Articles

Regulation 9 min

What Is ICAO? The Chicago Convention Explained

How 54 states in 1944 built the rulebook that still governs global aviation. The Chicago Convention, national airspace sovereignty under Article 1, the birth of ICAO and its 193 contracting states, how SARPs and the 19 Annexes work, why IATA is not ICAO, oversight through USOAP, and how states like Saudi Arabia turn the global standard into national law.

Personnel Licensing 12 min

Annex 1: Who Gets to Fly, Control, and Maintain Aircraft

Personnel Licensing is the oldest ICAO Annex and the global baseline for who may fly, control, and maintain aircraft. From the pilot licence ladder and the three medical classes to language proficiency, competency-based training, and how GACA, the FAA, and EASA build national rules on that floor -- a tour of the rulebook for aviation competence.

Flight Operations 10 min

Annex 2: The Rules of the Air Everyone Must Obey

Annex 2 is the rules of the air -- the Standards-only rulebook for who gives way when two aircraft share the sky. Right of way, VFR versus IFR, flight plans, interception, and the one Annex that applies without exception over the high seas under Chicago Convention Article 12, with GACA, the FAA's Part 91, and Europe's SERA built on top.

Flight Operations 10 min

Annex 3: The Weather Intelligence Behind Every Flight

Annex 3 is the weather intelligence behind every flight -- the system, run jointly with the WMO, that turns observations and forecasts into decisions in the cockpit. METARs and TAFs, SIGMET and wind shear warnings, the World Area Forecast System and volcanic ash advisory centres, and how the 2010 Eyjafjallajokull eruption showed what it is for.

Flight Operations 10 min

Annex 4: The Maps Every Pilot Reads the Same Way

Annex 4 makes a chart drawn by any state readable by any pilot in the world. The standardised catalogue of aeronautical charts, the symbology, colour and accuracy specs that make them interoperable, how it relates to Annex 15's underlying data, and why a misread approach chart is a safety risk.

Flight Operations 9 min

Annex 5: Why Altitude Is in Feet but Runways Are in Metres

Annex 5 is the standard for units of measurement in aviation -- SI as the baseline, with feet, nautical miles and knots retained, plus UTC, Celsius and hectopascals. Why the system is a deliberate hybrid, how altimeter settings depend on consistent pressure units, and what the Gimli Glider teaches about getting it wrong.

Flight Operations 9 min

Annex 6: The Rules That Govern How Airlines Operate

Annex 6 governs how aircraft are operated to a common safety standard. The Air Operator Certificate, operational control, flight and duty time limits and FRMS, the MEL, fuel rules and EDTO, recorders and the SMS link to Annex 19 -- and how the FAA's Part 121/135 and EASA's Part-ORO/Part-CAT implement it.

Regulation 9 min

Annex 7: Why Every Aircraft Wears a Nationality

Annex 7 is why every aircraft carries a nationality and registration mark. Rooted in Chicago Convention Articles 17-21: the State of Registry, single registration, ITU-derived prefixes (N, G, HZ, F), the certificate and identification plate, and how leasing and flags of convenience test a system where nationality still fixes responsibility.

Airworthiness 9 min

Annex 8: What Keeps an Aircraft Legal to Fly

Annex 8 is the airworthiness rulebook -- what makes a Certificate of Airworthiness mean the same thing internationally. The chain across States of Design, Manufacture and Registry, the Type Certificate, continuing airworthiness and airworthiness directives, and why a grounded type stays grounded until airworthiness is re-established.