System and method for feeding at least one rocket motor

A fuel such as hydrazine is stored in a main tank (2) under nitrogen pressure (3,4). After filtering (10) the fuel is pumped (12) to booster motors (1) in parallel with supply from a small secondary tank (13) which is under sprung bellows pressure (8,15). The pump (12) is actuated by a high frequency variable reluctance mechanism and maintains a preset pressure in the secondary tank giving fuel supply to the booster motors (1).