Abstract: Airplane (1) including a mainplane (3), elevator aerodynamic surfaces (4) and a front canard empennage adjustable in orientation. This airplane includes:a device for calculating (14) continuously receiving measurements:of the speed (V) of the airplane with respect to the air,of the centering (c) of the airplane (1),of the flight altitude (H), andof the mass (m) of said airplane and calculating the angular setting to be given to said planes (5) of the canard empennage, during phases of stabilized flight without atmospheric disturbances, so that the lift of said canard empennage corresponds, at any moment, to the smallest possible value of the drag of the airplane; and a device (9) forconferring an at least substantially constant lift on said empennage when the airplane in flight is not in a phase of stabilized flight without atmospheric disturbances.