US Patent 10139007 Material spreader apparatus for a helicopter

A material spreader which is suspended beneath an airborne helicopter and which includes a container for flowable materials such as seeds, fertilizers or chemicals. The container has a discharge opening formed in its lower end which has a vertically movable valve positioned therein. The valve is controlled by the pilot of the helicopter from within the cockpit of the helicopter so that the application rate of the material may be varied without the necessity of landing the helicopter.