Commission Implementing Regulation (EU) No 923/2012 of 26 September 2012 laying down the common rules of the air and operational provisions regarding services and procedures in air navigation and amending Implementing Regulation (EU) No 1035/2011 and Regulations (EC) No 1265/2007, (EC) No 1794/2006, (EC) No 730/2006, (EC) No 1033/2006 and (EU) No 255/2010 Text with EEA relevance

• (b)As soon as an air traffic services unit becomes aware of an unidentified aircraft in its area, it shall endeavour to establish the identity of the aircraft whenever this is necessary for the provision of air traffic services or required by the appropriate military authorities in accordance with locally agreed procedures. To this end, the air traffic services unit shall take such of the following steps as are appropriate in the circumstances:

• (1) attempt to establish two-way communication with the aircraft;

• (2) inquire of other air traffic services units within the flight information region about the flight and request their assistance in establishing two-way communication with the aircraft;

• (3) inquire of air traffic services units serving the adjacent flight information regions about the flight and request their assistance in establishing two-way communication with the aircraft;

• (4) attempt to obtain information from other aircraft in the area;

• (5) the air traffic services unit shall, as necessary, inform the appropriate military unit as soon as the identity of the aircraft has been established.

• (c)In the case of a strayed or unidentified aircraft, the possibility of the aircraft being subject of unlawful interference shall be taken into account. Should the air traffic services unit consider that a strayed or unidentified aircraft may be the subject of unlawful interference, the appropriate authority designated by the State shall immediately be informed, in accordance with locally agreed procedures.

SERA.11012   Minimum Fuel and Fuel Emergency

• (a) When a pilot reports a state of minimum fuel/energy, the controller shall inform the pilot as soon as practicable of any anticipated delays or that no delays are expected.

• (b) When the level of fuel/energy renders declaring a situation of distress necessary, the pilot, in accordance with point SERA.14095, shall indicate that by using the radiotelephony distress signal (MAYDAY), preferably spoken three times, followed by the nature of the distress condition (FUEL).

SERA.11013   Degraded aircraft performance

• (a) Whenever, as a result of failure or degradation of navigation, communications, altimetry, flight control or other systems, aircraft performance is degraded below the level required for the airspace in which it is operating, the flight crew shall advise the ATC unit concerned without delay. Where the failure or degradation affects the separation minimum currently being employed, the controller shall take action to establish another appropriate type of separation or separation minimum.

• (b) Degradation or failure of the RNAV system When an aircraft cannot meet the specifications as required by the RNAV route or procedure, as a result of a failure or degradation of the RNAV system, a revised clearance shall be requested by the pilot.

• (c) Loss of vertical navigation performance required for reduced vertical separation minima (RVSM) airspace
• (1) The pilot shall inform ATC as soon as possible of any circumstances where the vertical navigation performance requirements for RVSM airspace cannot be maintained. In such cases, the pilot shall obtain a revised ATC clearance prior to initiating any deviation from the cleared route and/or flight level, whenever possible. When a revised ATC clearance cannot be obtained prior to such a deviation, the pilot shall obtain a revised clearance as soon as possible thereafter.
• (2) During operations in, or vertical transit through, RVSM airspace with aircraft not approved for RVSM operations, pilots shall report non-approved status as follows:
• (i) at initial call on any channel within RVSM airspace;
• (ii) in all requests for level changes; and
• (iii) in all read-backs of level clearances.
• (3) Air traffic controllers shall explicitly acknowledge receipt of messages from aircraft reporting RVSM non-approved status.
• (4) Degradation of aircraft equipment — pilot-reported:
• (i) When informed by the pilot of an RVSM-approved aircraft operating in RVSM airspace that the aircraft's equipment no longer meets the RVSM requirements, ATC shall consider the aircraft as non-RVSM-approved.
• (ii) ATC shall take action immediately to provide a minimum vertical separation of 600 m (2 000 ft) or an appropriate horizontal separation from all other aircraft concerned that are operating in RVSM airspace. An aircraft rendered non-RVSM-approved shall normally be cleared out of RVSM airspace by ATC when it is possible to do so.
• (iii) Pilots shall inform ATC, as soon as practicable, of any restoration of the proper functioning of equipment required to meet the RVSM requirements.
• (iv) The first ACC to become aware of a change in an aircraft's RVSM status shall coordinate with adjacent ACCs, as appropriate.
• (5) Severe turbulence — not forecast:
• (i) When an aircraft operating in RVSM airspace encounters severe turbulence due to weather or wake vortex that the pilot believes will impact the aircraft's capability to maintain its cleared flight level, the pilot shall inform ATC. ATC shall establish either an appropriate horizontal separation or an increased minimum vertical separation.
• (ii) ATC shall, to the extent possible, accommodate pilot requests for flight level and/or route changes and shall pass on traffic information, as required.
• (iii) ATC shall solicit reports from other aircraft to determine whether RVSM should be suspended entirely or within a specific flight level band and/or area.
• (iv) The ACC suspending RVSM shall coordinate with adjacent ACCs such suspension(s) and any required adjustments to sector capacities, as appropriate, to ensure an orderly progression of the transfer of traffic.
• (6) Severe turbulence — forecast:
• (i) When a meteorological forecast is predicting severe turbulence within RVSM airspace, ATC shall determine whether RVSM should be suspended and, if so, for how long and for which specific flight level(s) and/or area.
• (ii) In cases where RVSM will be suspended, the ACC suspending RVSM shall coordinate with adjacent ACCs with regard to the flight levels appropriate for the transfer of traffic, unless a contingency flight level allocation scheme has been determined by letter of agreement. The ACC suspending RVSM shall also coordinate applicable sector capacities with adjacent ACCs, as appropriate.

SERA.11014   ACAS resolution advisory (RA)

• (a) ACAS II shall be used during flight, except as provided in the minimum equipment list specified in Commission Regulation (EU) No 965/2012 (4)  in a mode that enables RA indications to be produced for the flight crew when undue proximity to another aircraft is detected. This shall not apply if inhibition of RA indication mode (using traffic advisory (TA) indication only or equivalent) is called for by an abnormal procedure or due to performance-limiting conditions.

• (b) In the event of an ACAS RA, pilots shall:
• (1) respond immediately by following the RA, as indicated, unless doing so would jeopardise the safety of the aircraft;
• (2) follow the RA even if there is a conflict between the RA and an ATC instruction to manoeuvre;
• (3) not manoeuvre in the opposite sense to an RA;
• (4) as soon as possible, as permitted by flight crew workload, notify the appropriate ATC unit of any RA which requires a deviation from the current ATC instruction or clearance;
• (5) promptly comply with any modified RAs;
• (6) limit the alterations of the flight path to the minimum extent necessary to comply with the RAs;
• (7) promptly return to the terms of the ATC instruction or clearance when the conflict is resolved; and
• (8) notify ATC when returning to the current clearance.

• (c) When a pilot reports an ACAS RA, the controller shall not attempt to modify the aircraft flight path until the pilot reports ‘CLEAR OF CONFLICT’.

• (d) Once an aircraft departs from its ATC clearance or instruction in compliance with an RA, or a pilot reports an RA, the controller ceases to be responsible for providing separation between that aircraft and any other aircraft affected as a direct consequence of the manoeuvre induced by the RA. The controller shall resume responsibility for providing separation to all the affected aircraft when:
• (1) the controller acknowledges a report from the flight crew that the aircraft has resumed the current clearance; or
• (2) the controller acknowledges a report from the flight crew that the aircraft is resuming the current clearance and issues an alternative clearance which is acknowledged by the flight crew.

SERA.11015   Interception

• (a)Except for intercept and escort service provided on request to an aircraft, interception of civil aircraft shall be governed by appropriate regulations and administrative directives issued by Member States in compliance with the Convention on International Civil Aviation, and in particular Article 3(d) under which ICAO Contracting States undertake, when issuing regulations for their State aircraft, to have due regard for the safety of navigation of civil aircraft.

• (b)The pilot-in-command of a civil aircraft, when intercepted, shall:

• (1) immediately follow the instructions given by the intercepting aircraft, interpreting and responding to visual signals in accordance with the specifications in Tables S11-1 and S11-2;

• (2) notify, if possible, the appropriate air traffic services unit;

• (3) attempt to establish radio-communication with the intercepting aircraft or with the appropriate intercept control unit, by making a general call on the emergency frequency 121,5 MHz, giving the identity of the intercepted aircraft and the nature of the flight; and if no contact has been established and if practicable, repeating this call on the emergency frequency 243 MHz;

• (4) if equipped with SSR transponder, select Mode A, Code 7700, unless otherwise instructed by the appropriate air traffic services unit;

• (5) if equipped with ADS-B or ADS-C, select the appropriate emergency functionality, if available, unless otherwise instructed by the appropriate air traffic services unit. Table S11-1 Signals initiated by intercepting aircraft and responses by intercepted aircraft Series INTERCEPTING Aircraft Signals Meaning INTERCEPTED Aircraft Responds Meaning 1 DAY or NIGHT — Rocking aircraft and flashing navigational lights at irregular intervals (and landing lights in the case of a helicopter) from a position slightly above and ahead of, and normally to the left of, the intercepted aircraft (or to the right if the intercepted aircraft is a helicopter) and, after acknowledgement, a slow level turn, normally to the left (or to the right in the case of a helicopter) on the desired heading. Note 1 Meteorological conditions or terrain may require the intercepting aircraft to reverse the positions and direction of turn given above in Series 1. Note 2 If the intercepted aircraft is not able to keep pace with the intercepting aircraft, the latter is expected to fly a series of race-track patterns and to rock the aircraft each time it passes the intercepted aircraft. You have been intercepted. Follow me. DAY or NIGHT — Rocking aircraft, flashing navigational lights at irregular intervals and following. Understood, will comply. 2 DAY or NIGHT — An abrupt breakaway manoeuvre from the intercepted aircraft consisting of a climbing turn of 90 degrees or more without crossing the line of flight of the intercepted aircraft. You may proceed. DAY or NIGHT — Rocking the aircraft. Understood, will comply.

3 DAY or NIGHT – Lowering landing gear (if fitted), showing steady landing lights and overflying runway in use or, if the intercepted aircraft is a helicopter / VTOL-capable aircraft, overflying the helicopter / VTOL-capable aircraft landing area. In the case of helicopters /VTOL-capable aircraft, the intercepting helicopter / VTOL-capable aircraft makes a landing approach, coming to hover near the landing area.

Land at this aerodrome. DAY or NIGHT – Lowering landing gear, (if fitted), showing steady landing lights and following the intercepting aircraft and, if, after overflying the runway in use or helicopter / VTOL-capable aircraft landing area, landing is considered safe, proceeding to land. Understood, will comply.

Table S11-2

Signals initiated by intercepted aircraft and responses by intercepting aircraft

Series	INTERCEPTED Aircraft Signals	Meaning	INTERCEPTING Aircraft Responds	Meaning
4	DAY or NIGHT – Raising landing gear (if fitted) and flashing landing lights while passing over runway in use or helicopter / VTOL-capable aircraft landing area at a height exceeding 300 m (1 000 ft) but not exceeding 600 m (2 000 ft) (in the case of a helicopter, at a height exceeding 50 m (170 ft) but not exceeding 100 m (330 ft)) above the aerodrome level, and continuing to circle runway in use or helicopter / VTOL-capable aircraft landing area. If unable to flash landing lights, flash any other lights available.	Aerodrome you have designated is inadequate.	DAY or NIGHT – If it is desired that the intercepted aircraft follow the intercepting aircraft to an alternate aerodrome, the intercepting aircraft raises its landing gear (if fitted) and uses the Series 1 signals prescribed for intercepting aircraft. If it is decided to release the intercepted aircraft, the intercepting aircraft uses the Series 2 signals prescribed for intercepting aircraft.	Understood, follow me. Understood, you may proceed.
5	DAY or NIGHT — Regular switching on and off of all available lights but in such a manner as to be distinct from flashing lights.	Cannot comply.	DAY or NIGHT — Use Series 2 signals prescribed for intercepting aircraft.	Understood.
6	DAY or NIGHT — Irregular flashing of all available lights.	In distress.	DAY or NIGHT — Use Series 2 signals prescribed for intercepting aircraft.	Understood.

• (c)If any instructions received by radio from any sources conflict with those given by the intercepting aircraft by visual signals, the intercepted aircraft shall request immediate clarification while continuing to comply with the visual instructions given by the intercepting aircraft.

• (d)If any instructions received by radio from any sources conflict with those given by the intercepting aircraft by radio, the intercepted aircraft shall request immediate clarification while continuing to comply with the radio instructions given by the intercepting aircraft.

- (e)If radio contact is established during interception but communication in a common language is not possible, attempts shall be made to convey instructions, acknowledgement of instructions and essential information by using the phrases and pronunciations in Table S11-3 and transmitting each phrase twice:

Table S11-3

Phrases for use by INTERCEPTING aircraft	Phrases for use by INTERCEPTING aircraft	Phrases for use by INTERCEPTING aircraft	Phrases for use by INTERCEPTED aircraft	Phrases for use by INTERCEPTED aircraft	Phrases for use by INTERCEPTED aircraft
Phrase	Pronunciation [^E0009]	Meaning	Phrase	Pronunciation [^E0009]	Meaning
CALL SIGN	KOL SA-IN	What is your call sign?	CALL SIGN (call sign) [^E0010]	KOL SA-IN (call sign)	My call sign is (call sign)
FOLLOW	FOL-LO	Follow me	WILCO	VILL-KO	Understood, will comply
DESCEND	DEE-SEND	Descend for landing	—
			CAN NOT	KANN NOTT	Unable to comply
YOU LAND	YOU LAAND	Land at this aerodrome	REPEAT	REE-PEET	Repeat your instruction
			AM LOST	AM LOSST	Position unknown
PROCEED	PRO-SEED	You may proceed
			MAYDAY	MAYDAY	I am in distress
			HIJACK [^E0011]	HI-JACK	I have been hijacked
			LAND (place name)	LAAND (place name)	I request to land at (place name)
			DESCEND	DEE-SEND	I require descent

In the second column, syllables to be emphasised are underlined.

The call sign required to be given is that used in radiotelephony communications with air traffic services units and corresponding to the aircraft identification in the flight plan.

Circumstances may not always permit, nor make desirable, the use of the phrase ‘HIJACK’.

• (f)As soon as an air traffic services unit learns that an aircraft is being intercepted in its area of responsibility, it shall take such of the following steps as are appropriate in the circumstances:

• (1) attempt to establish two-way communication with the intercepted aircraft via any means available, including the emergency radio frequency 121,5 MHz, unless such communication already exists;

• (2) inform the pilot of the intercepted aircraft of the interception;

• (3) establish contact with the intercept control unit maintaining two-way communication with the intercepting aircraft and provide it with available information concerning the aircraft;

• (4) relay messages between the intercepting aircraft or the intercept control unit and the intercepted aircraft, as necessary;

• (5) in close coordination with the intercept control unit take all necessary steps to ensure the safety of the intercepted aircraft;

• (6) inform air traffic services units serving adjacent flight information regions if it appears that the aircraft has strayed from such adjacent flight information regions.

• (g)As soon as an air traffic services unit learns that an aircraft is being intercepted outside its area of responsibility, it shall take such of the following steps as are appropriate in the circumstances:

• (1) inform the air traffic services unit serving the airspace in which the interception is taking place, providing this unit with available information that will assist in identifying the aircraft and requesting it to take action in accordance with (f);

- (2) relay messages between the intercepted aircraft and the appropriate air traffic services unit, the intercept control unit or the intercepting aircraft.

SECTION 12

Services related to meteorology — Aircraft observations and reports by voice communications

SERA.12001   Types of aircraft observations

• (a)The following aircraft observations shall be made during any phase of the flight:

• (1) special aircraft observations; and

- (2) other non-routine aircraft observations.

SERA.12005   Special aircraft observations

• (a)Special observations shall be made and reported by all aircraft whenever the following conditions are encountered or observed:

• (1) moderate or severe turbulence; or

• (2) moderate or severe icing; or

• (3) severe mountain wave; or

• (4) thunderstorms, without hail, that are obscured, embedded, widespread or in squall lines; or

• (5) thunderstorms, with hail, that are obscured, embedded, widespread or in squall lines; or

• (6) heavy dust storm or heavy sandstorm; or

• (7) volcanic ash cloud; or

• (8) pre-eruption volcanic activity or a volcanic eruption; or

• (9) the runway braking action encountered is not as good as reported.

• (b)Competent authorities shall prescribe as necessary other conditions which shall be reported by all aircraft when encountered or observed.

• (c)Flight crews shall compile the reports using forms based on the model AIREP SPECIAL form as set out in point A of Appendix 5. Those reports shall comply with the detailed instructions for reporting, as provided in point 2 of Appendix 5.

• (1) The detailed instructions, including the formats of messages and the phraseologies provided in Appendix 5, shall be used by flight crews when transmitting air-reports and by ATS units when retransmitting such reports.

- (2) Special air-reports containing observations of volcanic activity shall be recorded on the special air-report of volcanic activity form. Forms based on the model form for special air-reports of volcanic activity set out in point B of Appendix 5 shall be provided for flight crews operating on routes which could be affected by volcanic ash clouds.

SERA.12010   Other non-routine aircraft observations

When other meteorological conditions not listed under SERA.12005 (a), e.g. wind shear, are encountered and which, in the opinion of the pilot-in-command, may affect the safety or markedly affect the efficiency of other aircraft operations, the pilot-in-command shall advise the appropriate air traffic services unit as soon as practicable.

SERA.12015   Reporting of aircraft observations by voice communication

• (a)Aircraft observations shall be reported during flight at the time the observation is made or as soon thereafter as is practicable.

- (b)Aircraft observations shall be reported as air-reports and shall comply with the technical specifications in Appendix 5.

SERA.12020   Exchange of air-reports

• (a) Air traffic services units shall transmit, as soon as practicable, special and non-routine air-reports to:
• (1) other aircraft concerned;
• (2) the associated meteorological watch office (MWO) in accordance with point 3 of Point A of Appendix 5; and
• (3) other air traffic services units concerned.

• (b) When receiving special air-reports by voice communications concerning braking action which does not correspond to the runway condition report, air traffic services units shall forward them without delay to the appropriate aerodrome operator.

- (c) Transmissions to aircraft shall be repeated at a frequency and continued for a period of time which shall be determined by the air traffic services unit concerned.

SECTION 13

SSR transponder and ADS-B transmitters

SERA.13001   Operation of an SSR transponder

• (a) When an aircraft carries a serviceable SSR transponder, the pilot shall operate the transponder at all times during flight, regardless of whether the aircraft is within or outside airspace where SSR is used for ATS purposes.

• (b) Pilots shall not operate the IDENT feature unless requested by ATS.

- (c) Except for flight in airspace designated by the competent authority for mandatory operation of transponder, aircraft without sufficient electrical power supply are exempted from the requirement to operate the transponder at all times.

SERA.13005   SSR transponder Mode A code setting

• (a) To indicate that it is in a specific contingency situation, the pilot of an aircraft equipped with SSR shall:
• (1) select Code 7700 to indicate a state of emergency unless ATC has previously directed the pilot to operate the transponder on a specified code. In the latter case, a pilot may nevertheless select Code 7700 whenever there is a specific reason to believe that this would be the best course of action;
• (2) select Code 7600 to indicate a state of radio-communication failure;
• (3) attempt to select Code 7500 to indicate a state of unlawful interference. If circumstances so warrant, Code 7700 should be used instead.

• (b) Except in the cases described in (a) above, the pilot shall:
• (1) select codes as instructed by the ATS unit; or
• (2) in the absence of ATS instructions related to code setting, select code 2000 or another code as prescribed by the competent authority; or
• (3) when not receiving air traffic services, select code 7000 in order to improve the detection of suitably equipped aircraft unless otherwise prescribed by the competent authority.

- (c) When it is observed that the code shown on the situation display is different from what has been assigned to the aircraft:

• (1) the pilot shall be requested to confirm the code selected and, if the situation warrants, to reselect the correct code; and
• (2) if the discrepancy between assigned and displayed codes still persists, the pilot may be requested to stop the operation of the aircraft's transponder. The next control position and any other affected unit using SSR and/or multilateration (MLAT) in the provision of ATS shall be informed accordingly.

SERA.13010   Pressure-altitude-derived information

• (a) When the aircraft carries serviceable Mode C equipment, the pilot shall continuously operate this mode unless otherwise dictated by ATC.

- (b) Unless otherwise prescribed by the competent authority, verification of the pressure-altitude-derived level information displayed shall be effected at least once by each suitably equipped ATS unit on initial contact with the aircraft concerned or, if this is not feasible, as soon as possible thereafter.

SERA.13015   On-board aircraft identification setting

• (a) Aircraft equipped with a Mode S or ADS-B transmitter that has an aircraft identification feature shall transmit the aircraft identification as specified in the flight plan or, when no flight plan has been filed, the aircraft registration, unless the aircraft operator holds an approval from the competent authority to use other than the aircraft registration as aircraft identification for flights without a flight plan.

• (b) Whenever it is observed on the situation display that the aircraft identification transmitted by an aircraft equipped with a Mode S or ADS-B transmitter is different from that expected from the aircraft, the pilot shall be requested to confirm and, if necessary, re-enter the correct aircraft identification.

- (c) If, following confirmation by the pilot that the correct aircraft identification has been set on the Mode S or ADS-B transmitter identification feature, the discrepancy continues to exist, the air traffic services unit shall take the following actions:

• (1) inform the pilot of the persistent discrepancy;
• (2) where possible, correct the label showing the aircraft identification on the situation display; and
• (3) notify the next control position and any other unit concerned using Mode S or ADS-B for identification purposes that the aircraft identification transmitted by the aircraft is erroneous.

SERA.13020   SSR transponder failure when the carriage of a functioning transponder is mandatory

• (a) In case of a transponder failure after departure, ATC units shall attempt to provide for continuation of the flight to the destination aerodrome in accordance with the flight plan. Pilots may, however, be expected to comply with specific restrictions.

- (b) In the case of a transponder which has failed and cannot be restored before departure, pilots shall:

• (1) inform ATS as soon as possible, preferably before submission of a flight plan;
• (2) insert in Item 10 of the ICAO flight plan form under SSR the character ‘N’ for complete unserviceability of the transponder or, in case of partial transponder failure, insert the character corresponding to the remaining transponder capability; and
• (3) comply with any published procedures for requesting an exemption from the requirements to carry a functioning SSR transponder.

SECTION 14

Voice communication procedures

SERA.14001   General

Standardised phraseology shall be used in all situations for which it has been specified. Only when standardised phraseology cannot serve an intended transmission, plain language shall be used.

SERA.14005   Categories of messages

• (a) The categories of messages handled by the aeronautical mobile service, and the order of priority in the establishment of communications and the transmission of messages shall be in accordance with Table S14-1. Table S14-1 Message category and radiotelephony order of priority signal Radiotelephony signal (a) Distress calls, distress messages and distress traffic MAYDAY (b) Urgency messages, including messages preceded by the medical transports signal PAN PAN or PAN PAN MEDICAL (c) Communications relating to direction finding — (d) Flight safety messages — (e) Meteorological messages — (f) Flight regularity messages —

• (b) Distress messages and distress traffic shall be handled in accordance with the provisions of point SERA.14095.

- (c) Urgency messages and urgency traffic, including messages preceded by the medical transports signal, shall be handled in accordance with the provisions of point SERA.14095.

SERA.14010   Flight safety messages

Flight safety messages shall comprise the following:

• (a) movement and control messages;

• (b) messages originated by an aircraft operator or by an aircraft, of immediate concern to an aircraft in flight;

• (c) meteorological advice of immediate concern to an aircraft in flight or about to depart (individually communicated or for broadcast);

- (d) other messages concerning aircraft in flight or about to depart.

SERA.14015   Language to be used in air-ground communication

• (a) The air-ground radiotelephony communications shall be conducted in the English language or in the language normally used by the station on the ground.

• (b) The English language shall be available, on request of any aircraft, at all stations on the ground serving designated aerodromes and routes used by international air services. Unless otherwise prescribed by the competent authority for specific cases, the English language shall be used for communications between the ATS unit and aircraft, at aerodromes with more than 50 000 international IFR movements per year. Member States, where at the date of entry into force of this Regulation, the English language is not the only language used for communications between the ATS unit and aircraft at such aerodromes, may decide not to apply the requirement to use the English language and inform the Commission accordingly. In that case, those Member States shall, by 31 December 2017 at the latest, conduct a study on the possibility to require the use of the English language for communications between the ATS unit and aircraft at those aerodromes for reasons of safety, so as to avoid incursions of aircraft on an occupied runway or other safety risks, while taking into account the applicable provisions of Union and national law on the use of languages. They shall make that study public and communicate its conclusions to the Agency and the Commission.

- (c) The languages available at a given station on the ground shall form part of the Aeronautical Information Publications and other published aeronautical information concerning such facilities.

SERA.14020   Word spelling in radiotelephony

When proper names, service abbreviations and words of which the spelling is doubtful are spelled out in radiotelephony, the alphabet in the Table S14-2 shall be used.

Table S14-2

The radiotelephony spelling alphabet

| Letter | Word | Approximate pronunciation (Latin alphabet representation) |

| --- | --- | --- | | A | Alfa | AL FAH | | B | Bravo | BRAH VOH | | C | Charlie | CHAR LEE or SHAR LEE | | D | Delta | DELL TAH | | E | Echo | ECK OH | | F | Foxtrot | FOKS TROT | | G | Golf | GOLF | | H | Hotel | HO TELL | | I | India | IN DEE AH | | J | Juliett | JEW LEE ETT | | K | Kilo | KEY LOH | | L | Lima | LEE MAH | | M | Mike | MIKE | | N | November | NO VEM BER | | O | Oscar | OSS CAH | | P | Papa | PAH PAH | | Q | Quebec | KEH BECK | | R | Romeo | ROW ME OH | | S | Sierra | SEE AIR RAH | | T | Tango | TANG GO | | U | Uniform | YOU NEE FORM or OO NEE FORM | | V | Victor | VIK TAH | | W | Whiskey | WISS KEY | | X | X-ray | ECKS RAY | | Y | Yankee | YANG KEY | | Z | Zulu | ZOO LOO | | In the approximate representation using the Latin alphabet, syllables to be emphasised are underlined. | In the approximate representation using the Latin alphabet, syllables to be emphasised are underlined. | In the approximate representation using the Latin alphabet, syllables to be emphasised are underlined. |

SERA.14025   Principles governing the identification of ATS routes other than standard departure and arrival routes

• (a) Use of ATS route designators in communications
• (1) In voice communications, the basic letter of a designator shall be spoken in accordance with the spelling alphabet as defined in Table S14-2.
• (2) Where the prefixes K, U or S are used, they shall, in voice communications, be spoken as follows: (i) K— KOPTER (ii) U— UPPER (iii) S— SUPERSONIC

- (b) The word ‘kopter’ shall be pronounced as in the word ‘helicopter’ and the words ‘upper’ and ‘supersonic’ as in the English language.

SERA.14026   Significant points

Normally the plain language name for significant points marked by the site of a radio navigation aid, or the unique five-letter pronounceable ‘name-code’ for significant points not marked by the site of a radio navigation aid, shall be used to refer to the significant point in voice communications. If the plain language name for the site of a radio navigation aid is not used, it shall be replaced by the coded designator which, in voice communications, shall be spoken in accordance with the spelling alphabet.

SERA.14030   Use of designators for standard instrument departure and arrival routes

The plain language designator for standard instrument departure or arrival routes shall be used in voice communications.

SERA.14035   Transmission of numbers in radiotelephony

• (a)Transmission of numbers

• (1) All numbers used in the transmission of aircraft call sign, headings, wind direction and speed, and runway shall be transmitted by pronouncing each digit separately.
• (i) Flight levels shall be transmitted by pronouncing each digit separately, except for the case of flight levels in whole hundreds.
• (ii) The altimeter setting shall be transmitted by pronouncing each digit separately, except for the case of a setting of 1 000 hPa, which shall be transmitted as ‘ONE THOUSAND’.
• (iii) All numbers used in the transmission of transponder codes shall be transmitted by pronouncing each digit separately except that, when the transponder codes contain whole thousands only, the information shall be transmitted by pronouncing the digit in the number of thousands followed by the word ‘THOUSAND’.

• (2) All numbers used in transmission of other information than those described in point (a)(1) shall be transmitted by pronouncing each digit separately, except that all numbers containing 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’.

• (3) In cases where there is a need to clarify the number transmitted as whole thousands and/or whole hundreds, the number shall be transmitted by pronouncing each digit separately.

• (4) When providing information regarding the relative bearing to an object or to conflicting traffic in terms of the 12-hour clock, the information shall be given pronouncing the digits together such as ‘TEN O'CLOCK’ or ‘ELEVEN O'CLOCK’.

• (5) Numbers containing a decimal point shall be transmitted as prescribed in point (a)(1) with the decimal point in appropriate sequence, indicated by the word ‘DECIMAL’.

- (6) All six digits of the numerical designator shall be used to identify the transmitting channel in very high frequency (VHF) radiotelephony communications, except in the case of both the fifth and sixth digits being zeros, in which case only the first four digits shall be used.

SERA.14040   Pronunciation of numbers

When the language used for communication is English, numbers shall be transmitted using the pronunciation shown in Table S14-3:

Table S14-3

| Numeral or numeral element | Pronunciation |

| --- | --- | | 0 | ZE-RO | | 1 | WUN | | 2 | TOO | | 3 | TREE | | 4 | FOW-er | | 5 | FIFE | | 6 | SIX | | 7 | SEV-en | | 8 | AIT | | 9 | NIN-er | | 10 | TEN | | 11 | EE-LE-VEN | | 12 | TWELF | | Decimal | DAY-SEE-MAL | | Hundred | HUN-dred | | Thousand | TOU-SAND |

SERA.14045   Transmitting technique

• (a) Transmissions shall be conducted concisely in a normal conversational tone.

• (b) The following words and phrases shall be used in radiotelephony communications as appropriate and shall have the meaning ascribed in Table S14-4: Table S14-4 Phrase Meaning ACKNOWLEDGE ‘Let me know that you have received and understood this message.’ AFFIRM ‘Yes.’ APPROVED ‘Permission for proposed action granted.’ BREAK ‘I hereby indicate the separation between portions of the message.’ BREAK BREAK ‘I hereby indicate the separation between messages transmitted to different aircraft in a very busy environment.’ CANCEL ‘Annul the previously transmitted clearance.’ CHECK ‘Examine a system or procedure.’ CLEARED ‘Authorised to proceed under the conditions specified.’ CONFIRM ‘I request verification of: (clearance, instruction, action, information).’ CONTACT ‘Establish communications with…’ CORRECT ‘True’ or ‘Accurate’. CORRECTION ‘An error has been made in this transmission (or message indicated). The correct version is…’ DISREGARD ‘Ignore.’ HOW DO YOU READ ‘What is the readability of my transmission?’ (see point SERA.14070(c)) I SAY AGAIN ‘I repeat for clarity or emphasis.’ MAINTAIN ‘Continue in accordance with the condition(s) specified’ or in its literal sense. MONITOR ‘Listen out on (frequency).’ NEGATIVE ‘No’or‘Permission not granted’or‘That is not correct’or‘Not capable’. OVER ‘My transmission is ended, and I expect a response from you.’ OUT ‘This exchange of transmissions is ended and no response is expected.’ READ BACK ‘Repeat all, or the specified part, of this message back to me exactly as received.’ RECLEARED ‘A change has been made to your last clearance and this new clearance supersedes your previous clearance or part thereof.’ REPORT ‘Pass me the following information…’ REQUEST ‘I should like to know…’or‘I wish to obtain…’ ROGER ‘I have received all of your last transmission.’ 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.’ UNABLE ‘I cannot comply with your request, instruction, or clearance.’ 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.’

- (c) The expression ‘TAKE-OFF’ shall only be used in radiotelephony when an aircraft is cleared for take-off or when cancelling a take-off clearance.

SERA.14050   Radiotelephony call signs for aircraft

• (a) Full call signs: An aircraft radiotelephony call sign shall be one of the following types: (1) Type (a) — the characters corresponding to the registration marking of the aircraft; or (2) Type (b) — the telephony designator of the aircraft operator, followed by the last four characters of the registration marking of the aircraft; (3) Type (c) — the telephony designator of the aircraft operator, followed by the flight identification.

- (b) Abbreviated call signs:

The aircraft radiotelephony call signs shown in point (a), with the exception of Type (c), may be abbreviated under the circumstances prescribed in point SERA.14055(c). Abbreviated call signs shall be in the following form: (1) Type (a) — the first character of the registration and at least the last two characters of the call sign; (2) Type (b) — the telephony designator of the aircraft operator, followed by at least the last two characters of the call sign; (3) Type (c) — no abbreviated form.

SERA.14055   Radiotelephony procedures

• (a) An aircraft shall not change the type of its radiotelephony call sign during flight, except temporarily on the instruction of an ATC unit in the interests of safety. Except for reasons of safety, no transmission shall be directed to an aircraft during take-off, during the last part of the final approach or during the landing roll.

• (b) Establishment of radiotelephony communications
• (1) Full radiotelephony call signs shall always be used when establishing communication. When establishing communication, aircraft shall start their call by the designation of the station called, followed by the designation of the station calling.
• (2) The reply to the above calls shall use the call sign of the station calling, followed by the call sign of the station answering, which shall be considered an invitation to proceed with transmission by the station calling. For transfers of communication within one ATS unit, the call sign of the ATS unit may be omitted, when so authorised by the competent authority.
• (3) Communications shall commence with a call and a reply when it is desired to establish contact, except that, when it is certain that the station called will receive the call, the calling station may transmit the message, without waiting for a reply from the station called.

- (c) Subsequent radiotelephony communications

• (1) Abbreviated radiotelephony call signs, as prescribed in point SERA.14050(b), shall be used only after satisfactory communication has been established and provided that no confusion is likely to arise. An aircraft shall use its abbreviated call sign only after it has been addressed in this manner by the aeronautical station.
• (2) When issuing ATC clearances and reading back such clearances, controllers and pilots shall always add the call sign of the aircraft to which the clearance applies. For other than those occasions, continuous two-way communication after contact has been established shall be permitted without further identification or call until termination of the contact.

SERA.14060   Transfer of VHF communications

• (a) An aircraft shall be advised by the appropriate ATS unit to transfer from one radio frequency to another in accordance with agreed procedures. In the absence of such advice, the aircraft shall notify the ATS unit before such a transfer takes place.

- (b) When establishing initial contact on, or when leaving, a VHF frequency, an aircraft shall transmit such information as may be prescribed by the ANSP responsible for the provision of services and approved by the competent authority.

SERA.14065   Radiotelephony procedures for air-ground voice communication channel changeover

• (a) Unless otherwise prescribed by the ANSP responsible for the provision of services and approved by the competent authority, the initial call to an air traffic services unit after a change of the air-ground voice communication channel shall contain the following elements:
• (1) the designation of the ATS unit being called;
• (2) call sign, immediately followed by the word ‘Heavy’ or ‘Super’ corresponding, as appropriate, to the wake turbulence category of the aircraft;
• (3) level, including passing and cleared levels, if not maintaining the cleared level;
• (4) speed, if assigned by ATC; and
• (5) additional elements, as required by the ANSP responsible for the provision of services and approved by the competent authority.

• (b) Pilots shall provide level information at the nearest full 30 m or 100 ft as indicated on the pilot's altimeter.

- (c) Initial call to aerodrome control tower

For aircraft being provided with aerodrome control service, the initial call shall contain: - (1) the designation of the ATS unit being called; - (2) call sign, immediately followed by the word ‘Heavy’ or ‘Super’ corresponding, as appropriate, to the wake turbulence category of the aircraft; - (3) position; and - (4) additional elements, as required by the ANSP responsible for the provision of services and approved by the competent authority.

SERA.14070   Test procedures

• (a) The form of test transmissions shall be as follows:
• (1) the identification of the station being called;
• (2) the identification of the station calling;
• (3) the words ‘RADIO CHECK’;
• (4) the frequency being used.

• (b) The reply to a test transmission shall be as follows:
• (1) the identification of the station requesting the test;
• (2) the identification of the station replying;
• (3) information regarding the readability of the station requesting the test transmission.

- (c) When the tests are made, the following readability scale shall be used:

Readability Scale 1 Unreadable 2 Readable now and then 3 Readable but with difficulty 4 Readable 5 Perfectly readable

SERA.14075   Exchange of communications

• (a) Communications shall be concise and unambiguous, using standard phraseology whenever available.
• (1) When transmitted by an aircraft, the acknowledgement of receipt of a message shall comprise the call sign of that aircraft.
• (2) When acknowledgement of receipt is transmitted by an ATS unit to an aircraft, it shall comprise the call sign of the aircraft, followed if considered necessary, by the call sign of the ATS unit.

• (b) End of conversation. A radiotelephone conversation shall be terminated by the receiving ATS unit or the aircraft using its own call sign.

• (c) Corrections and repetitions
• (1) When an error has been made in transmission, the word ‘CORRECTION’ shall be spoken, the last correct group or phrase repeated, and then the correct version transmitted.
• (2) If a correction can best be made by repeating the entire message, the phrase ‘CORRECTION, I SAY AGAIN’ shall be used before the message is transmitted a second time.
• (3) If the receiving station is in doubt as to the correctness of the message received, a repetition either in full or in part shall be requested.
• (4) If repetition of an entire message is required, the words ‘SAY AGAIN’ shall be spoken. If repetition of a portion of a message is required, the phrase: ‘SAY AGAIN ALL BEFORE… (first word satisfactorily received)’ shall be used; or ‘SAY AGAIN… (word before missing portion) TO…(word after missing portion)’; or ‘SAY AGAIN ALL AFTER… (last word satisfactorily received)’.

- (d) If, in checking the correctness of a read-back, incorrect items are noticed, the words ‘NEGATIVE I SAY AGAIN’ shall be transmitted at the conclusion of the read-back followed by the correct version of the items concerned.

SERA.14080   Communications watch/Hours of service

• (a) During flight, aircraft shall maintain watch as required by the competent authority and shall not cease watch, except for reasons of safety, without informing the ATS unit concerned.
• (1) Aircraft on long over-water flights or on flights over designated areas over which the carriage of an emergency locator transmitter (ELT) is required, shall continuously guard the VHF emergency frequency 121,5 MHz, except for those periods when aircraft carry out communications on other VHF channels or when airborne equipment limitations or cockpit duties do not permit simultaneous guarding of two channels.
• (2) Aircraft shall continuously guard the VHF emergency frequency 121,5 MHz in areas or over routes where the possibility of interception of aircraft or other hazardous situations exists, and a requirement has been established by the competent authority.

• (b) Aeronautical stations shall maintain a continuous listening watch on VHF emergency channel 121,5 MHz during the hours of service of the units at which it is installed. Where two or more such stations are co-located, provision of 121,5 MHz listening watch at one of them shall meet that requirement.

- (c) When it is necessary for an aircraft or ATS unit to suspend operation for any reason, it shall, if possible, so inform other stations concerned, giving the time at which it is expected that operation will be resumed. When operation is resumed, other stations concerned shall be so informed. When it is necessary to suspend operation beyond the time specified in the original notice, a revised time of resumption of operation shall, if possible, be transmitted at or near the time first specified.

SERA.14083   Radio communication failure procedures

• (a) When an aircraft is unable to comply with SERA.8035, point (a), the flight crew shall attempt to establish contact on the previous channel used and, if not successful, on another channel appropriate to the route. If these attempts fail, the flight crew shall attempt to establish communication with:
• (1) the appropriate air traffic services unit;
• (2) other air traffic services units; or
• (3) other aircraft, using all available means, including, inter alia, data link, satellite voice and mobile phones and, when successful, advise that contact on the assigned channel could not be established.

• (b) When an expected communication from an aircraft has not been received within a time period such that the occurrence of a communication failure is suspected, or when requested by other air traffic services units, the air traffic controller shall call the aircraft on the frequencies on which the aircraft is believed to be listening, and:
• (1) when providing surveillance service, the air traffic controller shall normally determine whether or not the aircraft’s receiver is functioning, and if successful, continue providing air traffic control service using SSR code/ADS-B transmission changes or IDENT transmissions to obtain acknowledgement of clearances issued to the aircraft;
• (2) if not successful, the air traffic control unit shall:
• (i) request other air traffic services units to render assistance by calling the aircraft and relaying messages, if necessary;
• (ii) request aircraft on the route to attempt to establish communication with the aircraft and relay messages, if necessary;
• (iii) initiate the notification to the aircraft operator, as soon as possible, of any failure in air-ground communication;
• (3) if the attempts described in points (2)(i) and (2)(ii) fail, blind transmission of air traffic control clearances shall not be made to aircraft, except at the specific request of the originator. Other messages should be transmitted by blind transmission on the frequencies on which the aircraft is believed to be listening.

• (c) When an aircraft is unable to comply with point SERA.8035(a) and the attempts described in point (a) of SERA.14083 to establish communications are not successful, the radio communication failure procedures described below shall be applied:
• (1) The aircraft, when forming part of the aerodrome traffic at a controlled aerodrome, shall keep a watch for instructions as may be issued by visual signals.
• (2) The aircraft shall set the transponder on Mode A Code 7600 and/or set the ADS-B transmitter to indicate the loss of air-ground communications and comply with the procedures described in points (3), (4), (5) and (6), as appropriate.
• (3) A VFR flight shall continue to fly in visual meteorological conditions, land at the nearest suitable aerodrome, and report its arrival by the most expeditious means to the appropriate air traffic services unit.
• (4) Except as provided for in point (5), an IFR flight shall:
• (i) maintain the last assigned speed and level, or minimum flight altitude if higher, for a period of 20 minutes following:
• (A) the aircraft’s failure to make a required report; or
• (B) the time the transponder is set to 7 600 and/or the appropriate ADS-B emergency and/or urgency mode is transmitted if surveillance service is provided, and thereafter adjust level and speed in accordance with the filed flight plan as amended by delay and modification messages to the filed flight plan;
• (ii) when being vectored or having been directed by ATC to proceed offset using area navigation (RNAV):
• (A) with a specified limit, continue to that limit, then rejoin the last received and acknowledged route, taking into consideration the applicable minimum flight altitude; or
• (B) without a specified limit, rejoin the last received and acknowledged route no later than the next significant point, taking into consideration the applicable minimum flight altitude;
• (iii) proceed according to the last received and acknowledged route clearance to the appropriate designated navigation aid or fix serving the destination aerodrome and, when required to ensure compliance with point (iv) below, hold over this aid or fix until commencement of descent;
• (iv) commence descent from the navigation aid or fix specified in point (iii) at, or as close as possible to, the expected approach time last received and acknowledged; or, if no expected approach time has been received and acknowledged, at, or as close as possible to, the estimated time of arrival;
• (v) complete an instrument approach procedure as specified for the designated navigation aid or fix; and
• (vi) land, if possible, within 30 minutes after the estimated time of arrival specified in point (iv) or the last acknowledged expected approach time, whichever is later.
• (5) An IFR flight following a standard instrument departure route or a standard instrument arrival route shall comply with the procedures for radio communication failure specified on the Standard Departure Chart – Instrument (SID) or Standard Arrival Chart – Instrument (STAR), when provided.
• (6) If an IFR flight encounters visual meteorological conditions and the pilot-in-command decides to continue to fly in visual meteorological conditions, the pilot shall set Mode A Code 7601, land at the nearest suitable aerodrome, and report arrival by the most expeditious means to the appropriate air traffic services unit.

• (d) The provision of air traffic control service to flights operating in the airspace concerned shall be based on the premise that an aircraft experiencing communication failure complies with point (c).

• (e) As soon as it is known that an aircraft operating in its area of responsibility is experiencing an apparent radio communication failure, an air traffic control unit shall forward information concerning the radio communication failure to all air traffic services units concerned along the route of flight. The area control centre in whose area the destination aerodrome is located shall take steps to obtain information on the alternate aerodrome(s) and other relevant information specified in the filed flight plan, if such information is not available.

• (f) When an air traffic control unit receives information that an aircraft, after experiencing a communication failure, has re-established communication or has landed, that unit shall inform the air traffic control unit in whose area the aircraft was operating at the time the failure occurred, and other air traffic services units concerned along the route of flight, giving necessary information for the continuation of control if the aircraft continues its flight.

- (g) The signals used in case of communication failure shall be in accordance with Appendix 1.

SERA.14085   Use of blind transmission

• (a) When an aircraft fails to establish contact on the designated channel, on the previous channel used or on another channel appropriate to the route, and fails to establish communication with the appropriate ATS unit, other ATS unit or other aircraft using all available means, the aircraft shall transmit its message twice on the designated channel(s), preceded by the phrase ‘TRANSMITTING BLIND’ and, if necessary, include the addressee(s) for which the message is intended.

- (b) When an aircraft is unable to establish communication due to receiver failure, it shall transmit reports at the scheduled times, or positions, on the channel in use preceded by the phrase ‘TRANSMITTING BLIND DUE TO RECEIVER FAILURE’. The aircraft shall:

• (1) transmit the intended message, following this by a complete repetition;
• (2) advise the time of its next intended transmission;
• (3) when provided with ATS, transmit information regarding the intention of the pilot-in-command with respect to the continuation of the flight.

SERA.14090   Specific communication procedures

• (a) Movement of vehicles Phraseologies for the movement of vehicles on the manoeuvring area shall be the same as those used for the movement of aircraft, with the exception of taxi instructions, in which case the word ‘PROCEED’ shall be substituted for the word ‘TAXI’ when communicating with vehicles.

• (b) Air traffic advisory service Air traffic advisory service does not deliver ‘clearances’ but only ‘advisory information’ and it shall use the word ‘advise’ or ‘suggest’ when a course of action is proposed to an aircraft.

• (c) Indication of heavy and super wake turbulence categories In the initial radiotelephony contact between such aircraft and ATS units the word ‘heavy’ or ‘super’ corresponding, as appropriate, to the wake turbulence category of the aircraft, shall be included immediately after the aircraft call sign.

• (d) Procedures related to weather deviation
• (1) When weather deviation is required, the pilot shall initiate communications with ATC via voice or CPDLC. A rapid response may be obtained by either:
• (i) stating ‘WEATHER DEVIATION REQUIRED’ to indicate that priority is desired on the frequency and for ATC response; or
• (ii) requesting a weather deviation using a CPDLC lateral downlink message.
• (2) When necessary, the pilot shall initiate communications using the urgency call ‘PAN PAN’ (preferably spoken three times) or by using a CPDLC urgency downlink message.
• (3) The pilot shall notify the air traffic controller and request clearance to deviate from track or ATS route, advising, when possible, the extent of the deviation requested. The flight crew will use whatever means are appropriate (i.e. voice and/or CPDLC) to communicate during a weather deviation.
• (4) The pilot shall inform the air traffic controller when weather deviation is no longer required, or when a weather deviation has been completed and the aircraft has returned to its cleared route.

- (e) Clearances on standard instrument departure and standard instrument arrival

Clearances on SID and/or STAR shall unambiguously indicate the constraints, where applicable.

SERA.14095   Distress and urgency radiotelephony communication procedures

• (a) General
• (1) Distress and urgency traffic shall comprise all radiotelephony messages relative to the distress and urgency conditions respectively. Distress and urgency conditions are defined as: (i) Distress : a condition of being threatened by serious and/or imminent danger and of requiring immediate assistance. (ii) Urgency : 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.
• (2) The radiotelephony distress signal ‘MAYDAY’ and the radiotelephony urgency signal ‘PAN PAN’ shall be used at the commencement of the first distress and urgency communication respectively. At the commencement of any subsequent communication in distress and urgency traffic, it shall be permissible to use the radiotelephony distress and urgency signals.
• (3) The originator of messages addressed to an aircraft in distress or urgency condition shall restrict to the minimum the number and volume and content of such messages as required by the condition.
• (4) If no acknowledgement of the distress or urgency message is made by the ATS unit addressed by the aircraft, other ATS units shall render assistance as prescribed in points (b)(2) and (b)(3) respectively.
• (5) Distress and urgency traffic shall normally be maintained on the frequency on which such traffic was initiated until it is considered that better assistance can be provided by transferring that traffic to another frequency.
• (6) In cases of distress and urgency communications, in general, the transmissions by radiotelephony shall be made slowly and distinctly, each word being clearly pronounced to facilitate transcription.

• (b) Radiotelephony distress communications
• (1) Action by the aircraft in distress In addition to being preceded by the radiotelephony distress signal ‘MAYDAY’ in accordance with point (a)(2), preferably spoken three times, the distress message to be sent by an aircraft in distress shall:
• (i) be on the air-ground frequency in use at the time;
• (ii) consist of as many as possible of the following elements spoken distinctly and, if possible, in the following order:
• (A) the name of the ATS unit addressed (time and circumstances permitting);
• (B) the identification of the aircraft;
• (C) the nature of the distress condition;
• (D) the intention of the pilot-in-command;
• (E) present position, level and heading.
• (2) Action by the ATS unit addressed or by the first ATS unit acknowledging the distress message The ATS unit addressed by an aircraft in distress, or the first ATS unit acknowledging the distress message, shall:
• (i) immediately acknowledge the distress message;
• (ii) take control of the communications or specifically and clearly transfer that responsibility, advising the aircraft if a transfer is made; and
• (iii) take immediate action to ensure that all necessary information is made available, as soon as possible, to:
• (A) the ATS unit concerned;
• (B) the aircraft operator concerned, or its representative, in accordance with pre-established arrangements;
• (iv) warn other ATS units, as appropriate, in order to prevent the transfer of traffic to the frequency of the distress communication.
• (3) Imposition of silence
• (i) The aircraft in distress, or the ATS unit in control of distress traffic, shall be permitted to impose silence, either on all stations of the mobile service in the area or on any station which interferes with the distress traffic. It shall address these instructions ‘to all stations’ or to one station only, according to the circumstances. In either case, it shall use:
• (A) ‘STOP TRANSMITTING’;
• (B) the radiotelephony distress signal ‘MAYDAY’.
• (ii) The use of the signals specified in point (b)(3)(i) shall be reserved for the aircraft in distress and for the ATS unit controlling the distress traffic.
• (4) Action by all other ATS units/aircraft
• (i) The distress communications have absolute priority over all other communications and ATS units/aircraft aware of them shall not transmit on the frequency concerned unless:
• (A) the distress is cancelled or the distress traffic is terminated;
• (B) all distress traffic has been transferred to other frequencies;
• (C) the ATS unit controlling communications gives permission;
• (D) it has itself to render assistance.
• (ii) Any ATS unit/aircraft which has knowledge of distress traffic, and which cannot itself assist the aircraft in distress, shall nevertheless continue listening to such traffic until it is evident that assistance is being provided.
• (5) Termination of distress communications and of silence
• (i) When an aircraft is no longer in distress, it shall transmit a message cancelling the distress condition.
• (ii) When the ATS unit which has controlled the distress communication traffic becomes aware that the distress condition is ended, it shall take immediate action to ensure that this information is made available, as soon as possible, to:
• (A) the ATS units concerned;
• (B) the aircraft operator concerned, or its representative, in accordance with pre-established arrangements.
• (iii) The distress communication and silence conditions shall be terminated by transmitting a message, including the words ‘DISTRESS TRAFFIC ENDED’, on the frequency or frequencies being used for the distress traffic. This message shall be originated only by the ATS unit controlling the communications when, after the reception of the message prescribed in point (b)(5)(i), it is authorised to do so by the competent authority.

• (c) Radiotelephony urgency communications
• (1) Action by the aircraft reporting an urgency condition except as indicated in point (c)(4) In addition to being preceded by the radiotelephony urgency signal ‘PAN PAN’ in accordance with point (a)(2), preferably spoken three times and each word of the group pronounced as the French word ‘panne’, the urgency message to be sent by an aircraft reporting an urgency condition shall:
• (i) be on the air-ground frequency in use at the time;
• (ii) consist of as many as required of the following elements spoken distinctly and, if possible, in the following order:
• (A) the name of the ATS unit addressed;
• (B) the identification of the aircraft;
• (C) the nature of the urgency condition;
• (D) the intention of the pilot-in-command;
• (E) present position, level and heading;
• (F) any other useful information.
• (2) Action by the ATS unit addressed or first ATS unit acknowledging the urgency message The ATS unit addressed by an aircraft reporting an urgency condition or the first ATS unit acknowledging the urgency message shall:
• (i) acknowledge the urgency message;
• (ii) take immediate action to ensure that all necessary information is made available, as soon as possible, to:
• (A) the ATS unit concerned;
• (B) the aircraft operator concerned, or its representative, in accordance with pre-established arrangements;
• (iii) if necessary, exercise control of communications.
• (3) Action by all other ATS units/aircraft The urgency communications have priority over all other communications except distress communications and all ATS units/aircraft shall take care not to interfere with the transmission of urgency traffic.
• (4) Action by an aircraft used for medical transports
• (i) The use of the signal described in point (c)(4)(ii) shall indicate that the message which follows concerns a protected medical transport pursuant to the 1949 Geneva Conventions and Additional Protocols.
• (ii) For the purpose of announcing and identifying aircraft used for medical transports, a transmission of the radiotelephony urgency signal ‘PAN PAN’, preferably spoken three times, and each word of the group pronounced as the French word ‘panne’, shall be followed by the radiotelephony signal for medical transports ‘MAY-DEE-CAL’, pronounced as in the French ‘medical’. The use of the signals described above indicates that the message which follows concerns a protected medical transport. The message shall convey the following data:
• (A) the call sign or other recognised means of identification of the medical transports;
• (B) position of the medical transports;
• (C) number and type of the medical transports;
• (D) intended route;
• (E) estimated time en-route and of departure and arrival, as appropriate; and
• (F) any other information such as flight altitude, radio frequencies guarded, languages used and secondary surveillance radar modes and codes.
• (5) Action by the ATS units addressed, or by other stations receiving a medical transports message The provisions of points (c)(2) and (c)(3) shall apply as appropriate to ATS units receiving a medical transports message.

- (d) As laid down in Article 4a the VHF emergency frequency (121,500 MHz) shall be used for genuine emergency purposes including any of the following:

• (1) to provide a clear channel between aircraft in distress or emergency and a ground station when the normal channels are being utilised for other aircraft;
• (2) to provide a VHF communication channel between aircraft and aerodromes, not normally used by international air services, in case of an emergency condition arising;
• (3) to provide a common VHF communication channel between aircraft, either civil or military, and between such aircraft and surface services, involved in common search and rescue operations, prior to changing when necessary to the appropriate frequency;
• (4) to provide air–ground communication with aircraft when airborne equipment failure prevents the use of the regular channels;
• (5) to provide a channel for the operation of emergency locator transmitters, and for communication between survival craft and aircraft engaged in search and rescue operations;
• (6) to provide a common VHF channel for communication between civil aircraft and intercepting aircraft or intercept control units and between civil or intercepting aircraft and air traffic services units in the event of interception of the civil aircraft.

SERA.14100   Notification of suspected communicable diseases or other public health risk on board an aircraft

• (a) The flight crew of an en-route aircraft shall, upon identifying a suspected case(s) of a communicable disease, or other public health risk, on board the aircraft, promptly notify the air traffic services unit with which the pilot is communicating, the information listed below:
• (1) aircraft identification;
• (2) departure aerodrome;
• (3) destination aerodrome;
• (4) estimated time of arrival;
• (5) number of persons on board;
• (6) number of suspected cases on board; and
• (7) nature of the public health risk, if known.

• (b) The air traffic services unit, upon receipt of information from a pilot regarding a suspected case(s) of a communicable disease, or other public health risk, on board the aircraft, shall forward a message as soon as possible to the air traffic services unit serving the destination/departure, unless procedures exist to notify the appropriate authority designated by the State and the aircraft operator or its designated representative.

- (c) When a report of a suspected case(s) of a communicable disease, or other public health risk, on board an aircraft is received by an air traffic services unit serving the destination/departure, from another air traffic services unit or from an aircraft or an aircraft operator, the unit concerned shall forward a message as soon as possible to the public health authority or the appropriate authority designated by the State as well as the aircraft operator or its designated representative, and the aerodrome operator.

SECTION 15

Controller–pilot data link communication (CPDLC) procedures

SERA.15001 Data link initiation and data link initiation failure