AIM
4-2-8. Figures
a. Figures indicating hundreds and thousands in
round number, as for ceiling heights, and upper wind
levels up to 9,900 must be spoken in accordance with
the following.
EXAMPLE-
1. 500 . . . . . . . . five hundred
2. 4,500 . . . . . . four thousand five hundred
b. Numbers above 9,900 must be spoken by
separating the digits preceding the word "thousand."
10/12/17
EXAMPLE-
1. 190 . . . . . . . . Flight Level One Niner Zero
2. 275 . . . . . . . . Flight Level Two Seven Five
4-2-10. Directions
The three digits of bearing, course, heading, or wind
direction should always be magnetic. The word
"true" must be added when it applies.
EXAMPLE-
1. (Magnetic course) 005 . . . . . . zero zero five
2. (True course) 050 . . . . . . . . . . zero five zero true
EXAMPLE-
1. 10,000 . . . . . one zero thousand
3. (Magnetic bearing) 360 . . . . . three six zero
2. 13,500 . . . . . one three thousand five hundred
4. (Magnetic heading) 100 . . . . . heading one zero
zero
c. Transmit airway or jet route numbers as follows.
EXAMPLE-
1. V12 . . . . . . . Victor Twelve
2. J533 . . . . . . . J Five Thirty-Three
d. All other numbers must be transmitted by
pronouncing each digit.
EXAMPLE-
10 . . . . . . . . . . . one zero
e. When a radio frequency contains a decimal
point, the decimal point is spoken as "POINT."
EXAMPLE-
122.1 . . . . . . . . . one two two point one
NOTE-
ICAO procedures require the decimal point be spoken as
"DECIMAL." The FAA will honor such usage by military
aircraft and all other aircraft required to use ICAO
procedures.
5. (Wind direction) 220 . . . . . . . . wind two two zero
4-2-11. Speeds
The separate digits of the speed followed by the word
"KNOTS." Except, controllers may omit the word
"KNOTS" when using speed adjustment procedures;
e.g., "REDUCE/INCREASE SPEED TO TWO
FIVE ZERO."
EXAMPLE-
(Speed) 250 . . . . . . . . . . . . . . . . . two five zero knots
(Speed) 190 . . . . . . . . . . . . . . . . . one niner zero knots
The separate digits of the Mach Number preceded by
"Mach."
EXAMPLE-
(Mach number) 1.5 . . . . . . . . . . . . Mach one point five
(Mach number) 0.64 . . . . . . . . . . . Mach point six four
(Mach number) 0.7 . . . . . . . . . . . . Mach point seven
4-2-9. Altitudes and Flight Levels
4-2-12. Time
a. Up to but not including 18,000 feet MSL, state
the separate digits of the thousands plus the hundreds
if appropriate.
a. FAA uses Coordinated Universal Time (UTC)
for all operations. The word "local" or the time zone
equivalent must be used to denote local when local
time is given during radio and telephone communications. The term "Zulu" may be used to denote UTC.
EXAMPLE-
1. 12,000 . . . . . one two thousand
2. 12,500 . . . . . one two thousand five hundred
b. At and above 18,000 feet MSL (FL 180), state
the words "flight level" followed by the separate
digits of the flight level.
4-2-6
EXAMPLE-
0920 UTC . . . . . zero niner two zero,
zero one two zero pacific or local,
or one twenty AM
Radio Communications Phraseology