On the other hand, if the pitch pointer and the scale
difference is less than a 1/16 of an inch or the greater
than reading is related to thermal growth or contraction,
then the scale can be moved to match the pointers
position. The only drawback to adjusting the scale to
match the pointer is that an electronic alignment
(calibration) must be performed
ELECTRONIC ALIGNMENT. The electronic
alignment procedures differ depending on the ship class.
But, one thing will always be the same. To accomplish
any of these procedures, the ship must be in dry dock or
you will require the assistance of a diver. All
adjustments made to align the mechanical (actual) pitch
and electronic display indications must be verified with
the actual blade position on the propeller hub. There is
one electronic alignment procedure (electronic pitch
indicating [EPI] system calibration) on the DDG-51
class that can only be accomplished when the ship is in
dry dock.
REMOVAL AND REPLACEMENT OF
COMPONENTS
The CRP/CPP system seldom requires the removal
or replacement of components. However, there is one
component that you will be required to replacethe
electrohydraulic servo valve. As previously discussed,
this valve is in constant use and its probability of failure
is much higher than any other component in the system.
There is only one other set of components that you
will need to remove frequentlythe systems filters. In
fact, you will need to remove these filters even more
frequently than the electrohydraulic servo valve. This
is because you will need to remove the filters for
periodic cleaning according to the PMS. Of course, you
will also need to remove them in the event of a casualty.
SUMMARY
In this chapter, we have discussed many of the
factors that affect GTE performance, power train
operation and maintenance, and propulsion systems. As
you prepare for advancement, you must continue to
learn and increase both your leadership skills and
technical expertise. You must be prepared to train and
supervise your subordinates. Read the various
reference materials cited in this chapter to increase your
understanding of the information that was presented.
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