Patent ID: 8843252

Claim:
A method of assisting the piloting of a hybrid aircraft having a rotary wing and at least one propulsive propeller, the method being characterized by the following steps: determining, by a processor, at least one thrust margin (ΔP) for said propeller between a current thrust (P 2 ) exerted by said propeller and a threshold thrust (P 1 ) corresponding to a negative thrust limit (Pmin) authorized on a mechanical transmission driving the propeller; determining, by the processor, a main minimum total ground slope (γ min ) that can be followed by the aircraft in descent as a function of said thrust margin (ΔP); and presenting on a display unit a main symbol for the minimum total ground slope that can be followed by the aircraft in descent, this main symbol being a function of at least the main minimum total ground slope (γ min ) and appearing superimposed on a representation of the surroundings existing in front of the aircraft, wherein in order to determine said thrust margin (ΔP), the following steps are performed: determining a current forward speed of the aircraft; determining a current power (W 2 ) developed by said propeller; determining the current thrust (P 2 ) exerted by said propeller by using a first predetermined database giving the current thrust (P 2 ) as a function of said current forward speed and of said current power (W 2 ); determining said threshold thrust (P 1 ) by using a second predetermined database giving said threshold thrust as a function of said current forward speed; and determining said thrust margin (ΔP), said thrust margin being equal to the difference between the current thrust (P 2 ) and the threshold thrust (P 1 ).