INTRODUCTION

9.1 Whilst all vehicles and ships have operating systems, the submarine requires special systems to enable it to operate in its environment between the surface and fully submerged below the sea. The systems are required both for operation in underwater space and for the crew to work efficiently totally divorced from the atmosphere. In concept formulation and initial sizing the systems do not present issues that need to be considered in detail, though they do require provision of space and weight within the hull. Nevertheless, since they are so important to the general operation of the vessel, we devote this chapter to describing particular aspects of submarine systems, how they are operated and the usual form taken by their design. A particularly important aspect of the systems is their integrity and reliability.

The primary systems in a submarine can be categorised under the following headings, though in some cases they overlap:

1. (a) Hydraulic systems – these are provided for power actuation of many valves, systems and controls.

2. (b) High pressure air system – this is required mainly to initially discharge water from the main ballast tanks in changing from submerged to surface condition, but it also has many other uses on board.

3. (c) Water distribution systems – these are required to control the trim of the boat and to eject unwanted water taken on board during various operations.

4. (d) Ventilation and air-conditioning systems – these are distinctive in a submarine because of the special needs of the enclosed atmosphere once submerged.