Patent Document ID: 20130133333
Application ID: 13667220
Patent Flag: 0

Claim One:
1. A method of detecting shaft break in a shaft system ( 48 ) comprising a shaft ( 36 ) coupled between two masses ( 16 , 24 ), the method comprising steps to: Define a time-dependent rotational speed equation ( 64 ) for the shaft ( 36 ) in terms of system inertia for an engine transient event; Discretize the rotational speed equation ( 66 ) in terms of a discrete time constant (β) in the discrete domain; Recursively define ( 68 ) the discretized equation to give a recursive equation; Solve ( 70 ) the recursive equation to determine the discrete time constant (β); Define a threshold ( 74 ) as a function of engine power; and Set a shaft break detection signal ( 78 ) to TRUE if the discrete time constant (β) is less than the threshold ( 82 ).