Abstract :
Small unmanned tethered submersibles have considerable advantages of cost and simplicity of surface handling over manned vehicles, and, since human life is not at stake, small vehicles like Angus may even be considered expendable in an emergency. It is not expected that universal agreement will ever occur on the advantages of unmanned vehicles over manned or vice versa. But the advantage of a system like Angus, where costs can be one-tenth of those involved in operating a competitive manned vehicle, is that it opens the door to many potential users with limited budgets
