Aircraft Operations

II-3-1-4
Procedures — Aircraft Operations — Volume I
An FMC using GNSS will contain either the three system modes of operation described above, or be required to
operate in conjunction with a flight director system or coupled autopilot system to ensure the required level of
performance is provided.
1.2.7 Course deviation indicator (CDI) sensitivity
1.2.7.1 The CDI sensitivity is automatically coupled to the operating mode of the receiver. Its settings are:
a) ±9.3 km (5.0 NM) in en-route mode;
b) ±1.9 km (1.0 NM) in terminal mode; and
c) ±0.6 km (0.3 NM) in approach mode.
1.2.7.2 Although a manual selection for CDI sensitivity is available, the pilot may only manually select a CDI
sensitivity other than ±0.6 km (0.3 NM). Overriding an automatically selected CDI sensitivity during an approach will
cancel the approach mode and approach mode annunciation.
1.2.7.3 Some FMC GNSS implementations may incorporate different display sensitivities for approach operations
from those shown above. These different display sensitivities may be used when guidance is provided by a flight
director or autopilot. Regardless of the approach display sensitivity differences between FMC GNSS implementations,
equivalent integrity must still be provided.
1.3 PRE-FLIGHT
1.3.1 Prior to IFR flight operations using basic GNSS receivers, the operator should ensure that the equipment
and the installation are approved and certified for the intended IFR operation, as not all equipment is certified for
approach and/or departure procedures.
1.3.2 Prior to any basic GNSS IFR operation, a review of all the NOTAMs appropriate to the satellite
constellation should be accomplished.
Note.— Some GNSS receivers may contain the capability to deselect the affected satellite.
1.3.3 The pilot/operator must follow the specific start-up, initialization, and self-test procedures for the equipment
as outlined in the aircraft operating manual.
1.3.4 For an FMC system, any special conditions or limitations for approach operations and alternatives will be
specified in the aircraft operating manual. One type may utilize steps identical to those described above. Other types
may require an operations control centre to perform an assessment of RAIM availability and provide this data as part of
the flight dispatch information.
1.3.5 For basic GNSS stand-alone receivers, the pilot shall select the appropriate airport(s), runway/approach
procedure and initial approach fix on the aircraft’s GNSS receiver to determine RAIM availability for that approach.
Air traffic services personnel may not be able to provide any information about the operational integrity of the
navigation services and approach procedure. This is especially important when the aircraft has been “cleared for the
approach”. Procedures should be established in the event that GNSS navigation outages are predicted or occur. In these
situations, the pilot must revert to an alternative method of navigation.
23/11/06