Aviation English
Phonetic Alphabet

四 是什么？

四 The ICAO/FAA radiotelephony spelling for the numeral '4'. Used to clearly communicate headings, altitudes, frequencies, and runway numbers in ATC transmissions.

Source: ICAO Doc 9432, FAA PCG

How is “四” Used in Practice?

下降并保持四千英尺，预计ILS进近跑道一四。

Certification Exam Relevance

ICAO Level 4ICAO Level 5ICAO Level 6EASA FCL.055

Who Needs to Know This Term?

  • Pilots
  • Air Traffic Controllers
  • Cabin Crew

Related Aviation English Terms

千六二三

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Frequently Asked Questions

四 是什么？

The ICAO/FAA radiotelephony spelling for the numeral '4'. Used to clearly communicate headings, altitudes, frequencies, and runway numbers in ATC transmissions.

Where can I learn this term for free?

Termify is a 100% free professional English app that teaches 四 and 4,071+ other industry terms with native pronunciation, IPA transcriptions and career quizzes. Available on iOS in 23 languages. No subscription, no credit card required.

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