Flag Gambia / Banjul. Built 1974 / Robb Caledon, Leith. GT 1088 L 67,47 B 13,75 D 2,41 356 passengers 32 cars Propulsion 1 x Mirrlees ETSL16M.
It is an unusual engine in itself, in that each unit comprised two 8 cylinder engines built as a combined unit side by side. Their crankshafts were joined together by gears in a gearing case which stepped up rotation speed from 750rpm to 1000rpm and then drove at that speed on a single shaft into a reverse/reduction gearbox driving variable pitch propellors by J.B. Berg, a Norwegian engineering firm.
The reason for the twin engine unit design was simply to obtain a substantial amount of power from a compact engine for which there was very little engine room space. There, headroom was limited, but as a car ferry, she had ample lateral space to accommodate these wider engine units.
The engines were rated (each combined unit) for 1700bhp at 750rpm and though her designed speed at 85% power was 15.8 knots, she achieved a best mean speed of 16.54 knots on trials. Most of her life, she was operated at around 660 - 680rpm, well within her capability, and her emissions were remarkably clean.
John Kemplen told this details to me. Thank you, John.