How often are ATIS broadcasts updated?

ATIS, or Automatic Terminal Information Service, is designed to provide essential information to pilots about current weather conditions, active runways, and other pertinent details for arriving and departing flights.

The correct answer relates to the mechanism by which ATIS updates are triggered. Broadcasts are updated upon the receipt of any official weather report. This means that if there is a change in the weather conditions that is documented through an official measurement, such as a new METAR (Meteorological Aerodrome Report), an ATIS broadcast will be generated to inform pilots of this change. This makes the information relayed via ATIS current and relevant, enhancing safety through timely updates.

In contrast, the other options suggest more rigid scheduling of updates, which doesn't reflect the operational nature of ATIS. For example, updating every 30 minutes or only during significant weather changes could lead to pilots operating with potentially outdated or misleading information. While updates on the hour might seem systematic, they do not account for the variability of weather changes that can impact flight planning and safety.