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8. COM - 5.0 RADIO COMMUNICATIONS

COM - 5.0 RADIO COMMUNICATIONS

• 5.1 General
• 5.2 Language
• 5.3 VHF Communication Frequencies– Channel Spacing
• 5.4 Use of Phonetics
• 5.5 Airways and Air Routes Designation
• 5.6 Distance Reporting
• 5.7 Use of Numbers
• 5.8 Call Signs
  • 5.8.1 Civil Aircraft
  • 5.8.2 Ground Stations
  • 5.8.3 RCO
• 5.9 Standard Radio Telephony
• 5.10 Communications Checks
• 5.11 Emergency Communications
• 5.12 Monitoring of Emergency Frequency 121.5 MHz
• 5.13 VHF Frequency Allocations
  • 5.13.1 Air Traffic Services
  • 5.13.2 Soaring
  • 5.13.3 Air-to-Air
• 5.14 Use of Frequency 5680 kHz
• 5.15 Phone Use During a Radio Communications Failure

5.1 General

This part deals with radio communications between aircraft and ground stations. Particular emphasis is placed on radiotelephony procedures that are intended to promote understanding of messages and reduce communications time.

The primary medium for aeronautical communications in Canada is VHF-AM in the frequency range of 118 to 137 MHz. For increased range in the northern areas and the North Atlantic, HF-SSB is available in the frequency range of 2.8 to 22 MHz.

Regulations

Operator’s Certificates: In accordance with the Radiocommunication Regulations, a person may operate radio apparatus in the aeronautical service only where the person holds a Restricted Operator Certificate with Aeronautical Qualification, issued by Industry Canada.

Station Licences: All radio equipment used in aeronautical services required to be licensed by Industry Canada.

For complete information on the requirements for communication in Canada, please consult the Study Guide for the Radiotelephone Operator’s Restricted Certificate Aeronautical, (RIC21). This study guide is available from the nearest Industry Canada district office or by calling (613) 998-4149.

5.2 Language

The use of English and French for aeronautical radio communications in Canada is detailed in sections 602.133, 602.134, and 602.135 of the CARs. The regulations specify that air traffic services shall be provided in English and sets out the locations where services shall be provided in French as well. The tables containing the names of those locations, as well as the pertinent section of the CARs are contained in COM Annex A.

For safety and operational efficiency, once the language to be used has been determined, the pilot should refrain from changing language in the course of communications without formal notification to that effect. In addition, pilots should endeavour to become thoroughly familiar with the aeronautical phraseology and terminology applicable to the type of service being provided in the official language of their choice.

5.3 VHF Communication Frequencies– Channel Spacing

The standard VHF A/G channel spacing in Canada is 25 kHz. A 760 channel transceiver is necessary for operation of 25 kHz channels. In some areas of Europe, channel spacing has been reduced to 8.33 kHz.

This channel spacing means that some operators with 50 kHz capability will have their access to certain Canadian airspace and airports restricted as 25 kHz channels are implemented for ATC purposes. Similarly, where ATC makes use of 8.33 kHz channels in Europe, restrictions may also apply.

Because the frequency selectors on some 25 kHz transceivers do not display the third decimal place, misunderstanding may exist in the selection of frequencies. With such transceivers, if the last digit displayed includes 2 and 7, then the equipment is capable of 25 kHz operations.

Example:

Toronto Centre: 132.475 (actual frequency)
ATC Assigned Frequency: 132.47 (digit 5 omitted)
Aircraft Radio Display: 132.475 or 132.47

In either case, the aircraft radio is actually tuned to the proper frequency.

5.4 Use of Phonetics

Phonetic letter equivalents shall be used for single letters or to spell out groups of letters or words as much as practicable. The ICAO phonetic alphabet should be used.

When spoken, capitalized syllables are given equal stress, e.g., ECKS-RAY. When only one syllable is capitalized, that syllable is given primary stress, e.g., NINE-er.

5.5 Airways and Air Routes Designation

Phonetics are used with the designation of Canadian airways and air routes.

Examples:

	WRITTEN	SPOKEN
AIRWAYS	G1	GOLF1
	A2	ALFA 2
	J500	JET 500
AIR ROUTES	RR3	ROMEO ROMEO 3
	BR4	BRAVO ROMEO 4

5.6 Distance Reporting

Distance reporting based on RNAV and GPS will be provided in miles, e.g. 30 mi. from Someplace. When distance reports are based on DME, pilots will state DME, e.g. 30 DME from Someplace.

5.7 Use of Numbers

All numbers except whole thousands should be transmitted by pronouncing each digit separately:

Examples:

572	FIVE SEVEN TWO
11000	ONE ONE THOUSAND

Altitude above sea level is expressed in thousands and hundreds of feet. Separate digits must be used to express flight levels.

Examples:

2700	TWO THOUSAND SEVEN HUNDRED
FL260	Flight Level TWO SIX ZERO

Aircraft type numbers, wind speed and cloud base may be expressed in group form:

Examples:

DC10	DC TEN
Wind 270/10	WIND TWO SEVEN ZERO AT TEN
3400 broken	THREE THOUSAND FOUR HUNDRED BROKEN

Time – Co-ordinated Universal Time (UTC)

Examples:

0920Z	ZERO NINE TWO ZERO ZULU
09 minutes	ZERO NINE (past the next hour)

Aircraft headings are given in groups of three digits prefixed by the word “Heading”. If operating within the Southern Domestic Airspace, degrees are expressed in “magnetic”. If operating within the Northern Domestic Airspace, degrees are expressed in “True”.

Example:

005 degrees

HEADING ZERO ZERO FIVE

Aerodrome elevations are expressed in feet, prefixed by the words “Field Elevation”.

Example:

150	FIELD ELEVATION ONE FIVE ZERO

Transponder codes are preceded by the word SQUAWK.

Example:

code 1200

SQUAWK ONE TWO ZERO ZERO

Numbers containing a decimal point are expressed with the decimal point in the appropriate sequence by the word DECIMAL except that for VHF or UHF frequencies, the decimal point may be omitted if the omission is not likely to cause any misunderstanding.

5.8 Call Signs

5.8.1 Civil Aircraft

In radio communications, use phonetics at all times if the call sign consists of the aircraft’s registration.

The word “heavy” is used to indicate an aircraft is certified for a maximum take-off weight of 300 000 lbs or more.

After communication has been established, and when no likelihood of confusion exists, the word “heavy” may be omitted, and call signs may be abbreviated.

A MEDEVAC is a flight responding to a medical emergency for the transport of patients, organ donors, organs or other urgently needed life-saving medical material. This can also apply to certain medical flights, including helicopters, which may be designated as Air Ambulance Flights.

Canadian and Foreign Air Carriers:

(a) Initial contact: The operator’s radiotelephony designator followed by: the flight number, or the last four characters of the aircraft registration, and the word “heavy” if applicable.

Examples:

Air Canada 149 Heavy (AIR CANADA ONE FOUR NINE HEAVY)
Air Canada FTHA Heavy (AIR CANADA FOXTROT TANGO HOTEL ALFA HEAVY)
Speedbird GABCD Heavy (SPEEDBIRD GOLF ALFA BRAVO CHARLIE DELTA HEAVY)

(b) Subsequent communications: The word “heavy” may be omitted, and where the aircraft registration is used, it may be abbreviated to the operator’s radiotelephony designator and at least the last two characters of the aircraft registration.

Examples:

Air Canada HA (AIR CANADA HOTEL ALFA)
Speedbird CD (SPEEDBIRD CHARLIE DELTA)

Canadian Private Civil Aircraft and Canadian or Foreign Carriers Without an Assigned Radiotelephony Designator:

(a) Initial contact: The manufacturer’s name or the type of aircraft, followed by the last four characters of the registration.

Examples:

Cessna GADT (CESSNA GOLF ALFA DELTA TANGO)
Aztec FADT (AZTEC FOXTROT ALFA DELTA TANGO)

NOTE: The words “helicopter,” “glider” or “ultralight” are an acceptable substitute for the type of aircraft when these types of aircraft are used.

(b) Subsequent communications: May be abbreviated to the last three characters of the registration, if this abbreviation is initiated by ATS.

Examples:

Cessna GADT becomes “ADT” (ALFA DELTA TANGO)
Aztec FADT becomes “ADT” (ALFA DELTA TANGO)

Foreign Private Civil Aircraft:

(a) Initial contact: The manufacturer’s name or the type of aircraft, followed by the full aircraft registration.

Example:

Mooney-N6920K (MOONEY NOVEMBER SIX NINE TWO ZERO KILO).

(b) Subsequent communications: May be abbreviated to the last three characters of the registration, if this abbreviation is initiated by ATS.

Example:

Mooney-N6920K becomes 20K (TWO ZERO KILO).

Medical Evacuation Flight (MEDEVAC):

(a) Initial contact: The manufacturer’s name or type of aircraft or operator’s radiotelephony designator, followed by:

(i) the flight number and the word MEDEVAC, or

(ii) the last four characters of the aircraft registration and the word MEDEVAC.

Examples:

Austin 101 MEDEVAC (AUSTIN
ONE ZERO ONE MEDEVAC)
Cessna FABC MEDEVAC (CESSNA FOXTROT
ALFA BRAVO CHARLIE MEDEVAC).

(b) Subsequent communications: May be abbreviated as per normal procedures, retaining the word MEDEVAC.

Similar Sounding Call Signs:
If communicating with two or more aircraft that are using the same flight number or similar sounding identifications, ATS will advise each of the aircraft concerned of the other’s presence.

In order to further minimize the chance for call sign confusion, ATS may:

(a) restate the operator’s radiotelephony designator of the aircraft involved after the flight number, for emphasis.

Examples:

JAZZ EIGHT EIGHT ONE THREE JAZZ
TRANSPORT EIGHT ONE THREE TRANSPORT

(b) add the type of aircraft to the identification:

Example:

CHEROKEE ALFA BRAVO CHARLIE

or

(c) instruct aircraft using the same flight number or similar sounding identification to use:

(i) the aircraft registration; or

(ii) the operator’s radiotelephony designator, followed by at least the last two characters of the aircraft registration.

Examples:

JAZZ NOVEMBER DELTA
CANJET ECHO PAPA ALFA

5.8.2 Ground Stations

General

The aerodrome name as published in the CFS is used to form the call sign to the associated ground stations. When the aerodrome name is different from the community (location) name, it will be published following the community (location) name and will be separated by a diagonal (/). Exceptions should be listed in the COMM Section of the CFS.

Example:

TORONTO/LESTER B. PEARSON INTL ONT

COMM
TWR	Toronto		TORONTO TOWER

Other Examples of Call Signs:

	CFS		Call Sign
Area Control Centre	COMM CENTRE		MONTRÉAL CENTRE
Flight Service Station	RADIO		MONCTON RADIO
Terminal Control	TML		QUÉBEC TERMINAL
Arrival Control	ARR		VANCOUVER ARRIVAL
Departure Control	DEP		EDMONTON DEPARTURE
Clearance Delivery	CLNC DEL		OTTAWA CLEARANCE DELIVERY
Community Aerodrome	APRT RDO		REPULSE BAY AIRPORT
Radio Station			RADIO
Pilot to Forecaster	PMSV		COMOX METRO
Apron Advisory Service	APRON		MIRABEL APRON
Remote Communication Outlet	RCO	Rouyn rdo	ROUYN RADIO
Mandatory Frequency	MF	rdo	FREDERICTON RADIO
Aerodrome Traffic Frequency	ATF		MANIWAKI UNICOM
Peripheral Station	PAL	Winnipeg Ctr	WINNIPEG CENTRE
VFR Advisory	VFR ADV		TORONTO TERMINAL

5.8.3 RCO

An RCO is a facility remotely established from an FSS or flight information centre (FIC) to provide communications between aircraft and this FSS or FIC. They are intended only for FISE and RAAS communications. There is only one procedure to be used to establish communications on any RCO.

On initial contact, the pilot should state the identification of the ATS unit (FSS or FIC) controlling the RCO, the aircraft identification, and the name of the location of the RCO followed by the individual letters R-C-O in a non-phonetic form.

Example:

HALIFAX RADIO, CHEROKEE GOLF ALFA BRAVO CHARLIE ON THE FREDERICTON R-C-O

The name of the RCO assists the flight service specialist in identifying the RCO on which the call is made, as the same person can monitor many frequencies. The specialist will respond with the aircraft identification followed by the identification of the unit controlling the RCO.

Example:

GOLF ALFA BRAVO CHARLIE, HALIFAX RADIO

5.9 Standard Radio Telephony

General

The Radio communication Regulations specify that aeronautical radio communications are restricted to communications relating to

• the safety and navigation of an aircraft;
• the general operation of the aircraft; and
• the exchange of messages on behalf of the public.

In addition, a person may operate radio apparatus only to transmit a non-superfluous signal or a signal containing non-profane or non-obscene radiocommunications.

Pilots should

(a) send radio messages clearly and concisely using standard phraseology whenever practical;

(b) plan the content of the message before transmitting; and

(c) listen out before transmitting to avoid interference with other transmissions.

Message: Radiotelephony traffic generally consists of four parts: the call-up, the reply, the message and the acknowledgement.

Pilot: REGINA TOWER, (THIS IS) CESSNA FOXTROT BRAVO CHARLIE DELTA (OVER).

Tower: CESSNA FOXTROT BRAVO CHARLIE DELTA, REGINA TOWER.

Pilot: REGINA TOWER, FOXTROT BRAVO CHARLIE DELTA, TEN SOUTH THREE THOUSAND FIVE HUNDRED FEET VFR LANDING INSTRUCTIONS

Tower: BRAVO CHARLIE DELTA, REGINA TOWER, RUNWAY TWO SIX, WIND TWO THREE ZERO AT TEN, ALTIMETER TWO NINE NINE TWO, CLEARED TO THE CIRCUIT.

Pilot: BRAVO CHARLIE DELTA.

The terms “this is” and “over” may be omitted, and if no likelihood of confusion exists, the call sign for the agency being called maybe abbreviated as follows:

Pilot: TOWER, BRAVO CHARLIE DELTA, CONFIRM RIGHT TURN.

Message Acknowledgement: Pilots should acknowledge the receipt of all messages directed to them, including frequency changes. Such acknowledgement may take the form of a transmission of the aircraft call sign, a repeat of the clearance with the aircraft call sign or the call sign with an appropriate word(s).

Tower: VICTOR LIMA CHARLIE, CLEARED TO LAND.

Pilot: VICTOR LIMA CHARLIE.

Tower: FOXTROT VICTOR LIMA CHARLIE, CONFIRM YOU ARE AT FIVE THOUSAND.

Pilot: FOXTROT VICTOR LIMA CHARLIE, AFFIRMATIVE.

NOTE: The clicking of the microphone button as a form of acknowledgement is not an acceptable radio procedure.

5.10 Communications Checks

The readability scale from one to five has the following meaning:

1. unreadable;
2. readable now and then;
3. readable with difficulty;
4. readable; and
5. perfectly readable.

The strength scale from one to five used in HF communications has the following meaning:

1. bad;
2. poor;
3. fair;
4. good; and
5. excellent.

Communications checks are categorized as follows:

Signal Check - if the test is made while the aircraft is airborne.
Pre-flight Check - if the test is made prior to departure.
Maintenance Check - if the test is made by ground maintenance.

Pilot: THOMPSON RADIO, CESSNA FOXTROT ALFA BRAVO CHARLIE, RADIO CHECK ON FIVE SIX EIGHT ZERO.

Radio: FOXTROT ALFA BRAVO CHARLIE, THOMPSON RADIO, READING YOU STRENGTH FIVE, OVER.

5.11 Emergency Communications

General

An emergency situation is classified in one of the two following categories, in accordance with the degree of danger or hazard present:

1. distress is a condition of being threatened by serious and/or imminent danger and of requiring immediate assistance. The spoken word for distress is MAYDAY, and it is pronounced three times.
2. urgency is a condition concerning the safety of an aircraft or other vehicle, or of some person on board or within sight, but which does not require immediate assistance. The spoken word for urgency is PAN PAN, and it is pronounced three times.

The first transmission of the distress call and message by an aircraft should be on the air-to-ground frequency in use at the time. If the aircraft is unable to establish communication on the frequency in use, the distress call and message should be repeated on the HF general calling or distress frequency 3 023.5 kHz, 5 680 kHz, 121.5 MHz, 406.1 MHz, or other distress frequency available, such as 2 182 kHz, in an effort to establish communications with any ground station or the maritime service.

The distress call shall have absolute priority over all other transmissions. All stations hearing it shall immediately cease any transmission that may interfere with it and shall listen on the frequency used for the distress call.

Example of a distress message from an aircraft:

MAYDAY, MAYDAY, MAYDAY, THIS IS FOXTROT ZULU X-RAY YANKEE, FOXTROT ZULU X-RAY YANKEE, FOXTROT ZULU X-RAY YANKEE, FIVE ZERO MILES SOUTH OF YELLOWKNIFE AT ONE SEVEN TWO FIVE ZULU, FOUR THOUSAND, NORSEMAN, ICING, WILL ATTEMPT CRASH LANDING ON ICE, FOXTROT ZULU X-RAY YANKEE, OVER.

Example of an urgency message addressed to all stations:

PAN PAN, PAN PAN, PAN PAN, ALL STATIONS, ALL STATIONS, ALL STATIONS, THIS IS TIMMINS RADIO, TIMMINS RADIO, TIMMINS RADIO, EMERGENCY DESCENT AT TIMMINS AIRPORT, ATC INSTRUCTS ALL AIRCRAFT BELOW SIX THOUSAND FEET WITHIN RADIUS OF ONE ZERO MILES OF TIMMINS NDB LEAVE EAST AND NORTH COURSES IMMEDIATELY, THIS IS TIMMINS RADIO OUT.

Emergency procedures are contained in RAC and SAR.

121.5 MHz in the Air Navigation System (ANS)

Only control towers and FSSs have 121.5 MHz capability, and this emergency frequency is only monitored during these facilities’ hours of operation. Remote communication facilities (PAL, RAAS RCO and FISE RCO) do not have 121.5 MHz capability.

During an emergency, a pilot has the following options for communicating with ATS:

• When within radio reception of a control tower or FSS during the facility’s hours of operation, call ATS on the tower frequency/FSS mandatory frequency (MF) or 121.5 MHz. It is recommended that pilots use the normal or frequency in use at the time.
• When within radio reception of a remote communications facility (FISE RCO, RAAS RCO or PAL), call ATS on the published frequency.
  (Note: FISE RCOs and PALs operate 24 hr, while most RAAS RCOs operate part time).
• When out of range for VHF communications (for example at low altitude, along a highway corridor), pilots may use a cell phone if they have cell phone coverage (see COM 5.15).
• If beyond the radio reception of an ATS facility, or when outside the facility’s hours of operation, broadcast on 121.5 MHz or 126.7 MHz, or both, for assistance from other pilots who may be monitoring the frequency.

Satellite Voice

Inmarsat, in conjunction with ICAO, has developed a telephone numbering plan to facilitate the use of satellite voice by suitably equipped aircraft as a backup to the existing primary A/G facilities. The use of SATCOM voice for this purpose requires on board embedded equipment. Permanent satellite voice equipment is installed and tested in accordance with appropriate certification and airworthiness standards.

The telephone numbering plan assigns a code specific to each FIR. When a ground earth station receives the unique code from the aircraft via satellite, it is converted and the call is routed to the appropriate ATS unit.

For emergency communications, the Inmarsat short codes and public switched telephone network ( PSTN) numbers are as follows:

Location	Short Code/Inmarsat	PSTN Number
Gander Oceanic FIR	431603	1-709-651-5316
Gander Domestic FIR	431602	1-709-651-5315
Gander Radio	431613	1-709-651-5328
Moncton FIR	431604	1-506-867-7173
Montréal FIR	431605	1-514-633-3211
Toronto FIR	431606	1-905-676-4509
Winnipeg FIR	431608	1-204-983-8338
Edmonton FIR	431601	1-780-890-8397
Vancouver FIR	431607	1-604-586-4500

5.12 Monitoring of Emergency Frequency 121.5 MHz

A pilot should continuously monitor 121.5 MHz when operating within sparsely settled areas or when operating a Canadian aircraft over water more than 50 NM from shore unless:

1. essential cockpit duties or aircraft electronic equipment limitations do not permit simultaneous monitoring of two VHF frequencies; or
2. the pilot is using other VHF frequencies.

5.13 VHF Frequency Allocations

5.13.1 Air Traffic Services

ATS frequencies are published in the Canada Flight Supplements (CFS), aeronautical charts and the Canada Air Pilot (CAP).

5.13.2 Soaring

Frequency 123.4 MHz is allocated for the use of soaring activities, which include balloons, gliders, sailplanes, ultralights and hang gliders. The use of this frequency for these activities includes air-to-air, air-to-ground instructional and air-to-ground aerodrome traffic communications; the use of this frequency as an aerodrome traffic frequency (ATF) is normally restricted to privately operated aerodromes used primarily for these activities.

5.13.3 Air-to-Air

For air-to-air communications between pilots within the Canadian Southern Domestic Airspace, the correct frequency to use is 122.75 MHz; in the Northern Domestic Airspace and the North Atlantic, the frequency allocated by ICAO is 123.45 MHz.

5.14 Use of Frequency 5680 kHz

This frequency provides long-range A/G communications coverage in the remote areas of Canada for the provision of FISE beyond the range of VHF communications. Aircraft must use SSBs when communicating on 5680 kHz.

HF 5680 kHz RCOs

Location	Controlling ATS Unit
Baker Lake, Nunavut	North Bay FIC
Inuvik, Northwest Territories	North Bay FIC
Iqaluit, Nunavut	North Bay FIC
Kuujjuaq, Quebec	Quebec FIC
Kuujjuarapik, Quebec	Quebec FIC
Resolute Bay, Nunavut	North Bay FIC
Roberval, Quebec	Quebec FIC
St. Anthony, Newfoundland &Labrador	Halifax FIC
Thompson, Manitoba	Winnipeg FIC
Whitehorse, Yukon	Whitehorse FIC
Yellowknife, Northwest Territories	North Bay FIC

5.15 Phone Use During a Radio Communications Failure

COM 5.11 outlines the procedures for emergency communications using existing A/G facilities as the primary source of communications, and satellite voice as a backup.

In the event of an in-flight radio communications failure, and only after normal communications failure procedures have been followed (see RAC 6.3.2.1), the pilot-in-command may attempt to contact the appropriate NAV CANADA ATS unit by means of a conventional cell or satellite phone. Before placing the call, transponder-equipped aircraft should squawk Code 7600 (see RAC 1.9.7).

Public switched telephone network ( PSTN) numbers to be used in the event of a communication failure are included in COM 5.11 and published in the CFS.

Date modified:

2012-03-06

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