Patent ID: 7149646

Claim:
A pilot indicator for a rotorcraft provided with a main rotor and at least one gas turbine engine, the indicator comprising: first and second sensors delivering information relating respectively to a first speed of rotation Nr corresponding to the main rotor and a second speed of rotation NTL corresponding to the free turbine of said engine; processor means for processing the information from said first and second sensors; and display means provided with a display screen for displaying the first and second present values respectively of the first and second speeds of rotation Nr and NTL, wherein said processor means determines an estimated value for the first speed of rotation Nr, and wherein, during acceleration of the engine, said processor means determines said estimated value from the following predictive relationship in acceleration, in which IPT, Nr, k, and dNr/dt correspond respectively to said estimated value of said first speed of rotation, said first present value of said first speed of rotation, a multiplier coefficient, and the variation of said present first value during a time interval: IPT = Nr + ( k ⁢ ⅆ Nr ⅆ t ) 4 .