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Explain the various rudder inspections and testing in the dry dock

a. Visual examination of the rudder plating for cracks and distortion 
b. Air plugs and drain plugs are to be opened in the presence of the class surveyor, 
repair superintendent and chief officer. Water draining out indicates a breached 
rudder and the breach to be located by air pressure testing and applying soap 
solution, repairs to be planned 
c. Check the rudder drop in the steering gear compartment (trammel gauge) 
d. Check the pintle clearances, jumping bar clearance and the palm coupling bolts 
tightness to be checked 
e. Check the rudder stock for corrosion, erosion and any damage 
f. The inspection plates in the way of the upper, the lower pintle to be cut open, and the 
pintle nuts checked for proper securing. Later the plates to be welded and tested. 
g. Hydraulic test the rudder for a static head of about 2.45m of sea water 
h. After draining and re oiling the internals, plug the drain and check the effectiveness 
by a vacuum check and cement the plug 
i. The rudder stock gland packing has to be checked and renewed

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