amphibious fire-fighting aircraft
Airplane with large water tanks; it is used to fight forest fires.
float 
Watertight structure that prevents the airplane from tipping when it fills its tanks.
water-tank area 
Area with a hatch that scoops up water from the surface of a body of water to fill its tanks so that it can dump the water in flight.
three-blade propeller 
Propulsion device with three blades that are arranged around an axle and driven by a motor.