The invention relates to de-icing and anti-icing procedures performed on airplanes on the ground, wherein a fluid is sprayed from the boom or arm of a de-icer installation onto the aircraft. A spray-regulating system is incorporated in aircraft anti-icers comprising a tank (1) with anti-icing fluid, a fluid pump (2) with a drive motor (6), and a hose or pipeline (7) between the pump (2) and a spray nozzle (3) located on an elevating boom, arm or operator's platform so that the fluid can be pumped from the tank (1) to the spray nozzle (3), said system further comprising a central control unit (5), a pressure-signal-generating pressure sensor (4) located proximate to the inlet of nozzle (3), and a regulating device (8) for the motor (6) to adjust the motor momentum, wherein a constant pressure upstream of the nozzle (3) and consequently over said nozzle (3) is maintained by said control unit (5) producing a signal calculated on a pressure signal received from the sensor (4) and the pressure required upstream of the nozzle (3), and said signal being transmitted to the regulating device (8), which then adjusts the momentum of the pump motor (6) and thereby adjusts the flow rate and or pressure rate in the pipeline (7).