What is 四?
In this glossary, 四 refers to: The ICAO/FAA radiotelephony spelling for the numeral '4'. Used to clearly communicate headings, altitudes, frequencies, and runway numbers in ATC transmissions.
How is 四 used in aviation?
In aviation communication, this term appears in contexts such as: "下降并保持四千英尺,预计ILS进近跑道一四。"
Why does 四 matter in aviation?
四 matters because it supports clear communication in Phonetic Alphabet contexts for Pilots, Air Traffic Controllers, and Cabin Crew. It also connects to aviation training and exam language such as ICAO Level 4, ICAO Level 5, ICAO Level 6, and EASA FCL.055.
Who uses 四?
四 is mainly used by Pilots, Air Traffic Controllers, and Cabin Crew.
What category does 四 belong to?
In this glossary, 四 is grouped under Phonetic Alphabet. Related pages in this category explain adjacent procedures, commands and operational concepts.
Where does this definition come from?
This definition is sourced from ICAO Doc 9432, FAA PCG and published by Protermify Aviation as a static aviation reference page.