Abstract: A fluid drop system for an aircraft for use in firefighting is described. The preferred embodiment uses electronic control circuitry coupled with a hydraulic controller that opens and closes the fluid tank's door panels to rate-control fluid drops based on fluid volume remaining in the tank. The circuitry produces a command generated drop rate profile based upon manual drop rate and drop fraction selector controls. It does so by constant comparison of the instantaneous volume of fluid remaining in the tank with a predetermined, desired instantaneous remnant volume in accordance with a defined, declining-volume profile, e.g. one defining a constant drop rate. A stabilized feedback control circuit ensures that, at any instant of time, the opening in the tank's door panels releases a volume of fluid that will maintain the remnant tank volume equal to the desired tank volume.

Abstract: A fluid drop system for an aircraft for use in firefighting is described The preferred embodiment uses electronic control circuitry coupled with a hydraulic controller that opens and closes the fluid tank's door panels to rate-control fluid drops based on fluid volume remaining in the tank. The circuitry produces a command generated drop rate profile based upon manual drop rate and drop fraction selector controls. It does so by constant comparison of the instantaneous volume of fluid remaining in the tank with a predetermined, desired instantaneous remnant volume in accordance with a defined, declining-volume profile, e.g. one defining a constant drop rate. A stabilized feedback control circuit ensures that, at any instant of time, the opening in the tank's door panels releases a volume of fluid that will maintain the remnant tank volume equal to the desired tank volume.

Abstract: Apparatus for use in an aircraft, such as a helicopter, for controlling rotation of a load suspended from a cable and for permitting the cable to swing relative to the helicopter. A frame includes a first or upper assembly which is mounted on the helicopter for pivotal movement about a first pivot axis. The frame also includes a second or lower assembly connected to the upper assembly which is pivotal about a second pivot axis extending transversely to the first pivot axis. A spreader bar is suspended within the frame and is isolated during helicopter pitch and roll. Helicopter yaw imparts positioning of the spreader bar relative to a vertical axis so that the load may be selectively oriented.

Abstract: An improved angle guide for use in directing a first structural member toward a position adjacent a section structural member. The angle guide includes a flange and set screw assembly for clamping to the second structural member. A brace extends from the angle guide for engagement with the second structural member for preventing rotation of the angle guide when it is under load.