In a process and device for preventing bird-strikes on aircraft with at least one light source on the aircraft which is a discharge lamp and with a control device which varies the frequency of the light flashes generated within at least one cycle time, a simple and economic design is obtained which reduces the power losses, allocates a supply device to at least one light source consisting of at least one voltage transformer and at least one first capacitor and the voltage transformer provides a constant power at varying frequencies of the flashes generated.