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Understand the language behind safe ATC communication.

Clear explanations of ICAO language requirements, aviation communication, and the ideas behind effective training — connected to the original sources.

Searches article titles, summaries, topics, and full text across 2 published guides.

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ICAO standards & exams

Requirements, test formats, rating scales, and what official guidance means in practice.

1 guide

icao standards exams · interpretation · September 30, 2026

ICAO English Level 4 for Air Traffic Controllers: What You Need to Demonstrate

Understand ICAO English Level 4, the six assessed skills, how the lowest score affects your result, and what this means for ATC English practice.

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ICAO primary references.

ATCBase explanations are not ICAO publications. Check the original material for exact wording and applicable editions.

ICAO · Language Proficiency RequirementsOfficial LPR overviewScope, related instruments, and official reference links. ICAO · Personnel Licensing FAQLanguage proficiency answersOfficial answers on phraseology, plain language, assessment, and implementation. ICAO Circular 323-AN/185Aviation English training guidelinesGuidance for designing and developing aviation English training programmes. ICAO Doc 9835 · ICAO StoreImplementation manualOfficial catalogue page for the language proficiency implementation manual.