NOTE: The ID-2447/U indicator (fig. 2-25) is a
recent addition to the UMQ-5 system. The indicator is
found in weather offices and in Marine Corps radar
support spaces, with the primary readout in the Air
Traffic Control Center. The indicator provides average,
minimum, and maximum wind speeds. For more
information on the ID-2447/U indicator, see the
operating and maintenance instructions.
Typically, the wind speed and direction indicators
and wind speed recorders are installed inside the
weather office, while the transmitter is installed on an
MT-535/UMQ-5 support mast near the runway or on a
Operation and Maintenance
Operation and maintenance instructions for the
different components of the AN/UMQ-5 wind-
measuring set are detailed in several manuals. Consult
the manual for the model installed in your office.
NA 50-30FR-525, the Handbook of Operation and
Maintenance Instructions for Wind Measuring Sets
AN/UMQ-5C and AN/UMQ-5D, covers the newer
models, including instructions for the later model RD-
108(B) chart recorders. NA 50-30FR-501 covers the
AN/UMQ-5(A) system, and NA 50-30FR-512 covers
the AN/UMQ-5(B) system. Instructions for the older
model recorders (RD-108/UMQ-5 and RD-
108(A)/UMQ-5) are covered in NA 50-30FR-505, the
Handbookof Operation and Service Instructionsfor the
Wind Direction and Speed Recorder RD-108/UMQ-5.
TRANSMITTERS AND INDICATORS.Very
little operator attention is required for this equipment.
The operators handbook recommends a daily visual
check of the transmitters and indicators, and a weekly
Figure 2-25.ID-2447/U wind speed and direction indicator.
visual inspection of the transmitter. Jerky movement of
the impeller or failure of the wind vane to follow light
winds indicates an overhaul is due. Finally, a quarterly
friction check is recommended. The transmitter is
removed and bench tested with penny and half-dollar
weights to check for excessive friction.
WIND RECORDER.The analog wind recorder
requires somewhat more attention. The recorder pens
mark a continuous output of wind direction and wind
speed on a continuous, two-column chart (fig. 2-26).
The wind direction column, on the left side of the chart,
has vertical lines drawn for every 10 degrees; these are
labeled every 90 degrees, along with the cardinal
compass points. The chart covers 540 degrees to allow
for shifting winds. The wind speed column, on the right
side, has vertical lines drawn every 2 knots; these are
labeled every 20 knots, from 0 to 120 knots. Curving
lines across the chart mark the time every 10 minutes
and are labeled for every hour, in the center divider
Many recorders have been modified to use preinked
pen cartridges, which are simply replaced as a unit when
the ink runs dry. Some units still use the older model
pens and inkwells. The older pens must be checked
frequently; a line that skips on the chart usually
indicates a dirty pen.
A standard, 100-foot, wind speed and direction
recorder chart, when operated at the standard speed of 3
inches per hour, will run for 15 to 16 days before it
requires changing. Instructions on how to replace the
chart in the recorder are contained in the handbook on
operation and maintenance.
The analog recorder charts should be carefully
preserved and treated as a permanent official record.
Each recorder chart roll should be identified at the start
and end of the roll, with the station name and the date
and time the recording began and ended. The chart is
adjusted so the times marked on the chart correspond to
UTC. The chart should be changed at 0000 UTC on the
first day of each month and at intermediate times to
prevent the loss of data. See NAVMETOCCOMINST
3141.2 for more information.
TIME CHECKS.Time checks are made on the
recorder chart by drawing a short line on the recorder
chart where the pen is marking data, and entering the
date and time to the nearest minute. At the minimum,
time checks are required as follows:
At the beginning and end of each chart roll