In one aspect, the invention is directed towards a helicopter-carned firefighting device including a valve. The valve has an outer assembly and an inner assembly in which the outer assembly has a reduced surface area on those surfaces which are disposed normally to a direction of movement. The outer assembly therefore may be les s affected by hydrostatic and hydrodynamic forces directed so as to oppose its movement. The valve may be located in a reservoir of fluid, and controlled b y a control head operated remotely from the helicopter so as to release fluid fr om the reservoir over a fire. The valve may be symmetrical about a longitudinal axi s of the valve, such that transversely directed fluid flows through the valve may be cancelled, producing a coherent, longitudinal fluid flow. The valve may be opened partially so as to operate as a metering valve. The valve may be closed relatively rapidl y to retain fluid in the reservoir so as to permit multiple dumps from a single reservoi r if so desired. -24-
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