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07. Transmission of numbers in radiotelephony

Wikis > Communications > 07. Transmission of numbers in radiotelephony
5.2.1.4 Transmission of numbers in radiotelephony

5.2.1.4.1 Transmission of numbers

5.2.1.4.1.1 All numbers, except as prescribed in 5.2.1.4.1.2, shall be transmitted by pronouncing each digit separately.Note.

    The following examples illustrate the application of this procedure (see 5.2.1.4.3.1 for pronunciation).
aircraft call signstransmitted as
CCA 238Air China two three eight
OAL 242Olympic two four two
flight levelstransmitted as
FL 180FL 200
flight level one eight zeroflight level two zero zero
headingstransmitted as
100 degreesheading one zero zero
080 degreesheading zero eight zero
wind direction and speedtransmitted as
200 degrees 70 knotswind two zero zero degrees seven zero knots
160 degrees 18 knots gusting 30 knotswind one six zero degrees one eight knots gusting three zero knots
transponder codestransmitted as
2 400squawk two four zero zero
4 203squawk four two zero three
runway/th>transmitted as
27runway two seven
30runway three zero
altimeter settingtransmitted as
1 010QNH one zero one zero
1 000QNH one zero zero zero
5.2.1.4.1.2 All numbers used in the transmission of altitude, cloud height, visibility and runway visual range (RVR) information, which contain whole hundreds and whole thousands, shall be transmitted by pronouncing each digit in the number of hundreds or thousands followed by the word HUNDRED or THOUSAND as appropriate. Combinations of thousands and whole hundreds shall be transmitted by pronouncing each digit in the number of thousands followed by the word THOUSAND followed by the number of hundreds followed by the word HUNDRED.Note.

    • The following examples illustrate the application of this procedure. See

5.2.1.4.3.1 (Pronunciation of numbers)

    for pronunciation).
altitudetransmitted as
800eight hundred
3 400three thousand four hundred
12 000one two thousand
cloud heighttransmitted as
2 200two thousand two hundred
4 300four thousand three hundred
visibilitytransmitted as
1 000visibility one thousand
700visibility seven hundred
runway visual rangetransmitted as
600RVR six hundred
1 700RVR one thousand
seven hundred
5.2.1.4.1.3 Numbers containing a decimal point shall be transmitted as prescribed in 5.2.1.4.1.1 with the decimal point in appropriate sequence being indicated by the word DECIMAL.Note 1.

    The following examples illustrate the application of this procedure:
NumberTransmitted as
100.3ONE ZERO ZERO DECIMAL THREE
38 143.9THREE EIGHT ONE FOUR THREE DECIMAL NINE

Note 2.

    • For identification of VHF frequencies the number of digits used after the decimal point are determined on the basis of the channel spacing (

5.2.1.7.3.4.3

    • refers to frequencies separated by 25 kHz,

5.2.1.7.3.4.4

    • refers to frequencies separated by 8.33 kHz).

Note 3.

    The channelling/frequency pairing relationship for 8.33 kHz and 25 kHz is found in Table 4-1 (bis), Volume V.
5.2.1.4.1.4 PANS. When transmitting time, only the minutes of the hour should normally be required. Each digit should be pronounced separately. However, the hour should be included when any possibility of confusion is likely to result.Note.

    The following example illustrates the application of this procedure when applying the provisions of 5.2.1.2.2:
TimeStatement
0920 (9:20 A.M.)TOO ZE-RO or
ZE-RO NIN-er TOO ZE-RO
1643 (4:43 P.M.)FOW-er TREE or
WUN SIX FOW-er TREE
5.2.1.4.2 Verification of numbers5.2.1.4.2.1

When it is desired to verify the accurate reception of numbers the person transmitting the message shall request the person receiving the message to read back the numbers.

5.2.1.4.3 Pronunciation of numbers

When the provisions of 5.2.1.2.2 (see below) are applied, numbers shall be transmitted using the following pronunciation:

Numeral or numeral elementPronunciation
0ZE-RO
1WUN
2TOO
3TREE
4FOW-er
5FIFE
6SIX
7SEV-en
8AIT
9NIN-er
DecimalDAY-SEE-MAL
HundredHUN-dred
ThousandTOU-SAND

Note.

    The syllables printed in capital letters in the above list are to be stressed; for example, the two syllables in ZE-RO are given equal emphasis, whereas the first syllable of FOW-er is given primary emphasis.

Source: ICAO Annex 10.2

 
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