Patent ID: 7603242

Claim:
A method of detecting a fuel leak from a fuel store, the method comprising the steps of: (i) receiving at a circuit signals representative of physical measurements made at a plurality of successive times of the amount of fuel in the fuel store of an aircraft and of the rate of fuel flowing from the fuel store, the measurements each being subject to noise, (ii) the circuit defining, in state-space, a fuel flow system state, the fuel flow state of the system being defined by a set of variables including at least one variable relating to a quantity represented by the signals received in step (i) and a variable relating to fuel leakage from the fuel source, (iii) the circuit ascertaining a new fuel flow state of the system in view of a previously ascertained fuel flow state of the system and a plurality of the measurements represented by the signals received in step (i), (iv) the circuit identifying from the new fuel flow state of the system whether there might be a fuel leakage, and, when a fuel leakage is determined, (v) causing an indication that there is a suspected fuel leak to be made.