The rudder indicator measures the rudder angle continuously and the measuring accuracy in the range of +/- 0.5° at angles near midships and +/- 1.5° at hard over rudder, Sperry (1995).
The rudder movements are shown under operating conditions (ME Power pct. > 30%)
Reasons for a permanent offset of the rudder during service could be:
– An index error in the rudder angle measurement device.
– A permanent rudder angle counteracting the turning effect of the right-hand propeller.
– A permanent yawing effect induced by the ship’s hull or by the wind effect on the superstructure and container cargo during sailing.
