had 21
\nsuccessful launchings from July 19, 1993 to Jan. 31, 1996, when
\nthe country's Palapa-C1 was launched by Atlas IIAS. (icn)<\/p>",
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