Regulation (EU) No 923/2012
Air traffic control service shall be provided:
(a) to all IFR flights in airspace Classes A, B, C, D and E;
(b) to all VFR flights in airspace Classes B, C and D;
(c) to all special VFR flights;
(d) to all aerodrome traffic at controlled aerodromes.
SERA.8005 Operation of air traffic control service
Regulation (EU) 2020/469
(a) In order to provide air traffic control service, an air traffic control unit shall:
(1) be provided with information on the intended movement of each aircraft, or variations therefrom, and with current information on the actual progress of each aircraft;
(2) determine from the information received, the relative positions of known aircraft to each other;
(3) issue one or more of the following: clearances, instructions or information for the purpose of preventing collision between aircraft under its control and of expediting and maintaining an orderly flow of traffic;
(4) coordinate clearances as necessary with other units:
(i) whenever an aircraft might otherwise conflict with traffic operated under the control of such other units;
(ii) before transferring control of an aircraft to such other units.
(b) Clearances issued by air traffic control units shall provide separation:
(1) between all flights in airspace Classes A and B;
(2) between IFR flights in airspace Classes C, D and E;
(3) between IFR flights and VFR flights in airspace Class C;
(4) between IFR flights and special VFR flights;
(5) between special VFR flights unless otherwise prescribed by the competent authority;
except that, when requested by the pilot of an aircraft and agreed by the pilot of the other aircraft and if so prescribed by the competent authority for the cases listed under b) above in airspace Classes D and E, a flight may be cleared subject to maintaining own separation in respect of a specific portion of the flight below 3 050 m (10 000 ft) during climb or descent, during day in visual meteorological conditions.
(c) Except for cases of operations on parallel or near-parallel runways as in point ATS.TR.255 of Annex IV to Commission Implementing Regulation (EU) 2017/37310 Commission Implementing Regulation (EU) 2017/373 of 1 March 2017 laying down common requirements for providers of air traffic management/air navigation services and other air traffic management network functions and their oversight, repealing Regulation (EC) No 482/2008, Implementing Regulations (EU) No 1034/2011, (EU) No 1035/2011 and (EU) 2016/1377 and amending Regulation (EU) No 677/2011 (OJ L 62, 8.3.2017, p. 1)., or when a reduction in separation minima in the vicinity of aerodromes can be applied, separation by an ATC unit shall be obtained by at least one of the following:
(1) vertical separation, obtained by assigning different levels selected from the table of cruising levels in Appendix 3, except that the correlation of levels to track as prescribed therein shall not apply whenever otherwise indicated in appropriate aeronautical information publications or ATC clearances. The vertical separation minimum shall be a nominal 300 m (1 000 ft) up to and including FL 410 and a nominal 600 m (2 000 ft) above that level. Geometric height information shall not be used to establish vertical separation;
(2) horizontal separation, obtained by providing:
(i) longitudinal separation, by maintaining an interval between aircraft operating along the same, converging or reciprocal tracks, expressed in time or distance; or
(ii) lateral separation, by maintaining aircraft on different routes or in different geographical areas.
GM1 SERA.8005(a)(3) Operation of air traffic control service
ED Decision 2020/007/R
CLEARANCE FOR IMMEDIATE TAKE-OFF
In the interest of expediting traffic, a clearance for immediate take-off may be issued to an aircraft before it enters the runway. On acceptance of such clearance, the aircraft should taxi out to the runway and take off in one continuous movement.
GM1 SERA.8005(b) Operation of air traffic control service
ED Decision 2013/013/R
CLEARANCES TO MAINTAIN OWN SEPARATION
Clearances for a pilot to maintain own separation in respect of a specific portion of the flight in airspace Classes D and E below 3 050 m (10 000 ft) during climb or descent, during day in visual meteorological conditions are based on the fact that in those airspace classes a speed restriction of 250 kt is applied to all flights, allowing pilots of both aircraft to observe other flights in time to avoid collision.
GM2 SERA.8005(b) Operation of air traffic control service
ED Decision 2020/007/R
CLEARANCES TO FLY MAINTAINING OWN SEPARATION WHILE IN VISUAL METEOROLOGICAL CONDITIONS
(a) If there is a possibility that flight under visual meteorological conditions may become impracticable, an IFR flight should be provided with alternative instructions to be complied with in the event that flight in visual meteorological conditions cannot be maintained for the term of the clearance.
(b) The pilot of an IFR flight, on observing that conditions are deteriorating and considering that operation in visual meteorological conditions will become impossible, should inform air traffic control units before entering instrument meteorological conditions and should proceed in accordance with the alternative instructions given.
GM3 SERA.8005(b) Operation of air traffic control service
ED Decision 2020/007/R
CLEARANCES TO FLY MAINTAINING OWN SEPARATION WHILE IN VISUAL METEOROLOGICAL CONDITIONS
(a) The provision of vertical or horizontal separation by an air traffic control unit is not applicable in respect of any specified portion of a flight cleared subject to maintaining own separation and remaining in visual meteorological conditions. It is for the aircraft so cleared to ensure, for the duration of the clearance, that it is not operated in such proximity to other flights as to create a collision hazard.
(b) It is axiomatic that a VFR flight must remain in visual meteorological conditions at all times. Accordingly, the issuance of a clearance to a VFR flight to fly subject to maintaining own separation and remaining in visual meteorological conditions has no other object than to signify that, for the duration of the clearance, separation from other aircraft by air traffic control units is not provided.
(c) The objectives of the air traffic control service as prescribed in ATS.TR.100 of Regulation (EU) 2017/373 do not include prevention of collision with terrain. Pilots are responsible for ensuring that any clearances issued by air traffic control units are safe in this respect. When vectoring or assigning a direct routing not included in the flight plan, which takes an IFR flight off published ATS route or instrument procedure, the procedures in ATS.TR.235(a)(5) of Regulation (EU) 2017/373 apply.
AMC1 SERA.8005(c) Operation of air traffic control service
ED Decision 2020/007/R
VISUAL APPROACH
(a) Subject to the conditions described in point (b), clearance for an IFR flight to execute a visual approach may be requested by a flight crew or initiated by the air traffic controller. In the latter case, the concurrence of the flight crew should be required.
(b) An IFR flight should only be cleared to execute a visual approach, provided the pilot can maintain visual reference to the terrain and:
(1) the reported ceiling is at or above the level of the beginning of the initial approach segment for the aircraft so cleared; or
(2) the pilot reports at the level of the beginning of the initial approach segment or at any time during the instrument approach procedure that the meteorological conditions are such that with reasonable assurance a visual approach and landing can be completed.
(c) Except between aircraft performing successive visual approaches as described in point (d), separation should be provided between an aircraft cleared to execute a visual approach and other arriving and departing aircraft.
(d) For successive visual approaches, separation should be maintained by the air traffic controller until the pilot of a succeeding aircraft reports having the preceding aircraft in sight. The aircraft should then be instructed to follow and maintain own separation from the preceding aircraft.
(e) In case of aircraft performing successive visual approaches and instructed to maintain own separation as in point (d), and the distance between such aircraft is less than the appropriate wake turbulence minimum, the air traffic controller should issue a caution of possible wake turbulence.
GM1 to AMC1 SERA.8005(c) Operation of air traffic control service
ED Decision 2020/007/R
VISUAL APPROACH
The pilot-in-command of the aircraft concerned is responsible for ensuring that the spacing from a preceding aircraft of a heavier wake turbulence category is acceptable. If it is determined that additional spacing is required, the flight crew should inform the ATC unit accordingly, stating their requirements.
GM1 SERA.8005(c)(1) Operation of air traffic control service
ED Decision 2020/007/R
GEOMETRIC HEIGHT INFORMATION
Geometric height information is generated by airborne systems such as GPS or radio altimeters.
Regulation (EU) No 923/2012
(a) The selection of separation minima for application within a given portion of airspace shall be made by the ANSP responsible for the provision of air traffic services and approved by the competent authority concerned.
(b) For traffic that will pass from one into the other of neighbouring airspaces and for routes that are closer to the common boundary of the neighbouring airspaces than the separation minima applicable in the circumstances, the selection of separation minima shall be made in consultation between the ANSPs responsible for the provision of air traffic services in neighbouring airspace.
(c) Details of the selected separation minima and of their areas of application shall be notified:
(1) to the air traffic services units concerned; and
(2) to pilots and aircraft operators through aeronautical information publications, where separation is based on the use by aircraft of specified navigation aids or specified navigation techniques.
GM1 SERA.8010(b) Separation minima
ED Decision 2013/013/R
GENERAL
The purpose of this provision is to ensure, in the first case, compatibility on both sides of the line of transfer of traffic and, in the other case, adequate separation between aircraft operating on both sides of the common boundary.
SERA.8012 Application of wake turbulence separation
Regulation (EU) 2020/469
(a) Air traffic control units shall apply wake turbulence separation minima to aircraft in the approach and departure phases of flight in any of the following circumstances:
(1) an aircraft is operating directly behind another aircraft at the same altitude or less than 300 m (1 000 ft) below it;
(2) both aircraft are using the same runway or parallel runways separated by less than 760 m (2 500 ft);
(3) an aircraft is crossing behind another aircraft at the same altitude or less than 300 m (1 000 ft) below it.
(b) Paragraph (a) shall not apply to arriving VFR flights and to arriving IFR flights executing visual approach when the aircraft has reported the preceding aircraft in sight and has been instructed to follow and maintain own separation from that aircraft. In those cases, the air traffic control unit shall issue caution for wake turbulence.
SERA.8015 Air traffic control clearances
Regulation (EU) 2020/469
(a) Air traffic control clearances shall be based solely on the following requirements for providing air traffic control service:
(1) Clearances shall be issued solely for expediting and separating air traffic and be based on known traffic conditions which affect safety in aircraft operation. Such traffic conditions include not only aircraft in the air and on the manoeuvring area over which control is being exercised, but also any vehicular traffic or other obstructions not permanently installed on the manoeuvring area in use.
(2) ATC units shall issue such ATC clearances as necessary to prevent collisions and to expedite and maintain an orderly flow of air traffic.
(3) ATC clearances shall be issued early enough to ensure that they are transmitted to the aircraft in sufficient time for it to comply with them.
(b) Operation subject to clearance
(1) An air traffic control clearance shall be obtained prior to operating a controlled flight, or a portion of a flight as a controlled flight. Such clearance shall be requested through the submission of a flight plan to an air traffic control unit.
(2) The pilot-in-command of an aircraft shall inform ATC if an air traffic control clearance is not satisfactory. In such cases, ATC will issue an amended clearance, if practicable.
(3) Whenever an aircraft has requested a clearance involving priority, a report explaining the necessity for such priority shall be submitted, if requested by the appropriate air traffic control unit.
(4) Potential reclearance in flight. If, prior to departure, it is anticipated that, depending on fuel endurance and subject to reclearance in flight, a decision may be taken to proceed to a revised destination aerodrome, the appropriate air traffic control units shall be so notified by the insertion in the flight plan of information concerning the revised route (where known) and the revised destination.
(5) An aircraft operated on a controlled aerodrome shall not taxi on the manoeuvring area without clearance from the aerodrome control tower and shall comply with any instructions given by that unit.
(6) When vectoring or assigning a direct routing not included in the flight plan, which takes an IFR flight off published ATS route or instrument procedure, an air traffic controller providing ATS surveillance service shall issue clearances such that the prescribed obstacle clearance exists at all times until the aircraft reaches the point where the pilot re-joins the flight plan route or joins a published ATS route or instrument procedure.
(c) Clearances for transonic flight
(1) The air traffic control clearance relating to the transonic acceleration phase of a supersonic flight shall extend at least to the end of that phase.
(2) The air traffic control clearance relating to the deceleration and descent of an aircraft from supersonic cruise to subsonic flight shall seek to provide for uninterrupted descent at least during the transonic phase.
(d) Contents of clearances
An air traffic control clearance shall indicate:
(1) aircraft identification as shown in the flight plan;
(2) clearance limit;
(3) route of flight, …
(i) the route of flight shall be detailed in each clearance when deemed necessary; and
(ii) the phrase ‘cleared via flight planned route’ shall not be used when granting a re-clearance;
(4) level(s) of flight for the entire route or part thereof and changes of levels if required;
(5) any necessary instructions or information on other matters, such as ATFM departure slot if applicable, approach or departure manoeuvres, communications and the time of expiry of the clearance.
(e) Read back of clearances, instructions and safety-related information
(1) The flight crew shall read back to the air traffic controller safety-related parts of ATC clearances and instructions which are transmitted by voice. The following items shall always be read back:
(i) ATC route clearances;
(ii) clearances and instructions to enter, land on, take off from, hold short of, cross, taxi and backtrack on any runway; and
(iii) runway-in-use, altimeter settings, SSR codes, newly assigned communication channels, level instructions, heading and speed instructions; and
(iv) transition levels, whether issued by the controller or contained in ATIS broadcasts.
(2) Other clearances or instructions, including conditional clearances and taxi instructions, shall be read back or acknowledged in a manner to clearly indicate that they have been understood and will be complied with.
(3) The controller shall listen to the read-back to ascertain that the clearance or instruction has been correctly acknowledged by the flight crew and shall take immediate action to correct any discrepancies revealed by the read-back.
(4) Voice read-back of CPDLC messages shall not be required, unless otherwise specified by the ANSP.
(ea) Changes in clearance regarding route or level
(1) When issuing a clearance covering a requested change in route or level, the exact nature of the change shall be included in the clearance.
(2) When traffic conditions will not permit clearance of a requested change, the word ‘UNABLE’ shall be used. When warranted by circumstances, an alternative route or level shall be offered.
(eb) Clearance related to altimetry
(1) For flights in areas where a transition altitude is established, the vertical position of the aircraft shall, except as provided for in (5) below, be expressed in terms of altitudes at or below the transition altitude and in terms of flight levels at or above the transition level. While passing through the transition layer, the vertical position shall be expressed in terms of flight levels when climbing and in terms of altitudes when descending.
(2) The flight crew shall be provided with the transition level in due time prior to reaching it during descent.
(3) Except when it is known that the aircraft has already received the information in a directed transmission, an QNH altimeter setting shall be included in:
(i) the descent clearance, when first cleared to an altitude below the transition level;
(ii) the approach clearance or the clearance to enter the traffic circuit;
(iii) the taxi clearance for departing aircraft.
(4) A QFE altimeter setting shall be provided to aircraft on request or on a regular basis in accordance with local arrangements.
(5) When an aircraft has been given clearance to land or where an aircraft has been informed that the runway is available for landing at AFIS aerodromes and that aircraft is completing its approach using atmospheric pressure at aerodrome elevation (QFE), the vertical position of that aircraft shall be expressed in terms of height above aerodrome elevation during that portion of its flight for which QFE may be used, except that it shall be expressed in terms of height above runway threshold elevation:
(i) for instrument runways if the threshold is 2 m (7 ft) or more below the aerodrome elevation; and
(ii) for precision approach runways.
(ec) Conditional clearances
Conditional phrases, such as ‘behind landing aircraft’ or ‘after departing aircraft’, shall not be used for movements affecting the active runway(s), except when the aircraft or vehicles concerned are seen by the appropriate controller and pilot. The aircraft or vehicle causing the condition in the clearance issued shall be the first aircraft/vehicle to pass in front of the other aircraft concerned. In all cases, a conditional clearance shall be given in the following order and consist of:
(1) the call sign;
(2) the condition;
(3) the clearance; and
(4) a brief reiteration of the condition.
(f) Coordination of clearances
(1) An air traffic control clearance shall be coordinated between air traffic control units to cover the entire route of an aircraft or a specified portion thereof as described in provisions (2) to (6).
(2) An aircraft shall be cleared for the entire route to the aerodrome of first intended landing:
(i) when it has been possible, prior to departure, to coordinate the clearance between all the units under whose control the aircraft will come; or
(ii) when there is reasonable assurance that prior coordination will be effected between those units under whose control the aircraft will subsequently come.
(3) When coordination as in (2) has not been achieved or is not anticipated, the aircraft shall be cleared only to that point where coordination is reasonably assured; prior to reaching such point, or at such point, the aircraft shall receive further clearance, holding instructions being issued as appropriate.
(4) When prescribed by the ATS unit, aircraft shall contact a downstream air traffic control unit, for the purpose of receiving a downstream clearance prior to the transfer of control point.
(i) Aircraft shall maintain the necessary two-way communication with the current air traffic control unit whilst obtaining a downstream clearance.
(ii) A clearance issued as a downstream clearance shall be clearly identifiable as such to the pilot.
(iii) Unless coordinated, downstream clearances shall not affect the aircraft’s original flight profile in any airspace, other than that of the air traffic control unit responsible for the delivery of the downstream clearance.
(5) When an aircraft intends to depart from an aerodrome within a control area to enter another control area within a period of thirty minutes, or such other specific period of time as has been agreed between the area control centres concerned, coordination with the subsequent area control centre shall be effected prior to issuance of the departure clearance.
(6) When an aircraft intends to leave a control area for flight outside controlled airspace, and will subsequently re-enter the same or another control area, a clearance from the point of departure to the aerodrome of first intended landing may be issued. Such clearance or revisions thereto shall apply only to those portions of the flight conducted within controlled airspace.
GM1 SERA.8015(a) Air traffic control clearances
ED Decision 2016/023/R
Clearances to VFR flights in airspace classes C and D do not imply any form of separation:
(a) in Class C — between VFR flights; and
(b) in Class D — between IFR and VFR flights or between VFR flights.
For the case of special VFR flights, refer to SERA.8005(b).
GM1 SERA.8015(b)(4) Air traffic control clearances
ED Decision 2013/013/R
OPERATION SUBJECT TO CLEARANCE — POTENTIAL RECLEARANCE IN FLIGHT
The intent of the provision relating to potential reclearance is to facilitate reclearance to a revised destination, normally beyond the filed destination aerodrome.
GM1 SERA.8015(d)(5) Air traffic control clearances
ED Decision 2013/013/R
CONTENT OF THE CLEARANCES — TIME OF EXPIRY
The time of expiry of the clearance indicates the time after which the clearance will be automatically cancelled if the flight has not been commenced.
GM1 SERA.8015(e)(1) ATC clearances
ED Decision 2020/007/R
CHANGE IN CLEARANCE REGARDING THE ROUTE
The nature of the change should include a description of the route and levels to the point where it joins the previously cleared route, or, if the aircraft will not rejoin the previous route, to the destination.
GM1 SERA.8015(e)(4) Air traffic control clearances
ED Decision 2013/013/R
READ-BACK OF CPDLC MESSAGES
When so indicated by local safety assessments, ANSP may require that the receipt of some of the CPDLC message types (in particular those addressing trajectory changes) be acknowledged by voice.
GM1 SERA.8015(f)(2) Air traffic control clearances
ED Decision 2016/023/R
PROVISIONS FOR CLEARANCES AND INSTRUCTIONS — ALTIMETRY
The provision of transition level may be accomplished by voice communications, ATIS broadcast or data link.
GM1 SERA.8015(f)(4) Air traffic control clearances
ED Decision 2013/013/R
COORDINATION OF CLEARANCES — DOWNSTREAM CLEARANCE
(a) In such cases it is assumed that contact of a downstream ATC unit is initiated by the pilot. Therefore, the rules require that the aircraft maintain the necessary two-way communication with the current ATC unit.
(b) In cases where an aircraft cannot maintain two-way communication whilst obtaining a downstream clearance, the pilot needs to seek the acceptance to leave momentarily the communication channel of the current ATC unit prior to contacting a downstream ATC unit.
GM1 SERA.8015(g) Air traffic control clearances
ED Decision 2016/023/R
CONDITIONAL CLEARANCES
An example of a conditional clearance is ‘SCANDINAVIAN 941, BEHIND DC9 ON SHORT FINAL, LINE UP BEHIND’. This implies the need for the aircraft receiving the conditional clearance to identify the aircraft or vehicle causing the conditional clearance.
SERA.8020 Adherence to flight plan
Regulation (EU) 2016/1185
(a) Except as provided for in (b) and (d) an aircraft shall adhere to the current flight plan or the applicable portion of a current flight plan submitted for a controlled flight unless a request for a change has been made and clearance obtained from the appropriate air traffic control unit, or unless an emergency situation arises which necessitates immediate action by the aircraft, in which event as soon as circumstances permit, after such emergency authority is exercised, the appropriate air traffic services unit shall be notified of the action taken and that this action has been taken under emergency authority.
(1) Unless otherwise authorised by the competent authority, or directed by the appropriate air traffic control unit, controlled flights shall, in so far as practicable:
(i) when on an established ATS route, operate along the defined centre line of that route; or
(ii) when on any other route, operate directly between the navigation facilities and/or points defining that route.
(2) Unless otherwise authorised by the competent authority, or directed by the appropriate air traffic control unit, an aircraft operating along an ATS route segment defined by reference to very high frequency omnidirectional radio ranges shall change over for its primary navigation guidance from the facility behind the aircraft to that ahead of it at, or as close as operationally feasible to, the changeover point, where established.
(3) Deviation from the requirements in point (1) shall be notified to the appropriate ATS unit.
(b) Inadvertent changes. In the event that a controlled flight inadvertently deviates from its current flight plan, the following action shall be taken:
(1) Deviation from track: if the aircraft is off track, action shall be taken forthwith to adjust the heading of the aircraft to regain track as soon as practicable.
(2) Variation in true airspeed: if the average true airspeed at cruising level between reporting points varies or is expected to vary by plus or minus 5 per cent of the true airspeed, from that given in the flight plan, the appropriate air traffic services unit shall be so informed.
(3) Change in time estimate: if the time estimate for the next applicable reporting point, flight information region boundary or destination aerodrome, whichever comes first, is found to be in error in excess of 2 minutes from that notified to ATS or such other period of time as prescribed by the competent authority, a revised estimated time shall be notified as soon as possible to the appropriate ATS unit.
(4) Additionally, when an ADS-C agreement is in place, the air traffic services unit shall be informed automatically via data link whenever changes occur beyond the threshold values stipulated by the ADS-C event contract.
(c) Intended changes. Requests for flight plan changes shall include information as indicated hereunder:
(1) Change of cruising level: aircraft identification; requested new cruising level and cruising speed at this level, revised time estimates (when applicable) at subsequent flight information region boundaries.
(2) Change of route:
(i) Destination unchanged: aircraft identification; flight rules; description of new route of flight including related flight plan data beginning with the position from which requested change of route is to commence; revised time estimates; any other pertinent information.
(ii) Destination changed: aircraft identification; flight rules; description of revised route of flight to revised destination aerodrome including related flight plan data, beginning with the position from which requested change of route is to commence; revised time estimates; alternate aerodrome(s); any other pertinent information.
(d) Weather deterioration below the VMC. When it becomes evident that flight in VMC in accordance with its current flight plan will not be practicable, a VFR flight operated as a controlled flight shall:
(1) request an amended clearance enabling the aircraft to continue in VMC to destination or to an alternative aerodrome, or to leave the airspace within which an ATC clearance is required; or
(2) if no clearance in accordance with a) can be obtained, continue to operate in VMC and notify the appropriate ATC unit of the action being taken either to leave the airspace concerned or to land at the nearest suitable aerodrome; or
(3) if operated within a control zone, request authorisation to operate as a special VFR flight; or
(4) request clearance to operate in accordance with the instrument flight rules.
Regulation (EU) 2016/1185
(a) Unless exempted by the competent authority or by the appropriate air traffic services unit under conditions specified by that authority, a controlled flight shall report to the appropriate air traffic services unit, as soon as possible, the time and level of passing each designated compulsory reporting point, together with any other required information. Position reports shall similarly be made in relation to additional points when requested by the appropriate air traffic services unit. In the absence of designated reporting points, position reports shall be made at intervals prescribed by the competent authority or specified by the appropriate air traffic services unit.
(1) Controlled flights providing position information to the appropriate air traffic services unit via data link communications shall only provide voice position reports when requested.
(2) When a controlled flight has been exempted from the requirement to report at compulsory reporting points, pilots shall, unless automated position reporting is in effect, resume voice or CPDLC position reporting:
(i) when so instructed;
(ii) when advised that the ATS surveillance service has been terminated; or
(iii) when advised that the ATS surveillance identification is lost.
(3) The format of position reports shall be in accordance with Appendix 5, Point A.
GM1 SERA.8025(a)(2) Position reports
ED Decision 2016/023/R
RESUMPTION OF CPDLC POSITION REPORTING
The resumption of controller–pilot data link communications (CPDLC) position reporting can be achieved through automatic dependent surveillance — contract (ADS-C).
SERA.8030 Termination of control
Regulation (EU) No 923/2012
A controlled flight shall, except when landing at a controlled aerodrome, advise the appropriate ATC unit as soon as it ceases to be subject to air traffic control service.
Regulation (EU) 2016/1185
(a) An aircraft operated as a controlled flight shall maintain continuous air-ground voice communication watch on the appropriate communication channel of, and establish two-way communication as necessary with, the appropriate air traffic control unit, except as may be prescribed by the relevant ANSP in respect of aircraft forming part of aerodrome traffic at a controlled aerodrome.
(1) The requirement for an aircraft to maintain an air-ground voice communication watch shall remain in effect when CPDLC has been established.
(b) The Member States shall comply with the appropriate provisions on communication failures as have been adopted under the Chicago Convention. The Commission shall take the necessary measures for the transposition of those provisions into Union law so as to establish common European procedures on communication failures by 31 December 2017 at the latest.
GM1 SERA.8035(a) Communications
ED Decision 2013/013/R
GENERAL
(a) In a HF environment, SELCAL or similar automatic signalling devices satisfy the requirement to maintain an air-ground voice communication watch.
(b) An aircraft may be permitted to communicate temporarily with a control unit other than the unit controlling the aircraft.
ED Decision 2016/023/R
ESTABLISHMENT OF PILOT–CONTROLLER COMMUNICATIONS
Direct pilot–controller communications should be established prior to the provision of ATS surveillance services unless special circumstances, such as emergencies, dictate otherwise.
ED Decision 2016/023/R
ACKNOWLEDGEMENT OF MESSAGES
(a) When a CPDLC emergency message is received, the controller shall acknowledge receipt of the message by the most efficient means available.
(b) Except as provided by (a), when a controller or pilot communicates via CPDLC, the response should be via CPDLC. When a controller or pilot communicates via voice, the response should be via voice.