Abstract: A hydraulic pump driven by any suitable power source, such as by an electric motor energized from a storage battery supplies water under hydraulic pressure by way of a control valve unit to a plurality of pairs of downwardly and outwardly-inclined nozzles disposed at various locations around the boat's hull above the water line thereof. These include a forwardly-located pair of nozzles on the starboard and port sides respectively and also three pairs of nozzles near the stern of the boat, the first pair upon the starboard and port sides being directed downward and forward for backward maneuvering, the second pair being directed downward and outward on the starboard and port sides respectively for side-wise maneuvering, and the third pair being directed downward and rearward also on the starboard and port sides for forward maneuvering. A first modification makes use of a downwardly and rearwardly directed nozzle with an optional flow-reversing deflector amidships on the transom of the boat.

Abstract: For holding while machining the end enlargement or enlargements of an elongated otherwise thin deformable workpiece, such as a jet engine blade, the lower block of a two-part hinged fixture has mechanically-adjustable stops which predetermine the location of the front edge and front end of the thin portion of the workpiece and has three upwardly-inclined support pins upon which the lower surface of the thin portion rests. An upper block hinged to the lower block contains three downwardly-inclined correspondingly located clamping pins which bear upon the upper surface of the thin portion immediately above the lower support pins. Each block contains horizontally-movable forward and rearward hold-fast pins for the workpiece end enlargements.