AMC1 NCO.IDE.A.195(a) Navigation equipment

CAA ORS9 Decision No. 47

Text in magenta in force from 30 October 2025

NAVIGATION EQUIPMENT — RNAV SUBSTITUTION

An RNAV system may be used to substitute for conventional navigation aids and radio equipment, without monitoring of the raw data from conventional navigation aids, under the following conditions:

SCOPE OF RNAV SUBSTITUTION

  1. RNAV substitution may be used in all the phases of flight except:

    1. to provide lateral guidance in the FAS of an IAP; and

    2. to substitute for DME, if a DME transceiver is either not installed on the aircraft or found to be unserviceable before flight.

SUITABILITY OF THE RNAV SYSTEM FOR RNAV SUBSTITUTION

  1. The RNAV system should meet:

    1. at least the requirements of (E)TSO-C129/-C196/-C145/-C146 (or later equivalent standards); and

    2. the requirements of NCO.OP.116(a) for RNAV 1, RNP 1 or RNP APCH as regards its installation in the aircraft.

OPERATING PROCEDURE

  1. The pilot-in-command is responsible for:

    1. ensuring that any procedure and waypoints used are retrieved from a navigation database which meets the requirements of NCO.IDE.A.205;

    2. verifying waypoint sequence, reasonableness of track angles, and distances of any overlay procedure used and in particular, where the use of RNAV substitution is used to replace offset DME with a zero-range indication, associated with an IAP;

    3. applying pre-flight procedures associated with GNSS use (e.g. RAIM check if applicable); and

    4. complying with any limitation on RNAV substitution in the AFM.

PILOT COMPETENCE

  1. The pilot-in-command should be aware of the limitations of RNAV substitution.

AIRSPACE LIMITATIONS

  1. RNAV substitution should not be applied on any procedure where RNAV substitution has been indicated as ‘not authorised’ by an AIP entry or a notice to airmen (NOTAM).

CONTINGENCY PLANNING

  1. Nothing in this AMC relieves the pilot-in-command from compliance with NCO.IDE.A.195(b) which requires sufficient navigation equipment to ensure that, in the event of the failure of one item of equipment at any stage of the flight, the remaining equipment shall allow safe navigation according to the flight plan, or an appropriate contingency action, to be completed safely.