ISS Propulsion Module

The ISS Propulsion Module (IPM, engl. , About ISS-drive module ) was as a substitute solution for the Swesda module of the International Space Station and the Progress provided transporter. Instead, only the Russian modules Zvezda and Progress, supported from 2008 to 2015 by the European Automated Transfer Vehicle Automated Transfer Vehicle, are used for important functions such as location determination, navigation , control and propulsion. If the Zvezda module had been lost on startup or if its start had been delayed, the IPM would have been used. This would have enabled the ISS to regulate its altitude and position, have had a fuel tank and could have avoided approaching space debris. Before using the IPM, however, the Interim Control Module would have been started first , but it only has a maximum service life of three years.

The ISS needs an average of 7,000 kg of fuel every year to maintain altitude, for evasive maneuvers and to maintain position. Several supply flights per year are required to meet this demand. An IPM could have provided reserve fuel for a year if the supply had been interrupted.

The IPM should hold about 9808 kg of fuel. In comparison, a Progress-M spaceship can hold 1200 kg and a Progress-M1 spaceship 1950 kg. The Automated Transfer Vehicle to the ESA summarizes 4700 kg and that does not just come to use ICM could carry 5000 kg of fuel. With the space shuttle , the height of the ISS was typically raised with 232 kg of fuel, but depending on the mission also with up to 1626 kg. The Zarya module of the ISS holds 5500 kg of fuel and the Zvezda service module holds 860 kg of fuel. However, attempts are generally made to keep the main engines of both modules as a reserve, as they have a limited service life.

In addition to being used as a replacement for the Zvezda module of the ISS, the IPM was also intended as a separate US drive option and could have supplemented the ISS later. However, there were budget overruns and delays in planning. The "Node-X" design was considered as an alternative. An improperly fabricated hull, which was actually intended for the Harmony or Tranquility module , would have been used for this. Two removable fuel tanks that would have been transported with a space shuttle should be used. Replacing the tanks would have avoided problems with pumping fuel between tanks in space. The Node-X was later deleted from the plans, instead the ISS has to rely on the propulsion system from Progress (formerly also ATV). In the course of the shutdown of the shuttles, a further redesign would have been necessary.