Section (b) a clearance limit has been imposed t - Manual of Standards Part 172—Air Traffic Services - (b) a clearance limit has been imposed temporarily and it is expected that the requirement to hold will have elapsed before the aircraft arrives at the designated holding point. | Zoe
(b) a clearance limit has been imposed t(b) a clearance limit has been imposed temporarily and it is expected that the requirement to hold will have elapsed before the aircraft arrives at the designated holding point.
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12.1.1.1 An ATC clearance, and its amendments during the flight apply only:
(a) to the first point at which the aircraft leaves controlled airspace; or
(b) to the first landing point if the flight is wholly within controlled airspace; or
(c) to the clearance limit if issued; or
(d) until the expiration of a clearance void time; or
(e) until cancelled by a controller.
12.1.2 Level Assignment
12.1.2.1 Clearances issued must enable the pilot to comply with CAR 157.
12.1.2.2 Block Level Clearances must not be issued to:
(a) civil aircraft in Class E airspace; or
(b) aircraft to which the Mach Number Technique has been applied.
12.1.2.3 Unless ATC instructs otherwise, a pilot intending to land at an aerodrome within Class D airspace may descend to join the aerodrome traffic circuit after he or she has established 2-way communications with the Tower.
12.1.3 Clearances for Special VFR Aircraft
12.1.3.1 At pilot request, a SPECIAL VFR clearance may be issued for a VFR flight when:
(a) within a control zone;
(b) in a control area next to a control zone for the purpose of entering or leaving the zone;
(c) by day;
(d) when VMC do not exist; and
(e) an IFR flight will not be unduly delayed.
12.1.3.2 In the application of Special VFR, the following are Australian requirements, which differ from those stated in ICAO PANS-ATM:
(a) Special VFR is not available in Class E airspace.
(b) Visibility assessment is the responsibility of the pilot.
12.1.4 Clearances Below LSALT
12.1.4.1 A pilot may be assigned a level below the LSALT provided that:
(a) the pilot has reported “VISUAL”; and
(b) “VISUAL” is appended to the level assigned; and
(c) by night, the clearance is prefixed with “WHEN ESTABLISHED IN THE CIRCLING AREA”.
12.1.4.2 ATC may authorise operations below the LSALT to the pilot of a military or Coastwatch flight when requested by the pilot of the operation for operational reasons. This procedure does not substitute for the conditions of a visual approach at night.
12.1.5 Clearance Limits
12.1.5.1 When a clearance limit is cancelled, an onwards clearance specifying the level and route to be flown from that point must be issued.
12.1.5.2 A description of a holding path to be flown at the clearance limit is not required when:
(a) the holding point is published in aeronautical documents;
(b) a clearance limit has been imposed temporarily and it is expected that the requirement to hold will have elapsed before the aircraft arrives at the designated holding point.
12.1.6 Clearance Readbacks
12.1.6.1 ATS personnel must ensure that those elements identified in AIP are to be read back correctly by the pilot.
12.1.7 Transfer of identification
12.1.7.1 Transfer of identification may be carried out by 1 of the following methods:
(a) designation of the position indication by automated means, if only 1 position indication is indicated and there is no possible doubt of correct identification;
(b) notification of the aircraft’s discrete SSR code or aircraft address;
(c) notification that the aircraft is SSR Mode S-equipped with an aircraft identification feature when SSR Mode S coverage is available;
(d) notification that the aircraft is ADS-B equipped with an aircraft identification feature when compatible ADS-B coverage is available;
(e) direct designation (pointing with the finger) of the position indication, if the 2 situation displays are adjacent, or if a common conference type of situation display is used;
Note: Attention must be given to any errors which might occur due to parallax effects.
(f) designation of the position indication by reference to, or in terms of, bearing and distance from a geographical position or navigational facility accurately indicated on both situation displays, together with the track of the observed position indication if the route of the aircraft is not known to both controllers;
Note: Caution must be exercised before transferring identification using this method, particularly if other position indications are observed on similar headings and in close proximity to the aircraft under control. Inherent radar deficiencies, such as inaccuracies in bearing and distance of the radar position indications displayed on individual situation displays and parallax errors, may cause the indicated position of an aircraft in relation to the known point to differ between the 2 situation displays.
(g) the transferring controller instructing the aircraft to change SSR code, and the accepting controller observing the change;
(h) the transferring controller instructing the aircraft to squawk/transmit IDENT, and the accepting controller observing this response.
Note: Use of procedures (g) and (h) requires prior coordination between the controllers, since the indications to be observed by the accepting controller are of short duration.
12.1.8 Clearance by Establishment of 2-way Communications
12.1.8.1 For this subsection, 2-way communication is established if ATC responds to a pilot’s radio call with the aircraft’s radio identification.
12.1.8.2 In addition to issuing a pilot with a specific clearance or instruction, ATC may authorise an aircraft to enter Class D airspace by establishing 2-way communication with it.
Notes:1 If ATC responds to a radio call with the aircraft identification (generally including an instruction or report requirement), 2-way radio communications have been established and the pilot can enter the Class D airspace.2 If ATC responds to the initial radio call without using the aircraft identification, 2-way radio communication has not been established and the pilot may not enter the Class D airspace.3 If workload or traffic conditions prevent immediate entry into the Class D airspace, ATC should expressly instruct the pilot to remain outside the Class D airspace.4 The pilot of an aircraft is required to comply with any instruction that ATC includes with the establishment of 2-way communication, including an instruction to remain outside the Class D airspace.
Section 12.2: En-route/Terminal Clearances
12.2.1 Departure Clearances
12.2.1.1 Where SIDs are published, they must be issued to IFR aircraft departing at night, or by day in IMC.
12.2.1.2 Tracking instructions must be specified when:
(a) SIDS are not published; or
(b) a SID is cancelled; or
(c) a visual departure clearance is issued in VMC by day in lieu of a SID; or
(d) aircraft or ground based navigation aid(s) are not available.
12.2.1.3 ATC must notify the pilot of the expectation for a visual departure.
12.2.2 ATC Route Clearances
12.2.2.1 An ATC route clearance must include at least the first position at which the flight-planned route is joined.
12.2.2.2 Route clearances issued to aircraft operating VFR at night must be in accordance with the flight-planned route except:
(a) when the pilot specifically requests another route; or
(b) when an amended route is deemed satisfactory in relation to the planned route (e.g. coastline flying); or
(c) for short-term route variations:
(i) by vectoring; or
(ii) within 30 NM of a controlled aerodrome, by visual tracking.
12.2.2.3 Route clearances authorising RNAV tracking must only be permitted for flight segments contained within ATS surveillance system coverage unless:
(a) the route is published in AlP; or
(b) prior coordination has been conducted between affected units.
12.2.3 STAR Clearances
12.2.3.1 A STAR clearance must contain:
(a) STAR identifier;
(b) a TRANSITION route when applicable;
(c) a RUNWAY when applicable; and
(d) an instrument or visual termination procedure when applicable; and
(e) a LEVEL assignment.
12.2.3.2 Descent must be assigned in sufficient time to allow pilots to comply with vertical navigation requirements.
12.2.3.3 When an aircraft is vectored away from a Transition Route associated with a STAR, and the intention is that the aircraft will rejoin the Transition to complete the STAR procedure, ATC must re-state any restrictions/requirements applicable to the Transition Route. When an aircraft is vectored, the aircraft must be re-positioned to enable the Arrival Route to be flown and re-cleared.
12.2.4 Approach Clearances
12.2.4.1 A controller must not issue an air traffic clearance which authorises or requires a pilot to descend in IMC below the lowest safe altitude for the route segment in a manner different from that specified in:
(a) DME, DME or GPS, or GPS Arrival procedures;
(b) the procedures, plan and profile diagram of IAL charts published in AIP/FLIP Terminal;
(c) an approved instrument approach procedure published in NOTAM;
(d) approved ATS surveillance system procedures.
12.2.4.2 When a flight other than that described in paragraph 12.2.4.3 is within 30 NM of an aerodrome, a visual approach may be authorised by day or night to:
(a) a VFR flight; or
(b) an IFR flight when:
(i) the pilot has established and can continue flight to the aerodrome with continuous visual reference to the ground or water; and
(ii) the visibility along the flight path is not less than 5,000 M (or by day, the aerodrome is in sight).
12.2.4.3 In addition to the requirements of paragraph 12.2.4.2, with the exception of Australian and New Zealand operators and aircraft conducting independent visual approaches at Sydney, HEAVY jet aircraft may only be assigned a visual approach when:
(a) specifically requested by the pilot and the pilot has reported the landing runway is in sight; or
(b) the straight-in approach aid is unserviceable.
12.2.4.4 In the case of the straight-in approach aid being unserviceable, the aircraft must be:
(a) vectored to intercept final no closer than 8 NM from the runway threshold, at an altitude not less than 2,500 FT above aerodrome level (AAL); and
(b) assigned a straight-in visual approach when:
(i) established on final or on a heading to intercept final course at an angle of not more than 30 degrees;
(ii) visual glideslope guidance (VASIS/PAPI) is available; and
(iii) the pilot has reported the runway in sight.
12.2.4.5 When being vectored at night, an IFR aircraft, other than a HEAVY jet aircraft as described at paragraph 12.2.4.3, may be assigned a visual approach at any distance from an aerodrome, if:
(a) the aircraft has been assigned the minimum vector altitude; and
(b) the aircraft has been given heading instructions to intercept final or to position the aircraft within the circling area of the aerodrome; and
(c) the following phraseology is used to assign the visual approach:
(i) “WHEN ESTABLISHED ON THE VASIS/GLIDEPATH CLEARED VISUAL APPROACH”; or
(ii) “WHEN ESTABLISHED IN THE CIRCLING AREA CLEARED VISUAL APPROACH”.
Section 12.3: Aerodrome Clearances
12.3.1 General
12.3.1.1 In addition to the provisions of ICAO PANS-ATM, Chapter 7.1, aerodrome controllers must issue information and clearances with the object of preventing collisions between aircraft and vehicles operating on the helicopter movement area, but excluding helicopter landing sites situated on apron areas or beyond the sight of the tower controller.
12.3.1.2 Whenever more than one runway is in use, the runway number must be included in the line up, take-off or landing clearance.
12.3.1.3 When issuing clearances or instructions, controllers must take into account the hazards that may be caused by thrust stream turbulence. When such hazards may not be obvious to other aircraft, vehicles and personnel, an appropriate caution must be issued.
12.3.2 Taxi and Pre-Taxi Instructions
12.3.2.1 A taxi instruction which contains a taxi limit beyond a runway must include a “CROSS RUNWAY (number)” instruction.
12.3.2.2 Aircraft required to hold short of a runway intersecting the taxi route, must be issued a taxi instruction limit of the holding point associated with the intersecting runway. Taxi instructions must not include a position beyond that of a required intermediate holding point.
12.3.2.3 Departing and arriving aircraft must be issued with an instructions to “CROSS RUNWAY (number)” if previously issued with:
(a) a taxi instruction limit of the holding point of a runway intersecting the taxi route; or
(b) an instruction to “HOLD SHORT” of a runway.
12.3.3 Line Up and Take-off Clearances
12.3.3.1 When aircraft are authorised to line up on the same or intersecting runways simultaneously, traffic information must be provided as appropriate.
12.3.3.2 An aircraft delayed by the traffic situation must be issued traffic information if appropriate, and instructed to hold position off the runway, or must be issued a conditional line-up clearance.
12.3.3.3 When an instruction to line up does not include a take-off clearance and is issued with the departure instructions, the appropriate holding instruction must be given.
12.3.3.4 The words “TAKE-OFF” must be used only for clearing an aircraft for take-off.
12.3.3.5 The words “TAKE-OFF” must be used as the last words of a take-off clearance, except when the following information must be appended:
(a) an instruction specifying a turn or circuit direction; or
(b) at a military airfield the state of the arrestor system;
12.3.3.6 In all other cases, the words “TAKE-OFF” must be used as the last words of the take- off clearance.
12.3.3.7 Unless requested, a take-off clearance must not be issued to a helicopter when the tailwind component exceeds 5 KT.
12.3.3.8 Within controlled airspace and at a controlled aerodrome, helicopters may be granted an airways and/or take-off clearance from any area which is nominated by ATC or the pilot, and assessed by the pilot as being suitable as a HLS.
12.3.3.9 Within a Class D CTR, a clearance to take-off is a clearance to operate within the CTR.
12.3.4 Landing Clearances
12.3.4.1 Clearance to land must not be issued before:
(a) the aircraft has commenced final approach of a PAR or straight in instrument approach; or
(b) the aircraft has been sighted by the tower controller:
(i) on the late downwind leg of the circuit pattern;
(ii) on base leg; or
(iii) on final in the case of a straight in visual approach.
12.3.4.2 Observation by radar satisfies the sighting requirement.
12.3.4.3 Unless requested by the pilot, a landing clearance must not be issued to a helicopter when the tailwind exceeds 5 KT.
12.3.4.4 When a tower controller has been advised that a general aviation aircraft with retractable undercarriage has experienced abnormal operations, a check gear down call must be made with the landing clearance.
12.3.4.5 A military aircraft must be instructed to check gear down when being cleared for an overshoot, cleared to land or cleared for a touch-and-go landing. Controllers must issue the instruction as soon as possible after a pilot indicates that his undercarriage is down and locked. Where a pilot neglects to declare his undercarriage status, the controller must instruct the pilot to check gear down.
12.3.4.6 If an arriving aircraft reports at a position where it should normally have been seen but has not been sighted, the aircraft must be advised of not being in sight by the controller when cleared to land.
12.3.4.7 Landing clearances must apply to aircraft which are restricted to the same or crossing landing paths. However, when such aircraft are permitted to land in parallel paths, clearances may be given for simultaneous landings. In these circumstances, notwithstanding that the pilot of each aircraft must be responsible for the maintenance of separation, the tower controller must issue alternative instructions should the possibility of a confliction arise.
12.3.4.8 The tower controller must allocate one landing sequence number to a landing formation, thus treating the formation as one aircraft.
12.3.4.9 When the landing area is occupied by another aircraft or is obstructed, arriving aircraft may be issued with a clearance to:
(a) continue approach if there is no immediate assurance that the landing areas will become available. This must be followed by the appropriate clearance; or
(b) go around, or orbit if in a position to do so, should the landing area not be available. When required, a clearance to commence a second approach or hold must follow these instructions. The nature of the obstruction must be advised if not apparent to the approaching aircraft.