Russia's space booster, the Soyuz, is receiving new engines and avionics.
Tim Furniss/LONDON
RUSSIA'S CENTRAL Specialised Design Bureau in Samara has formed a partnership with France's Aerospatiale and the European launcher organisation Arianespace to attempt to market the Russian Soyuz booster for launches into low-Earth orbit (LEO). Although the current market has not yet matured to make it viable commercially for new entrants, the potential for LEO systems for mobile communications and remote-sensing spacecraft is growing.
The Teal Group reported in a recent market analysis that "-the future of communications satellites lies in smaller, cheaper LEOs", to such an extent that the number of geostationary-orbit (GEO) satellites to be launched will probably decline from a maximum of 30 after 1998.
The link comes as the Samara bureau is finalising its planned facelift of the booster, the first version of which was flown in 1963. The world's most successful launcher, it has a first-stage powerplant which launched the former Soviet Union's first intercontinental ballistic missile in 1957 and Yuri Gagarin, the first man in space, in 1961. The new version will be called the Soyuz 2.
The Soyuz's maximum potential LEO lifting capability could increase by 750kg, to 8,250kg, launching eastwards from the Plesetsk Cosmodrome with new first-stage core and strap-on engines, a new second stage and modern avionics. Soyuz launches from the Baikonur Cosmodrome, leased from Kazakhstan, have attained an acknowledged maximum capability of 7,320kg.
Georgy Fomin, deputy designer general at Samara, says that the Soyuz 2 will be equipped with higher output engines and "-will be superior to its obsolete predecessors, the Vostok, Soyuz and Molniya".
It had been planned to introduce a versatile family of three uprated boosters, called the Rus, to the market. The improvements will now be limited to one vehicle and called the Soyuz 2, which will consist of a "standardised uprated package", with an available, additional Fregat upper stage for higher orbits, says Samara. The current Soyuz vehicles are the U and U2. The Soyuz U is used for launches of most of the unmanned Cosmos reconnaissance satellites and some Progress M space-station tankers. The U2 was used to launch other Progress Ms, a specific series of Cosmos reconnaissance satellites and manned Soyuz TM spacecraft. The Soyuz U2 was first launched in 1986, and has a record of 47 successes and no failures. The U variant - first launched in 1973 - has notched up 658 successes and 20 failures, according to figures from London-based Molniya Space Consultancy There were, however, successive failures on 14 May and 20 June.
The original Soyuz was called the Voskhod and was first launched in 1963, achieving 297 successes and 13 failures until 1976. The first designated Soyuz was launched in 1966, with 39 successes and two failures up to 1976. The total Soyuz record is 1,041 successes and 35 failures.
The Soyuz has a first stage consisting of a core stage and four similar strap-on boosters. Each strap-on is powered by four NPO Energomash RD-107 liquid-oxygen (LOX)-kerosene combustion chambers and two gimballed verniers, with a combined thrust of 1,000kN (225,000lb). The core stage is equipped with a four-chamber 940kN RD-108 engine and four verniers. Burn times are 120s and 310s, respectively, for the strap-ons and core stage.
This first-stage powerplant will be replaced by five modified RD-120 engines. The RD-120 powers the second stage of the Zenit booster. The 910kN LOX-kerosene RD-120s will be supplied by Ukraine's NPO Yuzhnoye. The burn time on the Zenit is 300s. The Soyuz's Kosberg Bureau RD-0110 300kN LOX-kerosene, second-stage engine, with a burn time of 245s, will be replaced by a new engine, details of which are not available. The Soyuz 2 will also incorporate the Zenit's inertial-guidance avionics system.
The Soyuz's sister booster, the Molniya, can place 1,600kg into a highly-elliptical orbit. It uses similar powerplants to those of the Soyuz, plus a third stage with a 67kN LOX-kerosene engine from the Korelev bureau, which has a 200s burn time. The Molniya will therefore be uprated in similar fashion, and referred to as a Soyuz 2, with a new third stage.
This could be an Energomash 20kN RD-161 or the NPO Lavotchkin Fregat. It is a 20kN multiple-restartable, nitrogen tetroxide-undemthyl-hydrazine engine, with a total burn time of 877s. The new engine has also been proposed as an upper stage for several new boosters, including an uprated Proton.
Source: Flight International
