Automatic Terminal Information Service (ATIS)

Feature Desk, Aviation Gurukul, GOLN

4 years ago

The Automatic Terminal Information Service (ATIS) is a critical component of air traffic control communications. ATIS provides pilots with up-to-date information about weather conditions, runway conditions, and other important information related to the operation of an airport. ATIS messages are pre-recorded and broadcast on a loop, and pilots are required to listen to the message before they can request clearance for takeoff or landing. The information provided by ATIS helps pilots make informed decisions about how to operate their aircraft safely and also helps air traffic controllers manage traffic flow more efficiently.

ATIS messages are updated regularly based on changing conditions, and the system is designed to provide accurate and timely information to pilots to ensure safe and efficient operations at airports around the world.

Automatic Terminal Information Service (ATIS)

Before the introduction of ATIS, pilots relied on direct voice communication with air traffic controllers or weather services for airport-specific information. This manual process was time-consuming, prone to errors, and led to congested communication channels. Recognizing the importance of providing pilots with streamlined and accurate information, aviation authorities introduced ATIS as a solution.

Definition

The automatic provision of current, routine information to arriving and departing aircraft throughout 24 hrs or a specified portion thereof:

Data link-automatic terminal information service (D-ATIS). The provision of ATIS via data link.

Voice-automatic terminal information service (Voice-ATIS). The provision of ATIS using continued and repetitive voice broadcasts.

(ICAO Doc 4444: PANS-ATM)

Content of Voice-ATIS Broadcasts

Voice-ATIS broadcasts normally contain the following information in the order listed:

name of the aerodrome;
arrival and/or departure indicator;
contract-type, if communication is via D-ATIS;
designator;
time of observation, if appropriate;
type of approach(es) to be expected;
the runway(s) in use; the status of the arresting system constituting a potential hazard, if any;
significant runway surface conditions and, if appropriate, braking action;
holding delay, if appropriate;
transition level, if applicable;
other essential operational information;
surface wind direction (in degrees magnetic) and speed, including significant variations, and, if surface wind sensors related specifically to the sections of the runway(s) in use are available and the information is required by operators, the indication of the runway and the section of the runway to which the information refers;
visibility and, when applicable, RVR;
present weather;
cloud below 1 500 m (5 000 ft) or below the highest minimum sector altitude, whichever is greater; cumulonimbus; if the sky is obscured, vertical visibility when available;
air temperature;
dew point temperature;
altimeter setting(s);
any available information on significant meteorological phenomena in the approach and climb-out areas including wind shear, and information on recent weather of operational significance;
trend forecast, when available; and
specific ATIS instructions.

Voice ATIS may be transmitted on a dedicated VHF communications frequency or as the voice element of a navigational facility (e.g. VOR).

At busy airports, separate ATIS broadcasts may be made for arrivals and departures.

Use of ATIS

An important element of an ATIS broadcast is the designator (identifying code), which is a letter of the ICAO spelling alphabet. Designators assigned to consecutive ATIS are in alphabetical order. The pilot listens to the ATIS just before initial contact and notes the code letter; on check-in, the pilot reports the code letter of the ATIS copied. This enables the controller to confirm that the pilot has copied the current ATIS. Normal practice is for the controller to update the pilot if the ATIS or any element of it subsequently changes materially.

In some cases, Operator procedures predicated on R/T communications safety require that both pilots in multi-crew aircraft remain on the principal ATC frequency once the aircraft is below FL100/10,000ft. This means that ATC must pass any significant changes to the reported ATIS.

Components of an ATIS Message

An ATIS message typically includes the following components:

Identifier: Every ATIS message starts with a phonetic letter, beginning with “Alpha” and progressing sequentially (e.g., Bravo, Charlie, etc.). This letter changes with every update to ensure pilots are referencing the most current information.
Weather Information: This section relays details about current weather conditions, including temperature, dew point, wind direction and speed, visibility, cloud cover, and barometric pressure. Any special weather phenomena like thunderstorms, fog, or icing are also mentioned.
Runway Information: Active runways for both landings and takeoffs are specified. Additionally, any pertinent information about runway conditions (like wet runways or construction) is provided.
Notices to Airmen (NOTAMs): Crucial notifications about airport operations, temporary changes, or hazards are shared in this section. For example, if a taxiway is closed for repairs, it would be mentioned here.
Special Instructions: Occasionally, special instructions or reminders might be included, such as noise abatement procedures or specific taxiing instructions.
End of Message: The broadcast concludes by reiterating the phonetic letter identifier and asking pilots to mention they have received the specific ATIS information upon initial contact with the tower.

Benefits of ATIS

Efficiency: With ATIS, pilots can receive all essential information in a structured and predictable manner without having to engage in extended communication with air traffic controllers.
Safety: By providing up-to-date and consistent information, ATIS ensures that pilots are aware of current conditions and any potential hazards, allowing for safer flight operations.
Reduced Communication Load: Air traffic controllers no longer need to repeat the same information continuously to different pilots, freeing up communication channels and reducing the chance of misunderstandings.

Digital Evolution: D-ATIS

With technological advancements, ATIS has evolved into D-ATIS (Digital ATIS). Instead of solely being an audio broadcast, D-ATIS delivers text-based information to aircraft equipped with compatible systems. This transition provides a few advantages:

Clarity: Text-based information can be easier to understand and reference, eliminating potential confusion from misheard details.
Integration: Many modern avionic systems can integrate D-ATIS information directly, allowing for enhanced flight planning and situational awareness.
Flexibility: D-ATIS can be updated more rapidly and can contain more detailed information without burdening the listener with lengthy audio broadcasts.

International Variation

While the core purpose of ATIS remains consistent worldwide, there can be slight variations in format or content based on regional preferences or regulations. Pilots operating internationally should be aware of these potential differences and ensure they understand the local ATIS format.

Future of ATIS

As aviation technology continues to advance, so will the systems supporting it. Potential future enhancements to ATIS could include:

Visual ATIS: Incorporating graphical representations of weather conditions, runways, and other data to provide an even more comprehensive understanding for pilots.
Personalized ATIS: Leveraging AI and advanced avionic systems, ATIS messages could be tailored to individual aircraft, providing only the most relevant information.
Real-time Updates: With advancements in real-time data processing, ATIS could provide dynamic, constantly updated information to pilots, reflecting changes as they happen.

The Automatic Terminal Information Service (ATIS) is a testament to the aviation industry’s commitment to safety, efficiency, and continuous improvement. By ensuring that pilots and air traffic controllers have access to the most recent and relevant airport information, ATIS plays a pivotal role in maintaining the smooth operation of air traffic around the world.

As technology continues to evolve, it’s exciting to imagine how services like ATIS will adapt and innovate, ensuring that the skies remain a place of wonder, exploration, and, above all, safety.