Document ID: chunk:federal_register_of_legislation:F2018C00889:reg:5:p20
Version: federal_register_of_legislation:F2018C00889
Segment Type: reg
Provision Reference: reg 5 (pt 20/51)
Character Range: 78125–81030

cross-check of the flight plan by comparing charts or other applicable resources with the navigation system flight plan and the aircraft map display (if applicable);
(b) if required, confirm the exclusion of specific navaids.
Note   Small differences between charted navigation information and displayed navigation data may be noted. Differences of 3 degrees or less due to the equipment manufacturer's application of magnetic variation or leg track averaging are operationally acceptable.
       7.4 During flight, as far as practicable, navigation reasonableness must be periodically confirmed by cross-reference to available data from ground‑based aids, if available.
       7.5 For RNP 2 routes, 1 or more of the following must be used:
(a) subject to subclause 7.6 of this Appendix, a lateral deviation indicator;
(b) a flight director; or
(c) an autopilot in the lateral deviation mode.
       7.6 A navigation map display may be used instead of a lateral deviation indicator, if the navigation map display has functionality equivalent to a lateral deviation indicator as described in ICAO Doc. 9613, Performance-based Manual (PBN), Volume II, Part C, Chapter 2, Implementing RNP 2.
       7.7 Where a lateral deviation indicator is used, scaling must be selected suitable for the navigation accuracy associated with the route or procedure, for example:
(a) full scale deflection ±2 NM; or
(b) on an RNP 2 route using a lateral deviation indicator that complies with (E)TSO-C129 ( ) — full scale deflection ±5 NM.
       7.8 Route centrelines must be maintained as close as practicable, as depicted by lateral deviation indicators or flight guidance, unless authorised to deviate by ATC or under emergency conditions. Navigation System Error + Flight Technical Error (lateral deviation) must not exceed the specified navigation accuracy
       7.9 Brief deviations from the standard mentioned in subclause 7.8 of this Appendix are acceptable during and immediately after turns, but only to the minimal extent that accurate cross-track information may not be provided during the turn.
       7.10 If ATC issues a heading assignment taking the aircraft off a route, the navigation system flight plan may only be modified when:
(a) ATC clearance is received to rejoin the route; or
(b) ATC confirms a new clearance.

8 Contingency procedures for performance failure
       ATC must be notified immediately if the system performance ceases to meet RNP 2 requirements during an RNP 2 operation in controlled airspace.
Appendix 4 — Requirements for use of RNP 1

1 Eligibility for RNP 1 I.F.R. flights
       1.1RNP 1 may only be used for PBN by an aircraft that meets the requirements of this Appendix.
       1.2RNP 1 may only be used for PBN by an aircraft that has GNSS as the primary navigation sensor.
        1.3RNP 1 may be used by an aircraft which meets the aircraft eligibility requirements for