M1, S3, C2 - Approach Radar

Question 1

The area within which Approach Radar Services are provided by an Approach Radar Control unit is determined by a number of factors, including…

Answer 1

…the coverage of ATS surveillance systems and requires approval by the CAA

Question 2

The service provided depends on the type of airspace within which the aircraft is operating as described below:

Answer 2

(1) Within controlled airspace – Radar Control Service;

(2) Outside controlled airspace – Procedural Service, Deconfliction Service, Traffic Service, or Basic Service.

Question 3

The extent of the ATS surveillance service which an Approach Radar Control unit may provide will depend on the type of ATS surveillance system and the operational procedures that have been approved by the CAA.

These are described in MATS Part 2 and may include:

Answer 3

(1) Surveillance Radar Approaches;
(2) Vectoring/sequencing to a pilot interpreted final approach aid;
(3) Flightpath monitoring of approaches utilising a pilot interpreted final approach aid;
(4) ATS surveillance services to departing aircraft;
(5) ATS surveillance services to transit aircraft, through an area for which Approach Radar Control is responsible.

Question 4

Certain ATS surveillance systems are not suitable for providing separation to other aircraft when…

Answer 4

…radar approaches are being given

Question 5

Approach radar controllers may be required to co-ordinate flights directly with…

Answer 5

…Aerodrome Control and Area Control units.

Detailed co-ordination procedures are described in MATS Part 2

Question 6

An approach radar controller shall not take control of an inbound aircraft unless:

Answer 6

(1) it has been transferred to him by the approach controller; or
(2) it is the subject of a ‘radar release’ from Area Control.

Question 7

As early as practicable in the procedure, the approach radar controller shall transmit the latest…

Answer 7

…weather observations to aircraft on radar approaches, except when this information has already been passed by Approach/Aerodrome Control, or the pilot indicates that he has received it from the ATIS broadcast.

Whilst the aircraft remains under the jurisdiction of the approach radar controller any revised or additional information must be passed to the pilot.

Question 8

Before commencing final approach, aircraft are to be given…

Answer 8

…the QNH.

Aerodrome and threshold elevations shall be available on request

Question 9

QFE may be given…

Answer 9

At the pilot’s request or if local procedures require

Question 10

Obstacle clearance criteria for all types of radar approaches, applicable to each runway on which radar approaches are used, are detailed…

Answer 10

…on aerodrome approach charts.

Question 11

Pilots using altitude will carry out their own conversion to…

Answer 11

…obtain an obstacle clearance altitude.

Question 12

The position of an aircraft is to be passed to the pilot…

Answer 12

…at least once on each leg of the circuit.

Question 13

Position information for an aircraft making a straight-in approach is to be passed…

Answer 13

…at least once before it commences the final descent

Question 14

Range marks on extended runway centrelines usually indicate distance from touchdown but range rings almost always indicate…

Answer 14

…distance from the position of the radar aerial head.

Question 15

Subject to an SI:

Prior to or upon commencement of vectoring to final approach the pilot is to be advised that the aircraft will be vectored to intercept the final approach and of:

Answer 15

(1) the type of final approach;
(2) the runway in use; and
(3) the procedure to be followed in the event of a radio communications failure if this is not published.

Question 16

Aircraft receiving an SRA shall be given:

Answer 16

(1) the angle of the nominal descent path or the recommended descent gradient;
(2) the termination range.

This may be achieved by using the published standard phraseology for SRA.

Question 17

Terrain clearance is to be applied in accordance with…

Answer 17

…MATS 1, Section 1, Chapter 6.

Question 18

SMAC are published in the UK AIP.

They indicate the…

Answer 18

…minimum altitudes available to the controller when vectoring arriving aircraft.

Controllers shall not use altitudes below those notified on SMAC except when levels are allocated in accordance with specific procedures that are approved for use within the final approach area.

Question 19

In exceptional cases, for example when the terrain profile is likely to generate GPWS nuisance warnings…

Answer 19

…minimum altitudes higher than the terrain clearance minimum may be specified for use in certain circumstances in order to minimise the likelihood of nuisance warnings. In such cases further details shall be included in MATS Part 2.

Question 20

Unless otherwise prescribed in MATS Part 2, aircraft shall be vectored so as to be established on the final approach track at a distance of not less than…

Answer 20

…5 miles from touchdown.

Question 21

If it is necessary to vector an aircraft through the final approach track before subsequently joining the approach from the opposite side, the controller shall…

Answer 21

…advise the pilot prior to the aircraft passing through the final approach track.

Question 22

Except when Continuous Descent Approach (CDA) procedures are in operation or in an emergency, aircraft shall be positioned so as to maintain…

Answer 22

…a period of stabilised level flight before commencing descent on the glide path, on descent profile of a pilot interpreted approach, or on the nominal descent path of a SRA.

Question 23

At units where CDA procedures are used, details of the operational procedures and the periods of use shall be included in MATS Part 2.

When CDA procedures are in use, aircraft shall be kept at…

Answer 23

…as high an altitude as is appropriate to the procedures whenever possible and controllers shall issue descent instructions at a position compatible with the CDA profile.

This is to enable pilots to intercept the glide path or final approach descent path without a level flight segment after descent when the CDA has commenced.

Distance from touchdown information shall be provided when issuing descent clearance and at any other times specified by the procedure or described in MATS Part 2.

Question 24

Whenever practicable, aircraft shall be vectored to intercept the final approach track at a distance and level such that the aircraft will…

Answer 24

…cross the notified Final Approach Fix/ Point.

Question 25

Aircraft shall be vectored either onto the ILS or MLS localiser or onto an appropriate closing heading offset from the final approach track to enable the pilot to…

Answer 25

…complete the turn onto the final approach track.

Question 26

Closing headings are typically…

Answer 26

…40 degrees offset from the final approach track although individual units may use other offset closing headings as detailed in the MATS Part 2.

Question 27

The controller shall continue to give heading instructions until the aircraft is…

Answer 27

…established on the localiser.

Controllers may instruct the pilot to report established on the localiser where it is judged that it will aid situational awareness.

Question 28

Controllers shall not instruct pilots to establish on the localiser at ranges…

Answer 28

…outside the localiser Designated Operational Coverage (DOC).

If necessary, controllers shall provide additional heading instructions until the aircraft is within the DOC

Question 29

The controller shall use one of the following techniques when issuing a clearance to the pilot to descend on the ILS/MLS glidepath:

Answer 29

(1) Clear the pilot for the ILS/MLS approach only if a descent instruction has been issued to the level published in the ILS/MLS instrument approach procedure at the final approach fix, or to a lower level permitted by the aerodrome’s SMAC; or
(2) Issue a conditional clearance to the pilot to descend on the ILS/MLS glidepath once established on the localiser; or
(3) When it is necessary to ensure that an aircraft joining the ILS/MLS does not commence descent until specifically cleared, solely instruct the pilot to report established on the localiser and to maintain the previously assigned level.

Subsequently, the pilot shall either be cleared to descend on the glidepath or given appropriate alternative level instructions.

The use of “maintain” in sub-paragraph (3) above, is to ensure separation, where required, from traffic below the level of an aircraft joining the ILS or MLS localiser.

When a controller intends to give a pilot successive instructions to establish on a localiser and descend on a glidepath (ILS/MLS), then the use of “maintain” is not required.

Mode C (when available) shall be monitored until the aircraft is established on the localiser in order to enable the controller to take appropriate action should the aircraft descend below the appropriate minimum altitude before following the glidepath.

Controllers shall not instruct pilots to descend on the ILS/MLS when the glidepath intersect would be outside the glidepath DOC.

Question 30

An APV procedure is an instrument procedure which utilises…

Answer 30

…lateral and vertical guidance but does not meet the requirements established for precision approach and landing operations

Question 31

Aircraft shall be vectored either onto the final approach track, or onto a closing heading not more than…

Answer 31

…40° offset from the final approach track to enable the aircraft systems to complete the turn onto final approach

Question 32

APV procedures include an Intermediate Fix.

The aircraft should be vectored towards the Intermediate Fix before…

Answer 32

…turning towards the final approach track in order to be on this track before the Final Approach Point. This will allow the aircraft to cross the Final Approach Point at the level specified in the notified procedure.

Question 33

Non-precision approaches do not incorporate ground-based electronic descent guidance and include…

Answer 33

…localiser only, localiser/DME, VOR, VOR/DME, NDB, NDB/DME, RNAV (LNAV) and SRAs.

Question 34

Non-precision approaches rely on the pilot being in a position to…

Answer 34

…cross the published Final Approach Fix at the specified altitude/height in order to safely complete the approach.

Question 35

Controllers shall vector aircraft onto the final approach track, or onto a heading to close the final approach track at an angle not greater than…

Answer 35

…40° offset from the final approach track.

Whenever practicable, the aircraft is to be established on the final approach track before the Final Approach Fix to enable it to cross the Final Approach Fix at the altitude/ height specified in the notified procedure.

Question 36

For procedures that are not supported by DME, i.e. localiser only, VOR or NDB approaches, the controller shall…

Answer 36

…pass a range check before clearing the aircraft for the approach.

Additional distance from touchdown information may be passed as necessary or requested to assist the pilot to follow the published descent profile for the approach.

Question 37

For procedures that are supported by DME, the controller shall…

Answer 37

…pass a range check and clear the aircraft for the approach when the aircraft is established on the final approach track

Question 38

RNAV (GNSS) approaches are pilot-interpreted non-precision approaches and shall be handled in the same way as other non-precision approaches:

Answer 38

(1) Standard ATC procedures for sequencing and separating aircraft will apply at all times during RNAV approaches. Standard IFR separation will be provided for all IFR traffic.
(2) Pilots will request clearance to fly the procedure. Clearance to fly the procedure permits the pilot to fly in accordance with the published procedure, following the descent profile.
(3) The approach commences at the IAF. Pilots may request vectors, where these are available, for the IAF or may elect to self-position.
(4) Aircraft should normally be cleared to an IAF. Controllers should not issue, and pilots should not accept, vectors to any point inside the Final Approach Fix at any time. When necessary for operational or traffic reasons, aircraft may be vectored to a point on the final approach track no later than the Final Approach Fix. Aircraft to be vectored to the final approach track in this way must be informed of this requirement as soon as possible.
(5) Once an approach has commenced, the aircraft should be allowed to self-position for the approach. Vectors should not then be given unless safety is at risk.
(6) Phraseology associated with RNAV (GNSS) approaches is detailed in CAP 413.

Question 39

The conditions under which an aircraft may be cleared for a visual approach are detailed in Chapter 1.

When an aircraft is cleared for a visual approach the clearance must include, where appropriate…

Answer 39

…a descent restriction that will ensure that the aircraft remains within controlled airspace

Question 40

Where sequencing of IFR flights is in operation, controllers shall provide sufficient information to pilots of VFR or Special VFR flights to enable them to…

Answer 40

…integrate safely into the landing sequence.

Question 41

If it is necessary for a VFR flight to be given a vector, or specific routeing instructions, the pilot shall be instructed to advise the controller if…

Answer 41

…the routeing or vector will prevent the pilot from remaining in VMC.

If it is necessary for a Special VFR flight to be given vectors to establish it in the landing sequence, controllers shall ensure that vectors given do not preclude the responsibility for the pilot to remain clear of cloud, with the surface in sight and keep clear of obstacles by visual reference to the surface

Question 42

The approach radar controller, or such other person as may be detailed, shall notify Approach/Aerodrome Control when an aircraft making a radar approach is approximately…

Answer 42

…8 miles from touchdown.

If landing clearance is not received a subsequent check shall be made at 4 miles.

Clearance to land or alternative instructions received from Approach/Aerodrome Control shall be passed to the aircraft before it reaches a range of 2 miles from touchdown.

Question 43

Where a landing clearance indicator system is installed between the approach radar controller and aerodrome control, it shall be used for…

Answer 43

…giving clearance to land or missed approach instructions.

Question 44

The indicated surface wind, passed with the landing clearance by Approach/Aerodrome Control, may be…

Answer 44

…transmitted to the aircraft at the discretion of the approach radar controller.

Question 45

SRAs may be carried out only where the ATS surveillance system and the procedure have been…

Answer 45

…approved by the CAA for use at a particular aerodrome

Question 46

The situation display must clearly indicate the final approach track and ranges from touchdown for an SRA. If either of these fail to be indicated…

Answer 46

…the approach shall be discontinued and the aircraft instructed to carry out a missed approach if unable to continue visually.

Question 47

Aircraft making a SRA shall be reminded, when on final approach, to…

Answer 47

…check their gear

Question 48

The following conditions apply to an SRA which terminates at 2 miles from touchdown:

Answer 48

(1) Advisory heights through which the aircraft should be passing to maintain the nominal glidepath, together with ranges from touchdown, shall be passed at each mile;
(2) The pilot shall be instructed to check his minimum descent height one mile before advisory heights are discontinued;
(3) Advisory heights shall be discontinued at the one above the highest OCH.

Question 49

The following conditions apply to an SRA which terminates at less than 2 miles from touchdown:

Answer 49

(1) Advisory heights through which the aircraft should be passing to maintain the nominal glidepath, together with ranges from touchdown, shall be passed at each half mile;
(2) Transmissions shall not be interrupted for intervals of more than 5 seconds from a range of 4 miles until the approach is terminated;
(3) The pilot shall be instructed to check his minimum descent height at a range of 2 miles;
(4) Advisory heights shall be discontinued at the one above the highest OCH or at 1 mile, whichever is the sooner;
(5) The controller shall not be responsible for any duties other than those strictly connected with the SRA.

Question 50

Details of glidepath angles to be used and of the associated advisory heights and ranges appropriate to the type of equipment shall be detailed…

Answer 50

…in MATS Part 2

Question 51

Advisory levels, that are published in the UK AIP, for SRAs are initially calculated based either on…

Answer 51

…QNH datum or QFE datum and rounded up to the nearest 10ft.

An adjustment is then made to compute the advisory levels for approaches made using the other datum.

Consequently, for any particular approach, the advisory levels published for the approach will not necessarily be round values.

In order to minimise the potential for misinterpretation or transposition of digits, unless otherwise requested by the pilot, the advisory levels to be passed by ATC when conducting an SRA should be rounded up to the nearest 10 feet.

Question 52

Advisory levels shall be prefixed with an indication of the datum being used, i.e. “height” or “altitude”.

Pilots conducting an approach based on QNH shall be passed…

Answer 52

…the aerodrome/threshold elevation prior to commencing the final descent.

The rounded values to be used when conducting an SRA shall be detailed in MATS Part 2.

Question 53

An aircraft shall be instructed to carry out a missed approach in any of the following circumstances:

Answer 53

(1) On instructions from Approach/Aerodrome Control;
(2) When no landing clearance is received before 2 miles from touchdown (or such other range agreed with Aerodrome Control);
(3) When it appears to be dangerously positioned on final approach.

Question 54

An aircraft is to be advised to carry out a missed approach in any of the following circumstances:

Answer 54

(1) If it reaches a position from which it appears that a successful approach cannot be completed;
(2) If it is not visible on the situation display for any significant interval during the last two miles of the approach;
(3) If the position or identification of the aircraft is in doubt during any portion of the final approach.

Question 55

Missed approach instructions shall include…

Answer 55

…the level to which the aircraft is to climb and, if necessary, heading instructions to keep the aircraft within the missed approach area.

The aircraft shall be instructed to contact Approach Control or, by arrangement, to remain with the approach radar controller.

Question 56

In the event of a pilot initiating a missed approach due to a windshear alert generated from onboard aircraft systems, controllers should be prepared for the aircraft to…

Answer 56

…exceed the missed approach altitude, and should provide traffic information, instructions, and advice as deemed appropriate to ensure safety.

During such manoeuvres, maximum thrust is employed and rates of climb will significantly exceed those for missed approaches executed for other reasons.

These high rates of climb, especially when associated with a missed approach which has a relatively low level-off altitude, can result in pilots exceeding their cleared level.

Aircraft generated windshear alerts also take precedence over the annunciation of TCAS alerts.

Question 57

When a radar approach cannot be continued due to any circumstances, e.g. the amount of clutter, a failure or malfunction of the ATS surveillance system or of the associated air-ground communications…

Answer 57

…the aircraft must be informed immediately.

If the aircraft has not commenced final approach it is to be cleared to an appropriate facility for an alternative approach, in which case procedural separation shall be provided.

If the aircraft has commenced final approach, the approach may be continued either visually or by using an alternative aid, otherwise it is to be cleared for an alternative approach as above.

Question 58

The procedures for the control of departing aircraft by approach radar controllers vary from unit to unit and shall be detailed…

Answer 58

…in MATS Part 2.

Question 59

Departing traffic, which conflict with inbound aircraft receiving an ATS surveillance service, shall be transferred to…

Answer 59

…the approach radar controller, who shall be responsible for providing separation, unless authorised procedures automatically ensuring separation are in operation.