Patent ID: 7907066
Filing Date: 2011-03-15
Classification: B64C

Abstract:
1. A method of detecting and signaling the approach of a vortex domain by a rotorcraft of a particular type of rotorcraft, wherein the following steps are performed in succession: a) making a series of prior measurements on a reference rotorcraft of the particular type of rotorcraft during preliminary flights by measuring a plurality of pairs of values relating to the tangential and normal components of the speed of the flow of air relative to the plane of the rotor, these pairs of values determining at least one instantaneous vortex representative of a vortex state by means of at least one diagram in which the abscissa axis and the ordinate axis correspond respectively to said tangential and normal components; b) during flight of a rotorcraft of said particular type of rotorcraft, determining in real time a predictive proper airspeed V c) defining a first detection condition specifying when said associated predictive proper airspeed V d) triggering a signaling alarm when said first detection condition is satisfied; and wherein the predictive proper airspeed V the predictive vertical speed v with: