Page 27 - AFMAN 15-111, 12 MAR 2019

AFMAN15-111 12 MARCH 2019 27

5.4.1. Units may use the AN/TMQ-53 as a primary or back-up without estimating values with
the exception of winds, if all the following conditions are met:

5.4.1.1. The equipment is in good working condition (e.g., operating properly) and
properly maintained IAW the T.O. and established maintenance schedules.

5.4.1.2. The equipment is set up and operated IAW the T.O. and is sited IAW FCM-S4-
1994, Federal Standard for Siting Meteorological Sensors at Airports, Chapters 3 and 4.
Note: The AN/TMQ-53 has known sensor height exposure limitations.

5.4.1.3. The values are representative and consistent with the values from surrounding
observing sites (if available).

5.4.2. For short-term sensor outages (less than 72-hrs) weather operators may use values
obtained from other pieces of equipment (e.g., Laser Range Finders, tactical barometers, hand-
held wind readers, or other tactical meteorological equipment).

5.4.3. Weather personnel will make every attempt to promptly log out any malfunctioning
equipment unless flight safety warrants otherwise. (T-2). Exception: Do not log out the
FBWOS as the result of a system restart. Refer to AFI 21103, Equipment Inventory, Status and
Utilization Reporting, for additional information.
5.5. False Freezing Precipitation Reports. Deficiency reports for false readings exist on the
AN/FMQ19 and AN/FMQ-22 freezing precipitation sensors. Until these deficiencies are
corrected, in order to mitigate the risk of false freezing precipitation reports during airfield closure
hours, weather personnel will evaluate the risk of freezing precipitation occurring when the
temperature is, or is forecast to be between 00 and 03 degrees Celsius. (T-1).

5.5.1. Collaborate with the supporting OWS to determine if the risk of freezing precipitation
is acceptably low.

5.5.2. If freezing precipitation is expected, no additional action is needed regarding the
equipment; continue normal operations.
5.5.3. If the risk of freezing precipitation is determined to be low, the local weather personnel
will coordinate with sensor maintenance personnel to manually disable the freezing
precipitation sensor. (T-2). If the sensor cannot be disabled, weather leadership will ensure
personnel are physically present at an airfield weather services location to back-up the system’s
freezing precipitation sensor in order to prevent false freezing precipitation reports from being
disseminated, even outside controlled airfield hours. (T-2). Exception: If the sensor cannot be
disabled and is at a remote site without an airfield weather services element, back-up is not
required.

5.5.4. Log out the freezing precipitation sensor during any period where the system is
triggering false reports so the duration of each event can be tracked.