An aircraft having wheels with hydraulically-actuating friction brakes and independent drives for driving the wheels in rotation and enabling the aircraft to move in stages of independent drive when engines of the aircraft are inactive. A main hydraulic circuit with a pressure source powers the brakes when the pressure source is active; with an alternative braking circuit for enabling the brake system at least when the engines of the aircraft are stopped. The alternative braking circuit includes an accumulator that is used for parking braking and is kept under pressure by the pressure source of the main circuit when the pressure source is active. An auxiliary hydraulic circuit pressurized by an auxiliary pump and power system enables the independent drives to be actuated. The auxiliary hydraulic circuit is connected to the alternative braking circuit to maintain an operating pressure in the accumulator of the alternative braking circuit.