Figure 2-18.—Psychrometer: (A) Standard sling psychrometer; (B) with sling attached.
detailed instructions, refer to the handbook supplied
with the equipment.
SLING AND ROTOR PSYCHROMETERS
Sling psychrometers (fig. 2-l8) are used to backup
the electric psychrometers, both ashore and aboard ship.
Because of the widespread use of electric
psychrometers, sling psychrometers are rarely used.
Rotor psychrometers (fig. 2-19), mounted inside the
standard instrument shelter ashore, are also rarely used
as backups. Use, care, and maintenance instructions are
found in NA 50-30FR-518.
REVIEW QUESTIONS
Q16. Name the three types of psychrometers used by
the Navy?
Q17. Explain the proper use of an electric
psychrometer.
Q18. What tasks are included in the routine care of
electric psychrometers?
PRESSURE INSTRUMENTS
LEARNING OBJECTIVE: Describe the
operation of the precision aneroid barometer
and the marine barograph.
Pressure-measuring instruments are critical
equipment for surface weather observations. The ML-
448/UM precision aneroid barometer is still the primary
Figure 2-19.—Rotor psychrometer.
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