Mats Oral Board Rac 6

Front 1

What SSR code should an Aerodrome controller issue to an aircraft in the circuit?

Back 1

The AIPNZ requires aircraft operating in an aerodrome traffic circuit at controlled aerodromes to squawk 2200 unless they have been issued a discrete or aircraft specific code. Where it becomes evident that an aircraft in the circuit is not squawking 2200 when it should be, the aerodrome controller shall instruct the aircraft to “SQUAWK 2200”.

Front 2

Explain the assignment of SSR codes for formation flying in detail?

Back 2

An individual SSR code may be assigned to each aircraft in a military formation. The last number of the code should correspond to the aircraft's formation number, e.g. RED 2 - 6302.

Alternatively, and for civil formations, an SSR code shall be assigned to the leader and all other aircraft in the formation shall be assigned code 2020.

For formation flights under the control of Ohakea, all aircraft except the leader shall be instructed to squawk STANDBY unless otherwise instructed.

For formation flights under the control of Auckland and Christchurch, all aircraft in the formation shall be instructed to squawk their assigned codes/NORMAL. During close formation, if the datablocks cause interference, all aircraft except the leader may be instructed to squawk STANDBY. The leader shall be instructed to report any relaxation of the formation's configuration.

Note: It is important that controllers are constantly aware of the disposition of formation aircraft in respect of separation from other traffic, particularly when RPS have no datablock, or disappear, while squawking STANDBY. STCA alerting will not occur for aircraft squawking STANDBY. (see RAC 1/CAR1.1 for approved formation flight spacing)

Front 3

What may Mode C information be used to ascertain?

Back 3

Mode C-derived level information may be used to ascertain:

• that aircraft are maintaining assigned levels; or
• that aircraft have vacated, reached or passed levels; or
• the vertical displacement between transponding aircraft.

Front 4

How is Mode C readout verified?

Back 4

• Mode C-derived level information shall be verified prior to being used for separation purposes. The tolerance value shall be ± 200 feet.
• The first radar sector shall verify the accuracy of Mode C-derived level information after departure, on entry into radar coverage or on initial RTF contact by comparison with a pilot reported level.
• There is no requirement to notify a pilot of verification if the Mode C-derived level information is within tolerance.
• If doubt exists as to the accuracy of the data and the aircraft is climbing or descending, the pilot shall be instructed to give a precise report as the aircraft passes through a level to assist verification.
• Mode C-derived level information shall not be verified while an aircraft is in the transition layer.
• Although level information may have been verified by another controller earlier in the flight, it is good operating practice to check the level showing in the datablock whenever an aircraft reports a level.

Front 5

When is an aircraft considered to maintaining its assigned level?

Back 5

An aircraft is considered to be maintaining its assigned level as long as the SSR Mode C-derived level information indicates that it is 200 feet or less from the assigned level.

Front 6

When an aircraft is within the transition layer what precaution must be exercised when using altitude information?

Back 6

This means that when an aircraft is climbing or descending within the transition layer the altitude shown in a datablock is not necessarily that shown on the aircraft altimeter and reported by the pilot.

Front 7

Back 7

Front 8

Describe the methods of primary radar identification that an aerodrome or procedural approach controller may use?

Back 8

Correlation of a particular radar position symbol with an aircraft reporting its position: Radar identification may be achieved by correlating an RPS with an aircraft reporting its position over, or as a bearing and distance from, a prescribed point displayed on the radar map. An aircraft may be accepted as identified provided that the RPS is within 5 NM of the reported position and the track of the target is consistent with the route or the reported heading of the aircraft.

Front 9

Back 9

Front 10

Describe the methods of SSR identification that an aerodrome or procedural approach controller may use?

Back 10

Front 11

What are the 3 SSR emergency codes and what do they indicate?

Back 11

The pilot of an aircraft encountering a state of emergency may select the following codes to indicate the situation:

• 7700 - Aircraft emergency
• 7600 - Radio failure
• 7500 - Unlawful interference

Front 12

What shall a controller do when it has been established that an aircraft is transponding on SSR code 7500?

Back 12

Whenever it has been established that the aircraft is transponding on SSR code 7500 the controller shall attempt to verify by RTF with the aircraft concerned that the code selection is intentional. The phraseology to be used is:

"CONFIRM SQUAWKING SEVEN FIVE ZERO ZERO" Whenever it has been verified that the code has been intentionally selected, or when no verification can be obtained, it shall be assumed that the aircraft has suffered unlawful interference.

Note: The definition of "Unlawful interference" includes hijack and other meanings as detailed in RAC 1.

When an ATS unit considers that a strayed or unidentified aircraft may be the subject of unlawful interference, the CAA Emergency Operations Centre (EOC)  0-4-566 5271 shall be immediately informed

Front 13

The provision of any radar service must not restrict other Tower functions. What are these?

Back 13

ATS surveillance shall only be used in support of an aerodrome or procedural approach control service to the extent that it does not distract or prevent:

• an aerodrome controller from fulfilling the imperative to maintain a visual observation of operations on and in the vicinity of the aerodrome;
• an aerodrome or procedural approach controller from fulfilling the primary responsibilities of their duties.

Front 14

How may a Tower controller use information on the Tower situation display?

Back 14

In no circumstance shall an aerodrome or procedural approach controller use the situation display to vector aircraft.

An aerodrome or procedural approach controller may read information off a situation display to:

• establish or confirm an aircraft's position, including distance from a DME station;
• establish or confirm an aircraft's spatial relationship to other aircraft;
• establish or confirm geographical separation;
• establish or confirm vertical separation following level verification, applying RAC 6 Application of Altitude Display procedures;
• comply with or give effect to release instructions. These may be imposed by a radar controller for specific flights or detailed in LUO/LOA;
• establish or confirm that an IFR flight is separated from a VFR flight operating in a control zone/Terminal CTA sector. This separation may be used provided that:

▪︎the IFR flight is navigating by visual reference and is observed to be at least two nautical miles clear of the applicable control zone/Terminal CTA sector; and

▪︎the control zone/Terminal CTA sector is marked on the situation display; and

▪︎instructions are issued to control the track of the IFR flight to ensure that separation, once established, will be maintained;

• provide information to assist in the control of aircraft operating by visual reference within the vicinity of the aerodrome, e.g. "EXTEND DOWNWIND", "TURN BASE LEG NOW";

Note: The use of the situation display in making decisions in relation to the control of circuit traffic should be kept to a minimum.

• provide navigational assistance in the form of:

▪︎an observed position;

▪︎track and distance to a significant point;

▪︎position relative to a specified track or airspace, including the provision of a suggested direction of flight to a VFR flight, e.g.:

• when an aircraft is in obvious need of navigational assistance in order to comply with an ATC clearance, e.g. "SUGGEST YOU PROCEED (direction) BOUND"; or
• when it appears that separation or airspace may be infringed, e.g. "SUGGEST YOU PROCEED (direction) BOUND TO KEEP YOU CLEAR OF ....".

In both cases, further routing instructions shall be passed to the aircraft that clearly indicate that the pilot is responsible for the navigation, e.g. "CONTINUE TRACKING (details) VFR".

• Traffic information

▪︎assist in the provision of traffic information;

▪︎provide traffic avoidance advice.