Introduction and essential definitions; AIP, NOTAM, AIRAC and AIC.
This topic is ICAO-framework material — the content below is a study aid, not cited regulation. Always verify against the current ICAO documents and national AIP.
The Aeronautical Information Service (AIS) is the system responsible for collecting, collating, and distributing aeronautical information necessary for the safety, regularity, and efficiency of air navigation. ICAO Annex 15 establishes the standards and recommended practices governing AIS worldwide. Every contracting state is required to provide an AIS covering its territory.
The core function of AIS is to ensure that accurate, timely, and consistent information reaches pilots, operators, and air traffic services before and during flight. Without a reliable information chain, operations in controlled and uncontrolled airspace would be impractical and unsafe.
The AIP is the primary document through which a state publishes permanent aeronautical information essential to air navigation. It is divided into three parts:
The AIP is a living document. Amendments are issued at regular intervals and must be incorporated promptly. Pilots operating in an unfamiliar state should consult that state's AIP before flight — procedures, frequencies, and requirements can differ significantly.
A NOTAM is a notice distributed by means of telecommunication containing information concerning the establishment, condition, or change in any aeronautical facility, service, procedure, or hazard, where timely knowledge is essential to personnel concerned with flight operations.
NOTAMs cover short-duration or unpredictable changes: temporary airspace restrictions, navigational aid outages, obstacle warnings, unlighted cranes, military exercises, and similar items. They are identified by a series letter and serial number, and must be checked for every planned flight via an official NOTAM retrieval system. A flight planned without checking NOTAMs is an incomplete flight plan.
The AIRAC system is a globally standardised cycle of 28 days used to coordinate the publication and simultaneous implementation of significant operational changes — procedure amendments, airspace restructuring, frequency reassignments, and route modifications. Because every state adheres to the same fixed calendar, the entire aviation system updates at the same moment.
For PPL students the practical consequence is straightforward: aerodrome charts and instrument procedure plates in electronic flight bags carry an AIRAC effective date. One cycle out of date means your data is 28 days old and may reflect procedures no longer in force.
An AIC carries information that does not qualify for a NOTAM or AIP amendment but is nonetheless operationally useful — administrative changes, safety notices, advance notification of future AIP amendments, and explanatory or educational material. AICs are not operationally binding in the same sense as AIP content, but they convey guidance that pilots are expected to read.
Together the AIP, NOTAM system, AIRAC cycle, and AICs form the complete aeronautical information chain. A pilot who consults all four elements before departure has fulfilled the pre-flight information obligation that underpins safe flight planning.
This block connects to your school's own Operations Manual (OM-A/B/C/D). In the full product it shows, cited to your manual, how YOUR organisation implements the regulation above — private to your school. (Demo placeholder.)
The following items are labeled illustrative context only — they are not regulation and do not replace pre-flight NOTAM checking against official sources.
Three active FAA Temporary Flight Restrictions (TFRs) in the US Pacific Northwest illustrate the NOTAM system in practice. TFRs are published as NOTAMs and represent time-critical changes to airspace status that pilots must identify before every flight:
Moses Lake, WA CASE-1: Hazard TFR 19 NM south of Moses Lake (NOTAM 6/6571), effective 18–31 July 2026, managed by Seattle Center (ZSE). A cross-country VFR flight transiting central Washington without a pre-flight NOTAM check could enter this restricted volume without any awareness.
Kennewick, WA CASE-2: Hazard TFR 48 NM northeast of Kennewick (NOTAM 6/6568), same period, same managing facility (ZSE). The geographical spread between this TFR and the Moses Lake example — both within one ARTCC — illustrates how a single ATS unit can hold multiple simultaneous NOTAMs across a large area.
Pendleton, OR CASE-3: Hazard TFR 24 NM east of Pendleton (NOTAM 6/6564), same period, also ZSE. Oregon falls within the Seattle FIR, confirming that NOTAM management follows FIR boundaries rather than state borders — a distinction directly relevant to cross-border flight planning.
All three were issued on the same date (18 July 2026), consistent with a coordinated hazard-management operation. The operational takeaway: a NOTAM check covering only the departure aerodrome and its immediate vicinity would miss all three. Pre-flight briefings must cover the full planned route plus applicable alternates.
1. What is the length of one AIRAC cycle?
The lesson defines the AIRAC system as a globally standardised cycle of 28 days used to coordinate the simultaneous publication and implementation of significant operational changes across all states.
2. Which part of the AIP contains individual aerodrome data such as runway dimensions and radio frequencies?
The lesson specifies that the AD part covers individual aerodrome data — runway dimensions, frequencies, charts, and handling facilities — as distinct from the ENR and GEN parts.
3. What is the operational status of an Aeronautical Information Circular (AIC)?
The lesson explicitly states that AICs are not operationally binding in the same sense as AIP content, though they convey guidance pilots are expected to read.
4. Which type of information would correctly be published as a NOTAM rather than an AIC?
The lesson lists navigational aid outages as a NOTAM subject, while advance AIP amendment notifications and administrative or educational material are explicitly named as AIC content.
5. What obligation does ICAO Annex 15 place on contracting states regarding aeronautical information?
The lesson states that ICAO Annex 15 establishes worldwide AIS standards and that every contracting state is required to provide an AIS covering its territory.