proton-m_000911 A new sibling is being prepared to join the family of Proton boosters -- the workhorses of the Russian space program.
The more powerful and advanced launcher, called Proton M, is currently being prepared in
Baikonur Cosmodrome in Kazakhstan for its inaugural flight within next two months. From head to toe, the Proton M sports additions and improvements, which promise to advance its stakes in a competitive marketplace of commercial satellite launches.
The Proton K (left) and Proton M launch vehicles
For the first time, a digital flight-control system will replace the traditional analog hardware aboard Proton. It will allow more efficient propellant consumption during the flight and, as a result, the delivery of bigger payloads into the orbit.
The rocket will become even more powerful thanks to a new version of the first-stage's RD-253 engines. Moscow's Energomash development center increased the engine thrust from 151 to 160 tons.
These two improvements will punch up the Proton M, allowing it to lift 22 tons of cargo into low Earth orbit, compared to 20.7 tons for the standard Proton booster.
A new upper stage
For missions beyond initial low orbits, the new Proton will be fitted with a more advanced fourth stage called Breeze M. The new stage already completed its inaugural flight on a Proton K booster in May when it
delivered the Gorizont communications satellite. Breeze M takes much less space on the launch vehicle compared to its predecessors leaving additional volume for the cargo. As a result, the new payload shroud topping the rocket will offer 2.5 times more volume for the satellites riding Proton M.
Test flight plan
According to the representatives of the Russian Aviation and Space Agency, the inaugural launch of the Proton M is scheduled for October 28. The mission, however, could be pushed to the beginning of November by an extremely tight flight manifest for Proton K boosters stretching through the end of year.
The next Proton K launch is scheduled for September 27, 2000, when the rocket will loft a trio of GLONASS navigation satellites for the Russian Ministry of Defense. Also, two Proton commercial launches carrying GE-1A and GE-6 communications satellites are scheduled for October 8 and October 22.
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Currently, only one of three active launch pads for the Proton booster in Baikonur has been modified to accommodate the Proton M-Breeze M stack.
The last Ekran to go up
The Proton M test flight will also mark the end of an era for a generation of the
Russian communications satellites. During its test mission the rocket will deliver Ekran M24, a communications satellite, into circular orbit 22,370 miles (36,000 kilometers) above the equator.
This 2-ton spacecraft was developed in the 1970s and it will be the last of its kind to be launched. The capacity of its single TV-relay channel is dwarfed by modern communications satellites equipped with dozens of transmitters.
The Proton M in a new spacecraft hardware assembly building in Baikonur
The Breeze M upper stage will place Ekran M24 at a point 99 degrees east longitude, where it will provide direct television broadcasts for eastern regions of Russia. Once in this position the new satellite will replace its ailing sibling Ekran M18.
Representatives of the Russian Aviation and Space Agency said that one Ekran M-type spacecraft will remain on the ground after the Proton M test launch. However, this satellite will likely end up in a museum, since its storage time has already expired and there are no plans to launch it.
Things to come
Khrunichev Enterprise in Moscow, the company that developed the Proton, hopes to introduce even more dramatic changes in their powerhouse booster. Currently, KB Salyut -- Khrunichev's design arm -- is developing an even more powerful upper stage for the Proton M. Designated KVRB, it will employ supercold liquid hydrogen and liquid oxygen -- the same propellant used in the
U.S. Space Shuttle's main engines.The development of the cryogenic stage, initiated by Khrunichev in 1980s, had been stalled for years by Russia's financial problems. The work, however, has recently moved forward, spurred in part due to commercial deals with India, which has eyed similar technology for its own space-launch system.
KB Salyut has developed a cryogenic upper stage for the Indian government and hopes to use its off-the-shelf technology for the even bigger stage for Proton. KB Salyut representatives said that the Proton's cryogenic stage would hold 18 tons of propellant, compared to 12 tons carried by the stage developed for the Indian government.
With the new cryogenic stage, the enhanced Proton rocket will be able to compete with the
Ariane 5 rocket, the most advanced European launcher, despite the geographical disadvantage plaguing Russian launches from higher-latitude Kazakhstan compared to Ariane's launch site near the equator in French Guinea. Equatorial launches get an added boost due to Earth's rotation.
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