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
several changes.
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
emergency.
temperature-compensated pitch scale platform is rigidly
Figure 3-9.—Emergency pitch arrangement.
3-13
