Pronunciation of numbers used flight operations is very important.  To avoid confusion, the ICAO phonetic numbers are used.  Numbers are particularly important for flight levels, headings, speeds, fuel quantities and weather information.  

NOTE: Sometimes Flight Levels are used to express altitudes, e.g. 33,000 is Flight Level 330.  Due to international differences some countries use different Flight Level Notation.  For example in the US Flight Levels start at 18,000 feet.

Read and memorise all of the ICAO phonetic numbers.  To increase intelligibility it is good to say them slowly and clearly.

NUMBER   PRONUNCIATION

0  Zero     Ze ro

1 One       Wun

2 Two       Too

3 Three     Tree

4 Four       Fow er

5 Five        Fife

6 Six         Six

7 Seven     Sev en

8 Eight      Ate

9 Nine       Nin er

10 Ten      Ten

Hundred    Hundred

Thousand  Tau sand

Exercise:

1. Spell your phone number using the ICAO phonetic alphabet.
2. Look at the flight levels below.  How would you pronounce them?
3. Try the exercise again, but this time pretend to be a controller and say "climb and maintain" before each altitude.

4200

9000  

12500

16000

27000

33000   

When you are confident using the ICAO number system, start the next lesson, which is about listening to ATIS.