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Methane-filled heat pipes have been developed and qualified for the SCIAMACHY thermal bus assembly. The heat pipes provide an efficient heat transfer in the temperature range 100-160 K. Extensive qualification testing has been performed. The thermal bus assembly is part of the Thermal Bus Unit (TBU) of the SCIAMACHY Radiant Cooler.

The Automated Transfer Vehicle (ATV) is a European Space Agency autonomous, expendable logistic transportation system for Low Earth Orbit. The ATV will be launched by Ariane 5 and its mission is to contribute to the logistic servicing of the International Space Station: via the delivery of a cargo (crew items, scientific experiments, spare parts..) as well as of fluids such as propellant, water and compressed air via the provision of an extra service consisting of retrieving the station wastes when departing (replacing the upcoming cargo) and getting rid of them through the final destructive atmospheric re-entry of the ATV itself via the contribution to the orbit control of ISS by providing a reboost and attitude control capability to the ISS. The ATV consists of a Spacecraft and an Integrated Cargo Carrier. The Spacecraft includes all subsystems necessary for the automated flight to the ISS and for the reboost, including the propellant tanks and the thrusters.

A Heat Switch has been developed, namely a device able to autonomously regulate its own thermal conductance in function of the equipment dissipation and environmental heat sink conditions. It is based on a Loop Heat Pipe (LHP) technology, with a passive bypass valve which diverts the flow to the Compensation Chamber when needed for regulation purposes. The target application is the potential use on a Mars Rover thermal control system. The paper recalls the Heat Switch design, and reports the results of an extensive test campaign on the ground demonstrator. The performance of the device was found extremely satisfying, and often exceeded the system requirements.

Membrane gas absorption and desorption (MGA/MGD) for the removal of CO2 in manned spacecraft or other enclosed environment is subject of study by Stork and TNO for many years. The system is based on the combination of membrane separation and gas absorption. Advantage of this technology is that the system not only can be used to remove the carbon dioxide but also to control the relative humidity and temperature. Absorption of moisture and heat is achieved by cooling the absorption liquid below the dewpoint temperature of the gas stream. From the start in 1995, the Crew Transfer Vehicle is used as a basis for the design (1,2). Compared to the planned air conditioning system, consisting of a condensing heat exchanger, LiOH cartridges and a water evaporator assembly, MGA/MGD shows advantage in volume, mass and power consumption. The absorption liquid circulates through the spacecraft thermal control loop, replacing the coolant water.

The Automated Transfer Vehicle will provide ISS with reboost, attitude control functions, with water, gas and propellant and with dry cargo. It is a 20 tons expendable vehicle launched by Ariane. It performs a rendezvous and docking with the Russian Segment. It remains attached up to 6 months before a destructive reentry. During PDR campaign, it was decided to change the ATV Thermal Control System from semi-passive (see reference 1) to active system to comply with electrical power budget and get the ATV power autonomy. This system is based on 40 Variable Conductance Heat Pipes controlling the heat rejection of the avionics items toward space. This paper presents the new thermal control system of the ATV and its verification and qualification logic.

Reusability of next generation launchers needs that cryogenic insulation of LH2 and LOX tanks is able to withstand without significant degradation critical environments experienced especially during pre-launch and re-entry phases. An extensive characterisation campaign is presently on-going to improve performances of available insulations that only partially sustain thermo-mechanical loads and physico-chemical characteristics of the operative environment. The campaign is divided in two different slices: The first one has the objective of outlining the best insulation material and configuration; the second one foresses a test representative of the flight conditions performed with the selected insulation on a sub-scale Al-Li tank demonstrator. Preliminary results achieved in the frame of the first slice are presented.

The Automated Transfer Vehicle (ATV) is a European Space Agency (ESA) servicing and logistics transportation system for the periodic re-supply of the International Space Station (ISS). The ATV will be launched by Ariane 5 and will provide the following services to the ISS: refuelling of the ISS (transfer of fuel from ATV to the station), reboost of the ISS (increasing the station’s orbit altitude, using the ATV’s propulsion system), delivery of cargo such as compressed air, water and pressurised payloads to the station, destruction of waste from the station. The ATV is composed of the so-called Spacecraft (SC) and an Integrated Cargo Carrier (ICC). The Spacecraft includes the propulsion, reboost and attitude control systems, the avionics and the solar generator system.

The Minus Eighty (Degrees Celsius) Laboratory Freezer for the International Space Station (MELFI) is one of the freezers developed by ESA on behalf of NASA. Peculiar requirements for that facility are the long-term storage at low temperature, the rapid freezing of specimen to the required temperature, the large cold volume (300 l) and the low power consumption. To verify those requirements before the manufacturing of the flight hardware, a dedicated test campaign was performed on a ground model. This paper will start with a system overview, showing the main features of MELFI. The test set-up as well as their results will be presented and discussed, with particular emphasis on the methods used to predict the on-orbit (0-gravity) behaviour, by avoiding the sample internal convection and dewar internal convection during the test execution.