in the performance and operation of these systems.
Look at some of the components that have changed in
the OD box and the pitch indicating system.
OIL DISTRIBUTION BOX. On DD-51 class
ships, the configuration of the OD box has undergone
The emergency pitch pump hose
connections have been moved from the bottom of the
OD box to the low-pressure chamber cover, as shown in
PITCH INDICATING SYSTEM. A significant
change was made to the pitch indicating system. There
are now two types of pitch indicating systems installed
on DDG-51 class ships. One system is temperature
compensated while the other is electronic. Because
these two systems operate independently, DDG-51 class
ships have both a normal and alternate means of
measuring propeller pitch.
figure 3-9. This change makes it easier for the operator
Temperature-Compensated Pitch Indicator
to make the connections during testing or in case of an
System. O n D D G - 5 1 c l a s s s h i p s , t h e
temperature-compensated pitch scale platform is rigidly
Figure 3-9.Emergency pitch arrangement.