Part 3.
Air-ground communications
July 1917
TELS P 09
COMMUNICATION METHODS
Air-Ground Communication (Definition)
two-way communication between aircraft and stations or
locations on the surface of the earth
Radiotelephony
communication by means of radio waves rather than by
transmitting along wires or cables
SELCAL
selective-calling radio system that can alert an aircraft's crew
that a ground radio station wishes to communicate with the
aircraft.
Controller-Pilot Data Link Communications (CPDLC)
means of communication between controller and pilot, using
data link for ATC communications.
General Requirements
Radiotelephony and/or data link shall be used in air-ground
communications for air traffic services purposes.
ATS units to be provided with and to maintain guard on
the emergency channel 121.5 MHz
When direct pilot-controller two-way radiotelephony
or data link communications are used for the
provision of air traffic control service, recording facilities shall
be provided on all such air-ground communication channels.
Recordings shall be retained for a period of at least thirty days.
Radiotelephony Procedures
GENERAL
Word Spelling in Radiotelephony:
when proper names, service abbreviations and words
of which the spelling is doubtful are spelled out in
radiotelephony the ICAO Radiotelephony Spelling
Alphabet shall be used
RADIOTELEPHONY
SPELLING
ALPHABET
Radiotelephony Procedures
RADIOTELEPHONY SPELLING ALPHABET
Exercise:
Give the approximate pronunciation of the following:
GALIM
ZANIG
YSTEC
9VDHU
JZYTY
OORWB
FXLQKV
PRONUNCIATION OF NUMBERS
When English Language is used, numbers shall be
transmitted using following pronunciation:
NUMERAL or NUMERAL
ELEMENT
0
PRONUNCIATION
ZE-RO
1
WUN
2
TOO
3
TREE
4
FOW-er
5
FIFE
6
SIX
7
SEV-en
8
AIT
9
Decimal
Hundred
Thousand
NIN-er
DAY-SEE-MAL
HUN-dred
TOU-SAND
Radiotelephony Procedures
TRANSMISSION OF NUMBERS

All numbers shall be transmitted by pronouncing each digit
separately
examples:
aircraft callsigns
transmitted as
TGZ 238
Zena two three eight
BRU 242
Belavia two four two
BMA 600
Midland six zero zero
THY 001
Turkish zero zero one
Radiotelephony Procedures
TRANSMISSION OF NUMBERS

All numbers shall be transmitted by pronouncing each digit
separately
examples:
flight levels
transmitted as
FL 180
flight level one eight zero
FL 200
flight level two zero zero
FL 135
flight level one three five
FL 80
flight level eight zero
Radiotelephony Procedures
TRANSMISSION OF NUMBERS

All numbers shall be transmitted by pronouncing each digit
separately
examples:
wind direction & speed
transmitted as
200 degrees 70 knots
wind two zero zero degrees
seven zero knots
160 degrees 18 knots
gusting 30 knots
wind one six zero degrees one
eight knots gusting three zero
Radiotelephony Procedures
TRANSMISSION OF NUMBERS
ALL numbers used in transmission of ALTITUDE, CLOUD
HEIGHT, VISIBILITY & RUNWAY VISUAL RANGE information
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
Radiotelephony Procedures
TRANSMISSION OF NUMBERS

Hundred, thousand & combination of thousand & hundred
examples:
number
transmitted as
10
one zero
75
seven five
100
one hundred
583
five eight three
2 500
two thousand five hundred
Radiotelephony Procedures
TRANSMISSION OF NUMBERS

Hundred, thousand & combination of thousand & hundred
examples:
number
transmitted as
5 000
five thousand
11 000
one one thousand
25 000
two five thousand
38 143
three eight one four
three
Radiotelephony Procedures
TRANSMISSION OF NUMBERS

Hundred, thousand & combination of thousand & hundred
examples:
altitude
transmitted as
800
eight hundred
3 400
three thousand four hundred
12 000
one two thousand
Radiotelephony Procedures
VERIFICATION OF NUMBERS
When accuracy of reception of numbers needs to be verified,
the person transmitting shall request the person receiving to
read back the numbers
Radiotelephony Procedures
TRANSMISSION OF TIME
Only the minutes of the hour are normally required. Each digit
should be pronounced separately. Hour included if possibility
of confusion.
examples:
time
statement
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
1300 (1:00 p.m.)
WUN TREE ZE-RO ZE-RO
Note: Co-ordinated Universal Time (UTC) shall be used
Radiotelephony Procedures
STANDARD WORDS & PHRASES
Word/Phrase
Meaning
ACKNOWLEDGE
Let me know that you have received and
understood this message
AFFIRM
Yes
APPROVED
Permission for proposed action granted
CANCEL
Annul the previously transmitted clearance
CHECK
Examine a system or procedure. (No answer is
normally expected)
Radiotelephony Procedures
STANDARD WORDS & PHRASES
Word/Phrase
Meaning
CONFIRM
Have I correctly received the following…? or Did you
correctly receive this message?
CONTACT
Establish radio contact with…
CORRECT
That is correct
CORRECTION
An error has been made in this transmission (or
message indicated). The correct version is …
DISREGARD
Consider that transmission as not sent
Radiotelephony Procedures
STANDARD WORDS & PHRASES
Word/Phrase
Meaning
GO AHEAD
Proceed with your message
Note- not
normally used in surface movement communications
HOW DO YOU READ
What is the readability of my transmission?
I SAY AGAIN
I repeat for clarity and emphasis
NEGATIVE
No or Permission not granted or That is not correct
REQUEST
I should like to know … or I wish to obtain …
Radiotelephony Procedures
STANDARD WORDS & PHRASES
Word/Phrase
Meaning
OVER
My transmission is ended and I expect a response from
you
Note- not normally used in VHF
comms.
READ BACK
Repeat all, or specified part, of this message back to
me exactly as received
REPORT
Pass me the following information
REQUEST
I should like to know … or I wish to obtain …
Radiotelephony Procedures
STANDARD WORDS & PHRASES
Word/Phrase
Meaning
ROGER
I have received all of your last transmission Note- not to
be used in reply to a question requiring readback or a
direct answer in the AFFIRM or NEGATIVE
SAY AGAIN
Repeat all, or the following part, of your last
transmission
SPEAK SLOWER
Reduce your rate of speech
STANDBY
Wait and I will call you
VERIFY
Check and confirm with originator
Radiotelephony Procedures
STANDARD WORDS & PHRASES
Word/Phrase
Meaning
WILCO
(Abbreviation for ‘will comply’) I understand your
message and will comply with it
WORDS TWICE
a) As a request:
Communication is difficult. Please
send every word or group of words
twice
b) As information:
Since communication is difficult, every
word or group of words in this
message will be sent twice
Questions…