NCO.OP.116 Performance-based navigation – aeroplanes and helicopters

PBN OPERATIONS For operations where a navigation specification for performance-based navigation (PBN) has been prescribed and no specific approval is required in accordance with SPA.PBN.100, the pilot-in-command should:

(a)use operating procedures specifying:

(1)normal, abnormal and contingency procedures;

(2)electronic navigation database management; and

(3)relevant entries in the minimum equipment list (MEL), where applicable;

(b)ensure that he/she is appropriately trained for the intended operation.

MONITORING AND VERIFICATION

(a)Preflight and general considerations

(1)At navigation system initialisation, the pilot-in-command should confirm that the navigation database is current and verify that the aircraft position, if required, has been entered correctly.

(2)The active flight plan, if applicable, should be checked by comparing the charts or other applicable documents with navigation equipment and displays. This includes confirmation of the waypoint sequence, reasonableness of track angles and distances, any altitude or speed constraints, and, where possible, which waypoints are fly-by and which are fly-over. Where relevant, the RF leg arc radii should be confirmed.

(3)The pilot-in-command should check that the navigation aids critical to the operation of the intended PBN procedure are available.

(4)The pilot-in-command should confirm the navigation aids that should be excluded from the operation, if any.

(5)An arrival, approach or departure procedure should not be used if the validity of the procedure in the navigation database has expired.

(b)Departure

(1)Prior to commencing a take-off on a PBN procedure, the pilot-in-command should verify that the area navigation system is available and operating correctly and the correct aerodrome and runway data has been loaded. A positive check should be made that the indicated aircraft position is consistent with the actual aircraft position at the start of the take-off roll (aeroplanes) or lift-off (helicopters).

(2)Where GNSS is used, the signal should be acquired before the take-off roll (aeroplanes) or lift-off (helicopters) commences.

(3)Unless automatic updating of the actual departure point is provided, the pilot-in-command should ensure initialisation on the runway or FATO either by means of a manual runway threshold or intersection update, as applicable. This is to preclude any inappropriate or inadvertent position shift after take-off.

(c)Arrival and approach

(1)The pilot-in-command should verify that the navigation system is operating correctly and the correct arrival procedure and runway (including any applicable transition) are entered and properly depicted.

(2)Any published altitude and speed constraints should be observed.

(3)The pilot-in-command should check approach procedures (including alternate aerodromes if needed) as extracted by the system (e.g. CDU flight plan page) or presented graphically on the moving map, in order to confirm the correct loading and the reasonableness of the procedure content.

(4)Prior to commencing the approach operation (before the IAF), the pilot-in-command should verify the correctness of the loaded procedure by comparison with the appropriate approach charts. This check should include:

(i)the waypoint sequence;

(ii)reasonableness of the tracks and distances of the approach legs and the accuracy of the inbound course; and

(iii)the vertical path angle, if applicable.

(d)Altimetry settings for RNP APCH operations using Baro VNAV

(1)Barometric settings

(i)The pilot-in-command should set and confirm the correct altimeter setting and check that the two altimeters provide altitude values that do not differ more than 100 ft at the most at or before the FAF.

(ii)The pilot-in-command should fly the procedure with:

(A)a current local altimeter setting source available — a remote or regional altimeter setting source should not be used; and

(B)the QNH/QFE, as appropriate, set on the aircraft’s altimeters.

(2)Temperature compensation

(i)For RNP APCH operations to LNAV/VNAV minima using Baro VNAV:

(A)the pilot-in-command should not commence the approach when the aerodrome temperature is outside the promulgated aerodrome temperature limits for the procedure, unless the area navigation system is equipped with approved temperature compensation for the final approach;

(B)when the temperature is within promulgated limits, the pilot-in-command should not make compensation to the altitude at the FAF; and

(C)since only the final approach segment is protected by the promulgated aerodrome temperature limits, the pilot-in-command should consider the effect of temperature on terrain and obstacle clearance in other phases of flight.

(ii)For RNP APCH operations to LNAV minima using Baro VNAV:

(A)the pilot-in-command should consider the effect of temperature on terrain and obstacle clearance in all phases of flight, in particular on any step-down fix;

(B)if the temperature is outside promulgated limits for RNP APCH to LNAV/VNAV minima, the pilot-in-command should not use a Baro VNAV function for vertical guidance, unless the area navigation system is equipped with approved temperature compensation for the final approach.

(e)Sensor and lateral navigation accuracy selection

(1)For multi-sensor systems, the pilot-in-command should verify, during the approach, that the GNSS sensor is used for position computation.

(2)For aircraft with RNP input selection capability, the pilot-in-command should confirm that the indicated RNP value is appropriate for the PBN operation.

MANAGAMENT OF THE NAVIGATION DATABASE

(a)For RNAV 1, RNAV 2, RNP 1, RNP 2, and RNP APCH, the pilot-in-command should neither insert nor modify waypoints by manual entry into a procedure (departure, arrival or approach) that has been retrieved from the database. User-defined data may be entered and used for waypoint altitude/speed constraints on a procedure where said constraints are not included in the navigation database coding.

(b)For RNP 4 operations, the pilot-in-command should not modify waypoints that have been retrieved from the database. User-defined data (e.g. for flex-track routes) may be entered and used.

(c)The lateral and vertical definition of the flight path between the FAF and the missed approach point (MAPt) retrieved from the database should not be revised by the pilot-in-command.

DISPLAYS AND AUTOMATION

(a)For RNAV 1, RNP 1, and RNP APCH operations, the pilot-in-command should use a lateral deviation indicator, and where available, flight director and/or autopilot in lateral navigation mode.

(b)The appropriate displays should be selected so that the following information can be monitored:

(1)the computed desired path;

(2)aircraft position relative to the lateral path (cross-track deviation) for FTE monitoring; and

(3)aircraft position relative to the vertical path (for a 3D operation).

(c)The pilot-in-command of an aircraft with a lateral deviation indicator (e.g. CDI) should ensure that lateral deviation indicator scaling (full-scale deflection) is suitable for the navigation accuracy associated with the various segments of the procedure.

(d)The pilot-in-command should maintain procedure centrelines unless authorised to deviate by ATC or demanded by emergency conditions.

(e)Cross-track error/deviation (the difference between the area-navigation-system-computed path and the aircraft-computed position) should normally be limited to ± ½ time the RNAV/RNP value associated with the procedure. Brief deviations from this standard (e.g. overshoots or undershoots during and immediately after turns) up to a maximum of 1 time the RNAV/RNP value should be allowable.

(f)For a 3D approach operation, the pilot-in-command should use a vertical deviation indicator and, where required by AFM/POH limitations, a flight director or autopilot in vertical navigation mode.

(g)Deviations below the vertical path should not exceed 75 ft at any time, or half-scale deflection where angular deviation is indicated, and not more than 75 ft above the vertical profile, or half-scale deflection where angular deviation is indicated, at or below 1 000 ft above aerodrome level. The pilot-in-command should execute a missed approach if the vertical deviation exceeds this criterion, unless the pilot-in-command has in sight the visual references required to continue the approach.

VECTORING AND POSITIONING

(a)ATC tactical interventions in the terminal area may include radar headings, ‘direct to’ clearances which bypass the initial legs of an approach procedure, interceptions of an initial or intermediate segments of an approach procedure or the insertion of additional waypoints loaded from the database.

(b)In complying with ATC instructions, the pilot-in-command should be aware of the implications for the navigation system.

(c)‘Direct to’ clearances may be accepted to the IF provided that it is clear to the pilot-in-command that the aircraft will be established on the final approach track at least 2 NM before the FAF.

(d)‘Direct to’ clearance to the FAF should not be acceptable. Modifying the procedure to intercept the final approach track prior to the FAF should be acceptable for radar-vectored arrivals or otherwise only with ATC approval.

(e)The final approach trajectory should be intercepted no later than the FAF in order for the aircraft to be correctly established on the final approach track before starting the descent (to ensure terrain and obstacle clearance).

(f)‘Direct to’ clearances to a fix that immediately precede an RF leg should not be permitted.

(g)For parallel offset operations en route in RNP 4 and A-RNP, transitions to and from the offset track should maintain an intercept angle of no more than 45° unless specified otherwise by ATC.

ALERTING AND ABORT

(a)Unless the pilot-in-command has sufficient visual reference to continue the approach operation to a safe landing, an RNP APCH operation should be discontinued if:

(1)navigation system failure is annunciated (e.g. warning flag);

(2)lateral or vertical deviations exceed the tolerances; and

(3)loss of the on-board monitoring and alerting system.

(b)Discontinuing the approach operation may not be necessary for a multi-sensor navigation system that includes demonstrated RNP capability without GNSS in accordance with the AFM/POH.

(c)Where vertical guidance is lost while the aircraft is still above 1 000 ft AGL, the pilot-in-command may decide to continue the approach to LNAV minima, when supported by the navigation system.

CONTINGENCY PROCEDURES

(a)The pilot-in-command should make the necessary preparation to revert to a conventional arrival procedure where appropriate. The following conditions should be considered:

(1)failure of the navigation system components including navigation sensors, and a failure effecting flight technical error (e.g. failures of the flight director or autopilot);

(2)multiple system failures affecting aircraft performance;

(3)coasting on inertial sensors beyond a specified time limit; and

(4)RAIM (or equivalent) alert or loss of integrity function.

(b)In the event of loss of PBN capability, the pilot-in-command should invoke contingency procedures and navigate using an alternative means of navigation.

(c)The pilot-in-command should notify ATC of any problem with PBN capability.

(d)In the event of communication failure, the pilot-in-command should continue with the operation in accordance with published lost communication procedures.

RNAV 10

(a)Operating procedures and routes should take account of the RNAV 10 time limit declared for the inertial system, if applicable, considering also the effect of weather conditions that could affect flight duration in RNAV 10 airspace.

(b)The operator may extend RNAV 10 inertial navigation time by position updating. The operator should calculate, using statistically-based typical wind scenarios for each planned route, points at which updates can be made, and the points at which further updates will not be possible.

DESCRIPTION

(a)For both, RNP X and RNAV X designations, the ‘X’ (where stated) refers to the lateral navigation accuracy (total system error) in NM, which is expected to be achieved at least 95 % of the flight time by the population of aircraft operating within the airspace, route or procedure. For RNP APCH and A-RNP, the lateral navigation accuracy depends on the segment.

(b)PBN may be required on notified routes, for notified procedures and in notified airspace. RNAV 10

(c)For purposes of consistency with the PBN concept, this Regulation is using the designation ‘RNAV 10’ because this specification does not include on-board performance monitoring and alerting.

(d)However, it should be noted that many routes still use the designation ‘RNP 10’ instead of ‘RNAV 10’. ‘RNP 10’ was used as designation before the publication of the fourth edition of ICAO Doc 9613 in 2013. The terms ‘RNP 10’ and ‘RNAV 10’ should be considered equivalent.