5.2.2 The
generating and distribution system is to be so arranged that after
any single failure, steering capability can be maintained or regained
within a period not exceeding 45 seconds, and the effectiveness of
the steering after such a fault will not be reduced by more than 50
per cent. This may be achieved by the parallel operation of two or
more generating sets, or alternatively when the electrical requirements
may be met by one generating set in operation, on loss of power, the
automatic starting and connection to the switchboard of a standby
set, provided that this set can restart and run a thruster with its
auxiliaries.
5.2.3 The
failure of one thruster unit or its control system is not to render
any other thruster inoperative.