Abstract: A propulsion system for an aircraft comprises a closed cooling circuit which has at least one main segment and at least two secondary segments, in which a heat-transfer fluid circulates. Each secondary segment has: a leak detection device, a shut-off valve, and a non-return valve. The cooling circuit also has electronic circuitry configured to close the shut-off valve of a secondary segment when a leak is detected by the leak detection device of said secondary segment.

Abstract: A method for combined cooling and heating in an aircraft, the aircraft including an engine configured to use dihydrogen as fuel, the dihydrogen being stored in liquid form in a tank and being used in gas form in the engine, the dihydrogen being conveyed from the tank to the engine by a main pipe. The method includes the steps of branching off a part of the flow of dihydrogen in a bypass pipe, in parallel with a predefined segment of the main pipe, circulating a first heat transfer fluid in a first closed circuit, carrying out a first heat exchange between the first heat transfer fluid and the dihydrogen circulating in the bypass pipe and carrying out at least one secondary heat exchange. Each secondary heat exchange is carried out between the first heat transfer fluid and a working fluid used in the aircraft which needs to be cooled.