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10.5.1: ALS and FIS

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    78383
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    Alerting service (ALS) can be defined as [ICAO Annex. 11]:

    a service provided to notify appropriate organizations regarding aircraft in need of search and rescue aid, and assist such organizations as required.

    In other words, it is a protocol established to deploy all necessary resources for search and rescue in case of any situation of emergency notified by the crew of the aircraft. Indeed, there is an emergency code (squawk 7700 code) that pilots must tune in the transponder to notify an emergency.

    The Flying Information Service (FIS) can be defined as [ICAO Annex. 11]:

    Flight information service is a service provided for the purpose of giving advice and information useful for the safe and efficient conduct of flights.


    10.5.1: ALS and FIS is shared under a CC BY-SA 3.0 license and was authored, remixed, and/or curated by Manuel Soler Arnedo via source content that was edited to conform to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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