United States Marine Corps Weapons & Equipment
AN/TMQ-31 Meteorological Data System
Primary function: To provide raw meteorological data.
Manufacturer: Flight Line & ETG
Length: 28.86 feet (8.97 meters) (mounted on M925 truck)
Width: 8.21 feet (2.5 meters) (mounted on M925 truck)
Height: 11.86 feet (3.61 meters) (mounted on M925 truck)
Weight: 90,000 pounds (40,860 kilograms) (mounted on M925 truck)
Wind speed:
NAVAID: less than 2 to 5 knots (2.3 to 5.75 miles per hour)
RDF: less than 4 knots (4.6 miles per hour)
Positioning:
LORAN: +/- 30 meters (98.43 feet)
VLF/Omega: +/- 200 meters (656.2 feet)
Azimuth/Elevation: +/- 0.05°
Temperature: 0.5° C (41° F)
Pressure: +/- 2 millibars
Humidity: 3 percent
Power: 230 Volts, AC, Single Phase, 50-60 Hz, 10 KW
Units: HQ Btry Artillery Regiments, Meteorology Section
Crew: 7 enlisted
Introduction date: April 1988
Unit Replacement Cost: $1,400,000
Mission: To provide meteorological data to artillery units such as wind speed and direction, humidity, temperature
and pressure.
Features: The AN/TMQ-31, Meteorological Data System is an Army-developed system which provides raw meteorological
data to a variety of users, primarily the field artillery. It consists of automated electronics components housed
in an S-280 shelter. It is capable of tracking radiosondes by NAVAIDS or RDF mode, and pilot balloons with an electro-theodolite
for visual flights. The basic system requires a large array of external supporting equipment, including: an AN/TMQ-4A
system for balloon inflation and launch operations and surface measurements; two MEP003 power units and an M353
trailer; a 400-gallon water tank/trailer; an RDF antenna and modified M105 trailer; three five-ton 6x6 cargo trucks;
and a crew of seven.
The AN/TMQ-31 MDS is capable of using NAVAIDS (LORAN, Omega, VLF/Omega, RDF) or manual modes in the acquisition
of meteorological data. Automatic operations using NAVAIDS extend to 75 kilometers (46.56 miles) with a dipole
antenna, and 165 kilometers (102.46 miles) with a reflector antenna. Automatic RDF operations extend to 160 kilometers
(99.36 miles) using a dish antenna, and manual operations are limited to available ceiling/line-of sight. The system
can be operational in 15 minutes (NAVAID) or 30 minutes (RDF).
Inventory: 18
Background: The Army developed the AN/TMQ-31 Meteorological Data System during the early to mid-1980s to replace
the antiquated AN/GMD-1B Rawin Set as the source of meteorological data for the field artillery and other target
acquisition assets. While the Marine Corps did not fully support the Army's requirements (too heavy, bulky, etc.),
developing a system unilaterally was not feasible.
Information and Photos Courtesy of United States Marine Corps
