Slide 62 of 99
Notes:
The Russian FGB space tug is the cornerstone of the new International Space Station since it acts as an adapter between the US and Russian-built ISS segments and also provides some propulsion & propellant storage capabilities. It is closely based on an older Russian spacecraft design that was used on the Mir and Salyut 6,7 space stations. The United States paid $220 million for the FGB (vs. $450 million for Lockheed's rejected “Bus-1” option) and the Russians successfully completed the project on schedule and within budget. However, the launch had to be delayed by 17 months to November 1998 because the Russians were unable to complete their own modules on time.
FGB-derived "space tug". The Russian aerospace industry has recently
been investigating commercial derivatives of the FGB module as an alternative
to Progress. This design would be fully compatible with unmanned 18.3 x 4.5
meter U.S. Space Shuttle payloads. The vehicle would be launched on a Proton
booster and could carry as much cargo as four Progress spacecraft.
Improved space transportation capabilities were a major reason for bringing the Russians on board. NASA decided to use the existing 3-man Soyuz spacecraft as an interim “lifeboat” for the Space Station while investigating more capable alternatives. The Russians also promised to provide -- and pay for -- cheap unmanned cargo transportation. However, the modified Progress M and MT versions shown here were never built in the end. Russia is still going to launch four standard Progress craft per year, but many Western observers now doubt the Russians will be able to deliver on those promises. The Russian Space Agency is strapped for cash and keeping the existing Mir space station in orbit will further drain resources from the International Space Station.
