It is not possible to combat forest fires using regular fire-fighting measures. The fire department needs support from the air for this. Like the original, SIKU fire-fighting aircraft can be filled with water. The yellow color of the signal allows fire-fighting crews on the ground to configure the fire-fighting aircraft even during thick smoke. With the press of the release button, the water from the tank goes to the ground. On the aircraft, the nose wheel can be retracted and the main landing gear can be raised.