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Advantage and Disadvantages of controllable pitch propeller

 Advantages of CPP

Improved Maneuverability.
Full ahead to astern un 12 seconds.
Lower ship speed can be obtained.
Crash stop feature.
Improved water flow into the rudder.
Full engine power available for astern movements.
Fewer engine starts.
Low thermal.load on engine.
Less engine wear.
Less stern tube bearing wear.
Lower starting air comsumption.
No requirement for reversing gear.
Higher engine efficiency
Pitch adjustable for hull fouling and different sea conditions
Engine power and speeds can be altered to stay clear of T/C surging zones


Disadvantages of CPP
Propellor heavier which will increase stress on tail shaft and stern tube bearings
Survey period reduced by 1 year
Additional cost during survey
Lower propellor efficiency due to large dia hub versus propeller diameter
Drop in efficiency range from 2 to 3 percent.
Increased risk of breakdown due to system dependence and greater chance of cavitation damage on propellor blades


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