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Automatic Terminal Information Service

by Admin on November 7, 2022

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Airports with a high level of traffic can utilize Automatic Terminal Information Services (ATIS) to archive aeronautical data continuously. The ATIS system today has made pilots’ and air traffic controllers’ lives easier since they must deal with a great deal of information. Before every flight, iJET checks the necessary NOTAM and ATIS information in order to perform pre-flight operations safely.

Airports and their immediate surroundings are equipped with automatic terminal information services (ATIS), which broadcast continuous aeronautical information. An airport’s ATIS broadcast contains important information about weather, runways, approaches, and anything else pilots need, such as important NOTAMs. ATIS broadcasts are usually listened to by pilots before contacting a local control unit. This lessens controllers’ workload and alleviates frequency congestion.

In a 24-hour period or a specified portion thereof, the following information is provided automatically to arriving and departing aircraft:

Automatic terminal information service for data links (Data link-automatic terminal information service). Through data links, ATIS can be provided.
A voice-activated terminal information service (Voice-ATIS Broadcasts). Voice broadcasts provide ATIS in a continuous and repetitive manner.

ATIS In Aviation

Designators, which are letters of the ICAO alphabet, are important elements of ATIS broadcasts. In alphabetical order, ATIS designations are assigned to consecutive ATIS. In the days prior to initial contact, the pilot listens to the ATIS and notes its code letter; upon check-in, and reports the ATIS code letter. Pilots are required to copy the current ATIS in order to confirm that the controller has copied it correctly. If an element of the ATIS or the ATIS itself changes materially, it is normal for the controller to update the pilot.

Some operators require that, once an aircraft has reached FL100/10,000ft, both pilots remain on the principal ATC frequency in accordance with R/T communications safety procedures. In other words, ATIS must be updated whenever there are significant changes.

Voice-ATIS Broadcasts

These are the information that is usually broadcast in the order listed in Voice-ATIS broadcasts:

The name of the aerodrome
Indicator of arrival and/or departure
In the case of D-ATIS communication, contract type
Date and time of observation, if applicable
Approach type(s) to be anticipated
Observe runway surface conditions and apply brakes if necessary
In the event of a holding delay
When surface wind sensors are available for specific sections of runway(s) in use, the direction and speed of the wind on those sections and, if the information is required by operators, the runway name and section of the runway
Whenever possible, visibility and RVR should be considered
Current Weather conditions
Temperature of the air
The temperature at which dew points form
Setup of the altimeter
In case there are important meteorological phenomena present in the approach and climb-out areas including wind shear, or if there have been any significant changes in the weather in recent months.

AWIS (Aerodrome Weather Information Service)

The AWIS provides ATC operators, particularly pilots, with current (one minute) weather conditions, including surface wind, pressure, air temperature, dew point temperature, rainfall, cloud information, humidity, and visibility. Prior to approach to the aerodrome or during flight planning, these can be used. As a result of weather observations, the following can be accomplished:

Prior to becoming visually aware of the aerodrome, pilots use wind information to decide which runway approach to take
Wet runways indicate braking distances for rain
Altimeter (QNH) settings are based on pressure (QNH) and allow lower approaches (Approach with Vertical Guide (APV))
Cloud cover and visibility allow the pilots to determine whether current conditions are meeting (or exceeding) required minimums
In the absence of ceiling meters or visibility sensors, dewpoint and humidity can indicate fog, mist, or low cloud
Approach and takeoff calculations are based on temperature.

Automated Weather Observing System (AWOS)

Airport weather information and reports are continuously updated and reported by Automated Weather Observing System (AWOS). Aircraft service providers operate, maintain, and control most AWOS stations. A combination of these parameters may be measured by AWOS depending on the configuration:

Setting the altimeter for barometric pressure and density
Dew point and temperature
Visibility and visibility variability
The condition of the sky, the height of the clouds, and the accumulation of liquid precipitation
Rain, snow, or drizzle (e.g.) type of precipitation identification
An instrument for detecting lightning from clouds to ground can be used to detect thunderstorms
Detection of freezing rain (using a freezing rain sensor)
Conditions of the runway surface.

ASOS (Automated Surface Observing System)

Generally, US automated weather stations are called Automated Surface Observing Systems (ASOS). Though it shares some similarities with AWOS, it is more sophisticated and provides a wealth of information for making weather forecasts. Among U.S. climatology observing networks, it serves as the country’s primary network.

In contrast to AWOS, ASOS provides additional information on the type and intensity of precipitation (rain, snow, freezing rain) and obstructions to visibility (fog and haze). AWOS typically includes ceiling and sky conditions, visibility, temperature, dew point, altimeter setting, and wind speed, gusts and direction. Besides wind shifts and peak winds, ASOS can also track rapid pressure changes and precipitation accumulations.

In general, these systems send hourly reports, but they can also issue special observation reports if the weather conditions rapidly change and cross specific thresholds. Usually, the automated observations are edited or enhanced by human observers by air traffic controller.

The Role of iJET In the Information Service

Information on current weather conditions, runway activity, available approaches, as well as important NOTAMs can be found in ATIS broadcasts. In the case of non-control airport/terminal areas and meteorological information, iJET provides aircraft with advance non control information using ATIS.