M1, S1, C11 - Traffic Information and Co-ordination Between ATS Personnel

Question 1

Traffic information passed between ATS personnel is…

Answer 1

…information about aircraft that is relevant to the provision of an air traffic service.

The purpose of traffic information is to enable the recipient to determine whether or not any action is necessary to achieve or maintain the required separation between the subject aircraft.

For example, after receiving traffic information, a controller may consider it necessary to issue avoiding action or may request co-ordination with respect to the traffic.

Question 2

The passing of traffic information does not imply…

Answer 2

…a commitment to an agreed course of action and there is no undertaking to update the information that has been passed.

The dynamic nature of an air traffic environment may render traffic information obsolete once passed but if, after receiving traffic information, a controller believes that co-ordination is necessary, he shall use the term “request co-ordination” and shall follow the verbal procedure detailed below.

Question 3

Co-ordination is…

Answer 3

…the act of negotiation between two or more parties each vested with the authority to make executive decisions appropriate to the task being discharged.

Co-ordination is effected when the parties concerned, on the basis of known intelligence, agree a course of action.

Responsibility for obtaining the agreement and for ensuring implementation of the agreed course of action may be vested in one of the controllers involved

Question 4

Controllers should be aware that co-ordination between the parties involved can be upon…

Answer 4

…aircraft that are either in receipt of, or about to be in receipt of, an air traffic service.

Question 5

A controller may carry out co-ordination on behalf of another controller, provided that…

Answer 5

…the traffic situation and time available are such that the controller being represented can put into effect any agreed actions

Question 6

Co-ordination may be achieved by one of the following methods:

Answer 6

(1) Tactical Co-ordination. The co-ordination of individual aircraft to which the co-ordinating controllers are providing, or are about to provide, an ATS. It is achieved either verbally (face-to-face or over a landline) or silently using an electronic data communications system. Silent co-ordination procedures are to be detailed in the MATS Part 2 and Unit Military Procedures.
(2) Standing Co-ordination. Co-ordination which is implemented automatically, on a permanent basis, without communication between the controllers involved. It is effected in accordance with a written agreement between the units or sectors involved, and is only valid for the aircraft and circumstances specified in the MATS Part 2.

Question 7

When approved by the CAA, co-ordination is deemed to have been achieved if…

Answer 7

…an estimate message has been passed and the accepting ATC unit has raised no objection.

Question 8

When requesting co-ordination, a controller shall:

Answer 8

(1) make verbal contact with the appropriate controller and, after identifying himself, open the dialogue with the words “Request Co-ordination”;
(2) refer to his aircraft and the aircraft upon which co-ordination is requested in the order most appropriate to the situation;
(3) propose a course of action upon which agreement is requested and obtain a clear decision on that proposal. To ensure clarity and avoid misunderstandings, before terminating the call, parties shall explicitly state the action required of their aircraft to achieve the agreed course of action. For example, an appropriate response to a request for an aircraft to maintain FL120 may be, “My traffic maintaining FL120”. A response that does not reaffirm the details of the agreement, such as “Roger”, is not acceptable.

Question 9

When co-ordinating aircraft that are or are about to be operating within RVSM designated airspace…

Answer 9

…the RVSM approval status of the individual aircraft involved shall be included in the co-ordination message, unless the status is known to be self-evident to both controllers.

Question 10

The proposed course of action to achieve separation must be expressed in…

Answer 10

…unambiguous terms.

A statement that no action will be taken can constitute an agreement, although there is still a requirement for both controllers to state explicitly the actions required of their aircraft.

Question 11

Great care must be taken when co-ordinating aircraft that are…

Answer 11

…climbing or descending, or are expecting further climb or descent, to ensure that accurate information is given and that any agreement takes account of the actual or proposed flight profile and/or cleared level.

Question 12

Where aircraft are climbing or descending, controllers may include the provision of…

Answer 12

…horizontal separation until a flight profile is achieved that will provide adequate vertical separation with the conflicting traffic.

For example, “I will take 5 miles until above FL210”, or, “I will take 5 miles until 1000 ft above/below on Charlie”.

In the absence of an RT report from the pilot of passing or reaching the required level, the criteria for level assessment of Mode C shall be applied.

Where combinations of horizontal and vertical separation are used in co-ordinating aircraft, controllers shall closely monitor aircraft tracks and levels to ensure that standard horizontal separation is maintained until the requisite vertical separation exists.

Question 13

Where both aircraft are climbing, or both are descending, controllers may co-ordinate to use…

Answer 13

…Mode C indications to enable an expeditious step climb/descent, which maintains the required vertical separation/ deconfliction minima,

e.g. “I will take 1000 ft above/below on Charlie”, or, “I will maintain 1000ft above/below on Charlie”.

In such circumstances the criteria for level assessment of Mode C shall be applied.

Question 14

For IFR/VFR flights within Class F/G airspace, controllers are individually responsible for deciding whether they need…

Answer 14

…tactical co-ordination, and to initiate such requests as appropriate. Therefore, unless specified in MATS Part 2, controllers should not rely on other controllers to initiate tactical co-ordination.

Question 15

Deconfliction Service or Procedural Service.

Unless safety is likely to be compromised, a pilot receiving a Deconfliction Service or Procedural Service shall not…

Answer 15

…change heading/track or level without first obtaining approval from the controller.

Consequently, such aircraft may be co-ordinated in both the lateral and vertical planes without the need for prior recourse to the pilot.

Question 16

Traffic Service.

Unless safety is likely to be compromised, a pilot receiving a Traffic Service shall not…

Answer 16

…change level, route, manoeuvring area, or deviate from an ATC heading without first advising and obtaining a response from the controller.

Consequently, such aircraft may be co-ordinated in the vertical plane, and in the lateral plane for those aircraft that have been allocated an ATC heading, without recourse to the pilot.

For manoeuvring aircraft and aircraft following a route, co-ordination in the lateral plane may take place subject to the controller agreeing with the pilot the precise horizontal limits of the aircraft’s manoeuvres.

Question 17

Basic Service.

Unless the pilot has entered into an agreement with a controller to maintain a specific course of action, a pilot receiving a Basic Service may change level, heading, or route without advising the controller.

Consequently, prior to such aircraft being coordinated in either the vertical or lateral planes, the following conditions shall be met:

Answer 17

(1) The aircraft receiving the Basic Service is subject to identification, and it is expected that identity will be maintained throughout the period during which co- ordination is requested.
(2) The pilot receiving a Basic Service agrees to maintain the required vertical or lateral profile for the required period or distance.
(3) For manoeuvring aircraft and aircraft following a route, co-ordination in the lateral plane may take place subject to the controller agreeing with the pilot the precise horizontal limits of the aircraft’s manoeuvres.

Question 18

Aircraft receiving an ATS from an ATC unit must not be permitted to…

Answer 18

…penetrate the airspace of another unit unless prior co-ordination has taken place.

The responsibility for initiating co-ordination rests with the controller of the unit transferring control. The transferring controller must comply with any conditions specified by the accepting controller.

Certain CAA approved units are permitted to operate within controlled airspace without prior co-ordination

Question 19

If the first reporting point after take-off is in the adjoining area…

Answer 19

…an approval request must be made to that ACC and co-ordination achieved before clearance is given to the aircraft unless the requirement has been waived by the CAA.