Air-safed underwater fuze system for launched munitions

Abstract

An air-safed underwater fuze system is provided for munitions that are to launch-deployed and water-detonated. A housing defines a first bore contiguous with a second bore. Radial ports in the housing communicate with the first bore. A first piston is slidably mounted in the first bore and a second piston is slidably mounted in the second bore and positioned flush with the first bore. Piston control means are coupled between the munitions and first piston for positioning the first piston in a first position prior to launch in which the first piston seals off the radial ports while being spaced apart from the second piston to define a chamber. The piston control means moves the first piston at launch to a second position so that the chamber expands and the radial ports are in communication with the chamber. The piston control means further drives the first piston from its second position towards its first position at a specified time after launch. Once the first piston seals off the radial ports, the first piston pressurizes the water in the chamber. As a result, the second piston is driven along the second bore as actuating movement. A firing mechanism is provided in communication with the second bore and coupled to the munitions. The firing mechanism is responsive to the actuating movement of the second piston to generate detonation energy for the munitions.