Airport Weather Systems

AWOS Sensor for Airport Weather Observation

Measured inputs for automated aviation weather reporting

Wind, Temperature, Pressure & VisibilityPresent Weather & PrecipitationMatched to the AWOS Architecture

AWOS sensors collect the meteorological and environmental data that the Automated Weather Observing System monitors, processes, displays, records and makes available to associated airport systems. Sensors are selected for parameters, accuracy, environment, interface, power and mounting.

Supported by Precision AGL Solutions

AWOS Sensor

What It Is

AWOS (Automated Weather Observing System; ICAO documents call it an automatic meteorological observing system) sensors are measurement devices within the observing system. They give measured inputs to the AWOS processing system, where parameters are monitored, processed, displayed, recorded and made available to associated airport weather and information systems.

Precision AGL Solutions supports AWOS sensor configurations selected for required parameters, accuracy, environmental conditions, communications interface, power, mounting and project specification.

Typical Uses

  • Airport and runway weather monitoring
  • Automated weather observation and aviation weather reporting
  • Integrated airport weather networks, airfield environmental monitoring
  • General aviation weather stations
  • Expansion, modernization, replacement and upgrade of weather sensors

Selected for Operational Requirements

Weather monitoringAirport meteorological monitoring and runway weather monitoring.
Automated reportingAutomated weather observation systems and aviation weather reporting.
Integrated networksIntegrated airport weather networks and airfield environmental monitoring.
Operational supportRunway operational support and general aviation weather stations.
ProjectsAirport expansion and modernization projects.
ReplacementReplacement and upgrade of existing weather sensors.

Select the final sensor combination from the airport's operational requirements and the parameters the associated weather observation system needs.

Configuration-Specific Sensor Selection

WindWind speed and wind direction.
Temperature & humidityTemperature and relative humidity.
PressureAtmospheric pressure.
VisibilityVisibility measurement.
Present weather & precipitationPresent weather and precipitation.
Cloud & otherCloud information and other site-specific parameters.

Not every installation needs all parameters. Base selection on the approved system architecture and project requirements.

A Typical AWOS Installation

Sensors

  • Wind, temperature, relative humidity and barometric pressure sensors
  • Visibility, present weather and precipitation sensors
  • Cloud-height measurement equipment where required
  • Sensor mounting structures

Processing & Support

  • Data acquisition equipment, AWOS processor
  • Communications interface, local display or operator interface
  • Power supply, surge and protection equipment, associated cabling

Specification Overview

ParameterSpecification
Product typeAWOS Sensor
ApplicationAirport weather observation
Measured parametersConfiguration-specific
Measurement accuracySensor/model-specific
Measurement rangeSensor/model-specific
ResolutionSensor/model-specific
Response timeSensor/model-specific
Output interfaceConfiguration-specific
CommunicationsProject/system-specific
Power supplySensor/model-specific
Power consumptionSensor/model-specific
MountingPole, mast, structure or equipment-specific
Environmental protectionOutdoor aviation environment
Operating temperatureModel-specific
Operating humidityModel-specific
Enclosure protectionModel-specific
Cable interfaceConfiguration-specific
DimensionsModel-specific
WeightModel-specific
CalibrationAccording to sensor/system requirements
MaintenancePeriodic inspection and calibration as applicable

Confirm exact range, accuracy, resolution, power consumption, protocol, environmental rating, dimensions and mounting details against the selected sensor model and AWOS configuration.

Begin With the Measured Parameter

Selection Criteria

  • Required parameter, range, accuracy, resolution
  • Environmental conditions, response time
  • Data output, communication protocol, power supply
  • Mounting arrangement, cable length
  • Maintenance and calibration requirements
  • Compatibility with the AWOS processor

Principle

Do not select sensors independently of the overall AWOS architecture, because communication, power, data processing and mounting interfaces must operate together.

Wind Speed and Direction

Provides

  • Wind speed and wind direction
  • Inputs from which the AWOS processor derives mean wind, gusts and direction variation
  • Response and measurement performance suited to the aviation application

Mounting

Provide appropriate exposure to the wind while avoiding interference from buildings, structures, trees or other obstructions. Wind sensors are normally mounted about 10 m above ground and sited to represent conditions along the runway and at the touchdown zone.

Reporting basis: ICAO Annex 3 uses a 2-minute average for local routine and special reports and ATS displays, and a 10-minute average for METAR and SPECI. Wind direction is reported in degrees magnetic in local reports and in degrees true in METAR and SPECI, so the sensor north alignment and the magnetic variation entered in the processor must both be correct. Confirm against your current Annex 3 edition.

Environmental Information

May Measure

  • Air temperature
  • Relative humidity
  • Associated calculated meteorological parameters

Positioning

Position and shield the assembly to minimise the influence of direct solar radiation and nearby heat sources. Sensors normally sit in a radiation shield, naturally or mechanically aspirated, at about 1.25 to 2 m above ground, away from paved surfaces and exhaust sources.

Pressure Information for the AWOS

Use

Pressure measurement may be used for aviation meteorological reporting and associated calculations.

Configuration

Install and configure according to the required reference elevation and system design. QNH and QFE are computed from station pressure, so the barometer elevation and the aerodrome or threshold elevation must be entered correctly. Annex 3 reports both in hectopascals, rounded down to the whole hectopascal.

Optical Measurement Where Required

Optical Measurement Can Be Affected By

  • Obstructions, local light sources
  • Dust, contamination
  • Precipitation, environmental conditions

Installation

The sensor provides data for AWOS processing. Follow the applicable system and airport requirements for the installation arrangement. A visibility sensor measures meteorological optical range and is not a substitute for RVR, which is derived from the extinction coefficient, runway light intensity and background luminance (ICAO Doc 9328). Where the runway needs RVR, specify an RVR system.

Precipitation and Atmospheric Conditions

Capability

Where required, provides information on precipitation and atmospheric conditions. Depending on equipment, the system may support detection or classification of weather phenomena relevant to airport operations.

Configuration

Exact parameters and reporting capability depend on the sensor model and AWOS configuration.

Verify Against the AWOS Processor

Important Considerations

  • Communication protocol, data format, data update rate
  • Transmission distance, cable type, interface hardware
  • System compatibility, electrical isolation, surge protection

Principle

Select the interface from the AWOS architecture, which may be a project-specific wired or digital interface. Verify against the AWOS processor before procurement.

Depends on Sensor Type and System

Consider

  • Supply voltage, current consumption, power source
  • Cable length, voltage drop, protection
  • Earthing/bonding, surge protection, backup power

Remote Installations

Review power availability and cable routing at the system design stage.

Support for Reliable Measurement

Mounting May Include

  • Meteorological mast, instrument pole
  • Dedicated sensor support, equipment platform
  • Existing approved weather-station structure

Separation From

  • Buildings, hangars, trees, lighting structures
  • Exhaust sources, large paved surfaces
  • Other meteorological sensors, aircraft and vehicle areas

Siting on the aerodrome: assess every mast and sensor support against the Annex 14 obstacle limitation surfaces. Equipment on the runway strip or other operational areas must be frangible and mounted as low as its function allows, and may need obstacle marking or lighting under the aerodrome obstacle plan. Agree the location with the aerodrome operator before installation.

Designed for Continuous Outdoor Operation

Selection Should Consider

  • Temperature, humidity, rain, wind, dust
  • Solar radiation, ice or snow where applicable
  • Corrosive environments, electromagnetic conditions

Aggressive Sites

Coastal airports or locations with aggressive conditions may need additional protection.

Transient and Lightning-Related Effects

Consider

  • Surge protection, earthing, bonding
  • Lightning protection of masts and equipment (IEC 62305 series, adopted in India as IS/IEC 62305)
  • Cable shielding, electrical isolation
  • Protective devices, proper cable routing

Coordination

Coordinate the protection arrangement with the airport electrical system and AWOS equipment design.

Follow Manufacturer Instructions and Approved Drawings

ConfirmParameters and approved sensor locations
VerifyMounting structure and installation height
InstallSensor assembly and mechanical fixing
ConnectRoute cables, electrical and communication connections
Power & configureVerify supply, configure interface
CommunicateEstablish link, verify measured values
Verify & documentCalibration or verification checks, commissioning documents

Part of the AWOS Site Design

Sensor-Specific Needs

  • Wind: suitable exposure to prevailing airflow
  • Temperature/humidity: minimal heat and radiation effects
  • Visibility/optical: unobstructed measurement environment

Principle

Establish the final location as part of the AWOS site design, not only for physical convenience.

Accuracy Depends on More Than the Sensor

Activities May Include

  • Calibration verification traceable to national or international measurement standards, functional testing
  • Comparison with reference equipment
  • Cleaning, inspection of sensor surfaces
  • Cable and connector inspection
  • Data-output and system alarm verification

Intervals

Set intervals from manufacturer recommendations, airport maintenance procedures and applicable regulatory requirements.

Confirm Sensor and System Operation

Typical Checks

  • Mechanical installation, orientation, mounting security
  • Power supply, communication interface, sensor identification
  • Data transmission, measurement values, alarm status
  • System display, data recording, calibration or verification status

Acceptance

Accept the sensor only after the required system-level checks are complete.

Regular Maintenance Supports Reliability

Activities

  • Sensor, connector, cable and mounting inspection
  • Cleaning, corrosion inspection
  • Calibration verification, functional and communication testing
  • Power-supply checks, comparison with reference measurements

Frequency

Reflect sensor type, environment, airport operating requirements and manufacturer recommendations.

Typical Problems and Causes

ProblemPossible CausesFirst Action
Sensor data not availableLoss of power, communication failure, cable fault, connector problem, sensor malfunction, AWOS processor fault, configuration errorCheck power and communication path before replacing the sensor
Unstable measurementContamination, environmental interference, loose connection, installation issue, sensor degradation, communication problemCompare with reference information; inspect the complete installation
Incorrect wind directionIncorrect orientation, wrong true or magnetic north reference, magnetic variation not applied, mechanical movement, mounting problem, sensor fault, data configuration errorVerify physical orientation, north reference and system configuration first
Poor visibility measurementOptical contamination, obstruction, condensation, environmental interference, degradation, incorrect locationInspect optical surfaces and installation environment before replacing parts

Check Compatibility With the Existing AWOS

Provide

  • Existing sensor make/model, existing AWOS make/model
  • Measured parameter, communication interface, power supply
  • Existing mounting arrangement, cable details
  • Installation photographs, calibration information where available

Compatibility

Check replacement sensors for mechanical, electrical, communication and software compatibility with the existing AWOS.

Before Requesting an AWOS Sensor, Provide

Sensor Requirements

  • Required measurement parameter
  • Required accuracy, measurement range
  • Communication interface, power supply
  • Mounting arrangement, installation location

Project Information

  • Existing AWOS system details
  • Environmental conditions, cable requirements
  • Calibration requirements, airport authority specification
  • Existing sensor details for replacements
  • A block diagram or existing AWOS datasheet speeds compatibility review

Verify the Applicable Edition

References May Include

  • ICAO Annex 3 (Meteorological Service for International Air Navigation), also published as WMO Technical Regulations, Vol. II
  • ICAO Annex 14 Vol. I, for siting and frangibility of equipment on operational areas
  • ICAO Doc 9837 (Manual on Automatic Meteorological Observing Systems at Aerodromes) and Doc 9328 (Manual of RVR Observing and Reporting Practices)
  • WMO-No. 8 (Guide to Instruments and Methods of Observation)
  • FAA AC 150/5220-16E (Automated Weather Observing Systems for Non-Federal Applications)
  • India Meteorological Department (IMD) and DGCA requirements, airport authority specifications
  • Manufacturer installation and calibration instructions, project AWOS specifications

Principle

Confirm applicable standard editions and local regulatory requirements before procurement.

Sensor Selection as Part of the Complete System

Documentation May Include

  • Sensor datasheet, measurement-range and accuracy information
  • Dimensional drawing, mounting details
  • Electrical and communication interface, cable requirements
  • Installation and maintenance instructions, calibration information
  • Test and commissioning documentation, project compliance documents

Why Precision AGL Solutions

We consider required parameters, measurement performance, existing AWOS compatibility, interface, power, mounting, environment, calibration and airport specifications, so the sensor suits the complete AWOS installation rather than being treated as an isolated device.

AWOS Sensor — Frequently Asked Questions

What is an AWOS sensor?

AWOS (Automated Weather Observing System; ICAO documents call it an automatic meteorological observing system) sensors are measurement devices within the observing system. They give measured inputs to the AWOS processing system, where parameters are monitored, processed, displayed, recorded and made available to associated airport weather and information systems.

Which parameters can AWOS sensors measure?

Typical parameters are wind speed and direction, temperature and relative humidity, atmospheric pressure, visibility, present weather and precipitation, and cloud information and other site-specific parameters. Not every installation needs all of them, so base the selection on the approved system architecture and project requirements.

How should an AWOS sensor be selected?

Begin with the measured parameter, then consider the required range, accuracy and resolution, environmental conditions, response time, data output, communication protocol, power supply, mounting arrangement, cable length, maintenance and calibration requirements, and compatibility with the AWOS processor. Do not select sensors independently of the overall AWOS architecture, because communication, power, data processing and mounting interfaces must operate together.

Where is the wind sensor mounted and how is wind reported?

Wind sensors are normally mounted about 10 m above ground and sited to represent conditions along the runway and at the touchdown zone, with exposure to the wind and no interference from buildings, structures, trees or other obstructions. ICAO Annex 3 uses a 2-minute average for local routine and special reports and ATS displays, and a 10-minute average for METAR and SPECI. Direction is in degrees magnetic in local reports and degrees true in METAR and SPECI, so the sensor north alignment and the magnetic variation entered in the processor must both be correct. Confirm against your current Annex 3 edition.

How are temperature, humidity and pressure sensors positioned and configured?

Temperature and humidity sensors normally sit in a radiation shield, naturally or mechanically aspirated, at about 1.25 to 2 m above ground, away from paved surfaces and exhaust sources, to minimise the influence of direct solar radiation and nearby heat sources. For pressure, QNH and QFE are computed from station pressure, so the barometer elevation and the aerodrome or threshold elevation must be entered correctly. Annex 3 reports both in hectopascals, rounded down to the whole hectopascal.

Can a visibility sensor replace an RVR system?

No. A visibility sensor measures meteorological optical range and is not a substitute for RVR, which is derived from the extinction coefficient, runway light intensity and background luminance (ICAO Doc 9328). Where the runway needs RVR, specify an RVR system. Optical measurement can also be affected by obstructions, local light sources, dust, contamination, precipitation and other environmental conditions.

How do AWOS sensors communicate and how are they powered?

Check the communication protocol, data format, data update rate, transmission distance, cable type, interface hardware, system compatibility, electrical isolation and surge protection, and verify the interface against the AWOS processor before procurement. For power, consider supply voltage, current consumption, power source, cable length, voltage drop, protection, earthing and bonding, surge protection and backup power, and review power availability and cable routing at the system design stage for remote installations.

Where should AWOS masts and sensors be sited on an aerodrome?

Keep sensors separated from buildings, hangars, trees, lighting structures, exhaust sources, large paved surfaces and other meteorological sensors. Assess every mast and sensor support against the Annex 14 obstacle limitation surfaces. Equipment on the runway strip or other operational areas must be frangible and mounted as low as its function allows, and may need obstacle marking or lighting under the aerodrome obstacle plan. Agree the location with the aerodrome operator before installation.

What surge and lightning protection is needed?

Consider surge protection, earthing, bonding, lightning protection of masts and equipment (IEC 62305 series, adopted in India as IS/IEC 62305), cable shielding, electrical isolation, protective devices and proper cable routing. Coordinate the protection arrangement with the airport electrical system and the AWOS equipment design.

How are AWOS sensors calibrated and maintained?

Activities may include calibration verification traceable to national or international measurement standards, functional testing, comparison with reference equipment, cleaning and inspection of sensor surfaces, cable and connector inspection, and data-output and system alarm verification. Set intervals from manufacturer recommendations, airport maintenance procedures and applicable regulatory requirements. At commissioning, accept the sensor only after the required system-level checks are complete.

What are common AWOS sensor problems?

If sensor data is not available, check the power and communication path before replacing the sensor. For unstable measurement, compare with reference information and inspect the complete installation. For incorrect wind direction, verify the physical orientation, the true or magnetic north reference, the magnetic variation and the system configuration first. For poor visibility measurement, inspect optical surfaces and the installation environment before replacing parts.

What information is needed to replace or add an AWOS sensor?

Provide the existing sensor make and model, the existing AWOS make and model, the measured parameter, communication interface, power supply, existing mounting arrangement and cable details, and installation photographs and calibration information where available. Check replacement sensors for mechanical, electrical, communication and software compatibility with the existing AWOS. A block diagram or existing AWOS datasheet speeds the compatibility review.

Which standards apply to AWOS sensors?

References may include ICAO Annex 3 (also published as WMO Technical Regulations, Vol. II), ICAO Annex 14 Vol. I for siting and frangibility of equipment on operational areas, ICAO Doc 9837 and Doc 9328, WMO-No. 8, FAA AC 150/5220-16E, India Meteorological Department (IMD) and DGCA requirements, airport authority specifications, and manufacturer and project AWOS specifications. Confirm the applicable editions and local regulatory requirements before procurement.

Procurement Information for Indian Projects

Indian public tenders commonly ask for the documents below. State which ones your tender requires when you send the enquiry, so they are covered in the quotation.

  • Manufacturer / OEM authorisation
  • Country of origin and local-content declaration (for Make in India purchase preference)
  • Type-test and routine-test certificates, and the FAA / ICAO / IEC compliance documents named in the specification
  • Datasheets, drawings and installation instructions
  • Warranty, delivery period and spares support
  • GeM catalogue or tender-portal requirements, where applicable

Request AWOS Sensor Configuration

Need an AWOS sensor for a new airport weather station, runway weather system or replacement project? Send the required measurement parameter, existing AWOS make/model, required accuracy, measurement range, communication interface, power supply, mounting arrangement and airport specification. We can support sensor compatibility review, technical selection and documentation.

Submitting opens your email client with the enquiry pre-filled. You can also write to precisionaglsolutions@gmail.com or call +91 98214 96412.

Engineering Note

AWOS sensors should be selected and installed as part of the complete airport weather observation system. Accuracy depends on the sensor specification as well as correct siting, mounting, calibration, environmental protection, communications and system configuration.

Confirm exact sensor performance parameters from the selected manufacturer's current technical documentation before procurement.

Product Disclaimer

Product availability, configuration, dimensions, electrical characteristics, photometric performance, certifications and compliance status depend on the selected manufacturer and project specification. The technical values published on this page should not be treated as a substitute for the manufacturer's current approved Technical Data Sheet.

Final selection shall be based on the approved project specification, applicable aviation standards, authority requirements, manufacturer documentation and site conditions. Use of this page is also subject to the Legal Notice, Disclaimer & Terms of Use.

Standards and editions referenced on this site are listed on the Standards Reference page.

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