System for elaborating an alarm signal on board an aircraft in the event of a mini-tornado

Claim 1

System for elaborating on board an aircraft alarm signal in the event of a mini-tornado, comprising a computer device (11) which obtains signals representative of the velocities of the horizontal wind and of the vertical wind, to which said aircraft is subjected, from information on velocities, trim and incidence delivered by the on-board anemometric system (12), inertial system (13) and aerodynamic incidence sensors (15), respectively, of said aircraft, characterized in that is comprises: derivation means (23, 24, 25) for calculating the derivative of the signal representative of said velocity of the horizontal wind with respect to time; first means (30, 31, 32) for forming a first signal representative of the positive values of said derivative; second means (27, 28) for forming a second signal representative of the negative values of said derivative; first summation means (29, 33, 38) delivering a third signal obtained by the addition of said signal representative of said velocity of the vertical wind and said first and second signals and by the subtraction of a signal representative of the mean velocity of the horizontal wind during a period prior to that of the operations effected by said system; second summation means (48) for forming the sum of said incidence information and of said third signal; means for comparing said sum and a predetermined threshold of incidence guaranteeing a minimum safety energy of the aircraft; and alarm means capable of emitting an alarm signal when said sum is greater than said predetermined threshold of incidence.