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Aviation Glossary :: ASOS  Aviation Glossary :: ASOS FAA Written Test Preparation
Aviation Glossary Welcome to the Dauntless Aviation Glossary!

At Dauntless, our editorial staff maintains the web's largest unified glossary of aviation terms. This glossary is built from a combination of official, quasi-official, and proprietary sources (including original material that we develop oursselves). Uniquely, we often provide multiple definitions of a given term so that you can find that which best applies to you. In order to maximize your learning efficiency, this glossary (and similar ones for our international users) is incresingly fully integrated into our aviation learning apps, including our FAA written test prep and FAA practical test prep software and apps. If you like this glossary, you'll love them with their polished learning environments and world's best and clearest content (please do give them a try.).

A weather observing system that provides minute-by minute weather observations, such as temperature, dew point, wind, altimeter setting, visibility, sky condition, and precipitation. Some ASOS stations include a precipitation discriminator that can differentiate between liquid and frozen precipitation.
source: FAA Instrument Procedures Handbook (FAA-H-8083-16)
Weather reporting system which provides surface observations every minute via digitized voice broadcasts and printed reports.
source: FAA Pilot's Handbook of Aeronautical Knowledge (FAA-H-8083-25A)
Weather reporting system which provides surface observations every minute via digitized voice broadcasts and printed reports.
source: FAA Risk Management Handbook (FAA-H-8083-2)
Automated Surface Observing System (ASOS): Weather reporting system which provides surface observations every minute via digitized voice broadcasts and printed reports.
source: FAA Weight Shift Control Handbook (FAA-H-8083-5)
The Automated Surface Observation System, in the United States, is a surface weather observing system implemented by the National Weather Service, the Federal Aviation Administration and the Department of Defense. It is designed to support aviation operations and weather forecast activities. The ASOS provides continuous minute-by-minute observations and performs the basic observing functions necessary to generate an aviation routine weather report (METAR) and other aviation weather information. ASOS information may be transmitted over a discrete VHF radio frequency or the voice portion of a local navaid. A
source: ICAO Aviation Chart Glossary
Automated Surface Observing System. A list of stations currently active and available through the NWS website can be found here.
source: NOAA National Weather Service Glossary

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