APS Flashcards
What methods of identification can be used when using PSR
The turn method
The departing aircraft method
Position report method
How do you identify Aircraft using the Turn method?
An aircraft may be identified by ascertaining its heading and, following a period of track observation, correlating the observed movement of a particular Position Indication with:
(1) the acknowledged execution of an instruction to alter heading by at least 30°;
(2) one or more changes of heading of at least 30°‚ as instructed by another controller;
(3) one or more changes of heading of at least 30° reported by the pilot.
A turn for identification does not constitute the provision of a surveillance service. However, controllers should take into consideration, terrain, other surveillance returns, PSR coverage and the RoA Regulations before instructing an aircraft to alter heading.
In using the turn method the controller shall:
(1) verify that the movements of not more than one Position Indication correspond with those of the aircraft;
(2) exercise caution particularly when employing this method in areas where changes of aircraft heading are commonly made as a navigational routine.
How do you identify Aircraft using the Departing Aircraft method?
By observing and correlating the Position Indication of a departing aircraft to a known airborne time. Identification is to be achieved within one mile of the end of the runway unless otherwise authorised by the CAA.
Particular care should be taken to avoid confusion with aircraft overflying the aerodrome, making a missed approach, departing from an adjacent runway or holding overhead the aerodrome.
How do you identify Aircraft using the Position Report method?
By correlating a particular Position Indication with a report from the pilot that the aircraft is:
(1) over an exact reporting point which is displayed on the situation display; or
(2) at a particular distance not exceeding 30 NM on a particular radial from a colocated VOR/DME or TACAN (DME). The source facility must be displayed on the situation display; or
(3) over a notified visual reference point or prominent geographical feature, in either case approved for the purpose and displayed on the situation display, provided that the flight is operating with visual reference to the surface and at a height of 3000 ft or less above the surface.
The identification must follow a period of track observation sufficient to enable the controller to compare the movement of the Position Indication with the pilot’s reported route. The reported position and level of the aircraft must indicate that it is within known PSR cover.
This method must be reinforced by an alternative method if there is any doubt about the identification because of:
(1) the close proximity of other returns; or
(2) inaccurate reporting from aircraft at high level or some distance from navigational facilities.
A pilot is to be informed as soon as their aircraft has been identified. When operating inside controlled airspace, the pilot of an aircraft need only be so informed if the identification is achieved by the turn method.
How do you identify aircraft using SSR
When using Mode A to identify aircraft, one of the following methods is to be employed:
(1) Observing the pilot’s compliance with the instruction to select a discrete fourdigit code;
(2) Recognising a validated four-digit code previously assigned to an aircraft callsign. When code/callsign conversion procedures are in use and the code/callsign pairing can be confirmed, the callsign displayed in the data block may be used to establish and maintain identity;
(3) Observing an IDENT feature when it has been requested.
Caution must be exercised when employing this method because simultaneous requests for SPI transmissions within the same area may result in misidentification.
Unless MATS Pt 2 states otherwise, aircraft displaying a conspicuity or special purpose code are not to be identified by this method.
When do you inform pilots of their identification and pass position information
SSR: inform identified, no position.
Turn method: inform identified, position required.
Position report: inform identified, no position.
Departing Aircraft: inform identified, no position.
How do you identify aircraft using Mode S?
Direct recognition of the Aircraft Identification Feature on the situation display may be used to establish surveillance identification, subject to either:
(1) correlation of the Aircraft Identification Feature with the aircraft identification entered in the flight plan and displayed to controllers on flight progress strips; or
(2) correlation of the Aircraft Identification Feature with the aircraft’s callsign used in a directed RTF transmission to the controller. However, controllers shall exercise particular caution when there are aircraft with similar callsigns on the frequency and shall utilise an alternative method if they have any doubt about the surveillance identification.
Whenever it is observed on the situation display that the down-linked Aircraft Identification Feature is different from that expected from the aircraft, the pilot shall be requested to confirm and, if necessary, re- enter the Aircraft Identification Feature.
If the discrepancy continues to exist following confirmation by the pilot that the correct aircraft identification has been set in the Aircraft Identification Feature, the controller shall take the following minimum actions:
(1) inform the pilot of the persistent discrepancy;
(2) assign a discrete Mode A code; and
(3) notify the erroneous Aircraft Identification Feature transmitted by the aircraft to the next control position or unit.
Transfer of identification using the Mode S Aircraft Identification Feature relies on both units having appropriate Mode S surveillance capability; therefore, it shall only be conducted in accordance with locally agreed arrangements and specified in MATS Part 2.
Using mode C, when is an aircraft considered to be at an assigned level?
An aircraft may be considered to be at an assigned level provided that the Mode C readout indicates 200 ft or less from that level
Using mode C, when is an aircraft considered to have left a level?
An aircraft which is known to have been instructed to climb or descend may be considered to have left a level when the Mode C readout indicates a change of 400 ft or more from that level and is continuing in the anticipated direction;
What is the definition of a basic service
A Basic Service is an ATS provided for the purpose of giving advice and information useful for the safe and efficient conduct of flights. This may include weather information, changes of serviceability of facilities, conditions at aerodromes, general airspace activity information, and any other information likely to affect safety. The avoidance of other traffic is solely the pilot’s responsibility.
What is the definition of a Traffic service
A Traffic Service is a surveillance based ATS, where in addition to the provisions of a Basic Service, the controller provides specific surveillance derived traffic information to assist the pilot in avoiding other traffic. Controllers may provide headings and/or levels for the purposes of positioning and/or sequencing; however, the controller is not required to achieve deconfliction minima, and the pilot remains responsible for collision avoidance.
Under a TS what is normally considered to be relevant traffic?
Traffic is normally considered to be relevant when, in the judgement of the controller, the conflicting aircraft’s observed flight profile indicates that it will pass within 3 NM and, where level information is available, 3,000 ft of the aircraft in receipt of the Traffic Service or its level-band if manoeuvring within a level block. However, controllers may also use their judgment to decide on occasions when such traffic is not relevant, e.g. passing behind or within the parameters but diverging. Controllers shall aim to pass information on relevant traffic before the conflicting aircraft is within 5 NM, in order to give the pilot sufficient time to meet their collision avoidance responsibilities and to allow for an update in traffic information if considered necessary.
Can you provide a TS below the terrain safe level?
Subject to ATS surveillance system coverage, Traffic Service may be provided below ATC unit terrain safe levels; however, pilots remain responsible for terrain clearance at all times. Other than when following a notified instrument flight procedure, a pilot intending to descend below the ATC unit terrain safe level shall be reminded that they remain responsible for terrain clearance.
What is the definition of a deconfliction service?
A Deconfliction Service is a surveillance based ATS where, in addition to the provisions of a Basic Service, the controller provides specific surveillance derived traffic information and issues headings and/or levels aimed at achieving planned deconfliction minima, or for positioning and/ or sequencing. However, the avoidance of other traffic is ultimately the pilot’s responsibility.
What are deconfliction minimum against uncoordinated traffic when providing a DS?
The deconfliction minima against unco-ordinated traffic are:
5 NM laterally (subject to surveillance capability and regulatory approval); or
3,000 ft vertically and, unless the SSR code indicates that the Mode C data has been verified, the surveillance returns, however presented, should not merge. (Note: Mode C can be assumed to have been verified if it is associated with a deemed validated Mode A code. The Mode C data of aircraft transponding code 0000 is not to be utilised in assessing deconfliction minima).
The deconfliction minima against aircraft that are being provided with an ATS by the same controller, or that have been subject to co-ordination, are:
3 NM laterally (subject to surveillance capability and regulatory approval); or
1,000 ft vertically; (2,000 ft within active MDA/MTA above FL410, and above FL290 where both aircraft are not RVSM approved); or
500 ft vertically (subject to regulatory approval).
Can you provide a DS below the terrain safe level?
A Deconfliction Service shall only be provided to aircraft operating at or above the ATC unit’s terrain safe level, other than when a controller at an Approach Control unit provides an ATS to aircraft on departure from an aerodrome and climbing to the ATC unit’s terrain safe level, or to aircraft following notified instrument approach procedures. In all other circumstances, if a pilot requests descent below ATC unit terrain safe levels, controllers shall no longer provide a Deconfliction Service but should instead, subject to surveillance and RTF coverage, apply a Traffic Service and inform the pilot.
When can pilots be cleared for a visual approach?
To expedite traffic at any time, IFR flights, either within or outside controlled airspace, may be authorised to execute visual approaches if the pilot reports that visual reference to the surface can be maintained and:
(1) the reported cloud ceiling is at or above the level of the beginning of the initial approach segment; or
(2) the pilot reports at any time after commencing the approach procedure that the visibility will permit a visual approach and landing, and a reasonable assurance exists that this can be accomplished.
Controllers shall not clear an aircraft for a visual approach when the RVR is less than 800m. If a pilot requests a visual approach when the RVR is less than 800m, controllers shall inform the pilot that this type of approach is unavailable and request the pilot’s intentions.
What are the following frequencies (1) Oxford Tower (2) Oxford Ground (3) Oxford Approach/Radar (4) Oxford Director (5) D+D VHF and UHF (4) Oxford Fire.
Oxford Tower 133.430
Oxford Ground 121.955
Oxford Approach /Radar 125.090
Oxford Director 119.980
D+D VHF & UHF 121.5 & 243.0
Oxford Fire 121.6
What precision approaches are available at Oxford?
ILS/DME/NDB Runway 19
What non-precision approaches are available at Oxford?
NDB Runway 01
LOC/DME/NDB Runway 19
NDB Runway 19
When shall APS transmit IRVR to aircraft?
RVR reporting to aircraft is started:
(1) whenever the aerodrome meteorological report shows the visibility to be less than 1,500 metres;
(2) whenever the IRVR display is indicating an RVR value equal to or less than the maximum for that system;
(3) whenever shallow fog is reported and during a period for which it is forecast.
IRVR values are to be passed to aircraft at the beginning of each approach for landing and, thereafter, whenever there is a significant change in the RVR until the aircraft have landed. A significant change is defined as a change in value of one increment or more. The current RVR value is also to be passed to aircraft before take-off.
Even though a pilot may have received an IRVR value from the ATIS broadcast, controllers must ensure that they pass the current value as specified above.
When must a pilot fly IFR?
A pilot must fly according to the IFR:
(1) If the airspace has been notified as Class A;
(2) If the meteorological conditions preclude VFR flight or (within a Control Zone) Special VFR flight.
What are the reduced separations in the vicinity of an Aerodrome?
In the vicinity of aerodromes, the standard separation minima may be reduced if:
(1) adequate separation can be provided by the aerodrome controller when each aircraft is continuously visible to this controller; or
(2) each aircraft is continuously visible to the pilots of other aircraft concerned and the pilots report that they can maintain their own separation; or
(3) when one aircraft is following another, the pilot of the succeeding aircraft reports the other aircraft is in sight and can maintain their own separation.
What are the threshold elevations for Runways 01 and 19?
Runway 01: 249ft
Runway 19: 258ft
Aerodrome elevation: 263ft
What is the Oxford Squawk code allocation:
Oxford Approach: 4501 - 4516
Frequency monitoring code: 4517
Oxford Approach Basic Service: 4520
