pressure altitude from pressure and air temperature, and
to compute density altitude using the pressure, air
temperature, and dew-point temperature. It may also be
used to compute density ratio, absolute density, vapor
pressure, and specific humidity. Detailed instructions
for the computation of pressure altitude and density
altitude are printed on the back of the calculator.
CP-264/U TRUE WIND COMPUTER
The CP-264/U true wind computer (fig. 2-49) is
used to convert relative wind direction and speed to true
wind direction and speed, using the ships heading and
speed. It may also be used to compute ships course and
speed, necessary to obtain a relative wind direction and
speed across the deck for aircraft operations. The inputs
for this calculation are the actual (true) wind speed and
direction, and the required relative wind speed and
direction. Detailed instructions for use are printed on
the back of the computer and in NA 50-30FR-523.
NAVMETOCCOMINST 3144.1 also contains
information on the use of the CP-264/U calculator.
Throughout this chapter we have discussed
"backup" equipment for primary-use observation
equipment. You will occasionally need to use the
backup equipment when your primary equipment fails.
Figure 2-49.CP-264/U true wind computer.
You will then need to begin repair of the primary system
that has become inoperative. In the next section, we
discuss equipment maintenance and repair.
What is the purpose of the CP-402/UM
What values may be computed by using the CP-
Which calculator is used to compute vapor
pressure and specific humidity?
Besides true wind direction and speed
calculations, what additional information can be
obtained from the CP-264/U True Wind
LEARNING OBJECTIVES: Describe
procedures to be followed during equipment
outages. Recognize the resources available for
equipment maintenance and repair assistance.
Identify the basics of the Navys Maintenance
and Material Management (3-M) program.
Equipment outages will occur from time to time. In
this section, we briefly discuss what should be done
when equipment becomes inoperative, and the
technicians that will provide maintenance and repair.
We also briefly discuss the Navys preventive
An equipment outage occurs when a device is not
available for use. Equipment outages can be caused by
power failure, equipment breakdown, or planned
maintenance. All equipment outages should be entered
in an equipment outage logbook. Logbooks should be
maintained for each major equipment system, such as
ASOS, SMOOS, AN/GMQ-32, AN/GMQ-13, and the
AN/UMQ-5. These logbooks should contain, at the
minimum, the date and time the outage began and
ended, the reason for the outage (if known), and the
name of the person making the entry. Logbooks serve
as an important tool for maintenance personnel. Notify
your supervisor or section leader of all equipment
outages. Your supervisor may then ask you to contact