Mixed propulsion system

A mixed propulsion system for a seagoing vessel comprising:

• two electric propulsion drives, each electric propulsion drive further comprising two electric control systems, wherein each control system is connected to receive electrical power from respective first and second electricity distribution switchboards;
• a gas turbine engine coupled directly to drive an electrical generator to supply electrical power to the first switchboard;
• a steam turbine engine and two diesel engines, wherein the steam turbine engine and the two diesel engines are each coupled directly to drive a respective electrical generator to supply electrical power to the second switchboard;
• the first and second switchboards being adapted to supply the power requirements of the vessel;
• and
• each propulsion drive is cross-coupled to receive power selectively from the first or second switchboard such that operation of a pre-determined arrangement of the gas turbine engine, the steam turbine engine and the diesel engines provides electrical power to both propulsion drives, and in the event of a single failure in a switchboard or an engine or both, the supply of electrical power to both propulsion drives can be maintained.