Powertrain for an amphibian

A power train for an amphibian operable in land and marine modes, the power train comprising:

• a prime mover having an integral speed change transmission;
• at least a first land propulsion unit;
• at least a first marine propulsion unit;
• a power transmission unit including a drive member configured to couple the prime mover to the at least first marine propulsion unit, wherein:
• the prime mover is arranged to drive the at least first land propulsion unit through/via the integral speed change transmission in the land mode;
• and
• the prime mover is arranged to drive the at least first marine propulsion unit through/via the power transmission unit in both the marine mode and the land mode;
• and
• a second marine propulsion unit, wherein the prime mover is arranged to drive the second marine propulsion unit through/via the power transmission unit in both the marine mode and the land mode;
• wherein a crankshaft or other drive shaft of the prime mover is arranged to drive the at least first and/or a second marine propulsion unit(s) through/via the power transmission unit, and drive is not provided through/via the integral speed change transmission on the prime mover;
• and
• wherein the power transmission unit provides a fixed input/output ratio.