The method includes a preliminary period in which a reference rotorcraft
is used that corresponds to a rotorcraft of a particular type, with a
series of noise measurements being performed on said rotorcraft (1) in
flight using noise sensors (C) disposed on said reference rotorcraft, and
with operating domains being determined for the reference rotorcraft in
which noise is less than a maximum noise level. Thereafter, the operating
point without wind and operating domains with wind are subsequently
determined for a rotorcraft of the particular type on the basis of
operating domains for the reference rotorcraft.