- 
The default airport determined by OANS.

The default airport is either the departure airport or the destination airport. OANS determines the default airport as the most suitable airport according to the following parameters:
- 
The distance between the departure and destination airports

- 
The distance between the aircraft and the departure or destination airport

- Before or after the transition to the FWS CRUISE phase (i.e. 1 500 fr or 2 min after lift off), particularly for proximate airports (less than 300 NM).
5.1.1.7. MAP REFERENCE POINT
The Map Reference Point is the reference point to center the airport map when the flight crew selects the PLAN mode. The Map Reference Point is:
- Either the Aerodrome Reference Point when the aircraft is airborne, or
- The current aircraft position when the aircraft is on ground.
5.1.2. OANS PRINCIPLES
5.1.2.1. AIRPORT MOVING MAP
OANS displays an Airport Moving Map on ND at the discretion of the flight crew in ARC, ROSE NAV or PLAN modes. The displayed airport may be:
- Either manually selected by the flight crew (in PLAN mode only), or
- Automatically selected by OANS from either the departure airport or the destination airport entered in FMS.
The Airport Moving Map includes comprehensive information about:

.  
Runways: QFU, stopways, thresholds, centerline, intersections, markings, exit lines, shoulders, LAHSO markings, etc

.  
Taxiways: taxi identifiers, guidance lines, holding positions, shoulders, etc

.  
Aprons: parking stand areas, parking stand locations, stand guidance lines, aerodrome reference points, de-icing areas, etc.

Thanks to a GPS/IRS hybridization, OANS locate the aircraft on the Airport Moving Map with an accuracy of:
- 10 m (33 ft) for the position
- 0.4° for the heading
- 0.5 kt for the speed.

The flight crew interacts with OANS through:
.  EFIS CP:
- 
To select the display mode (ARC, ROSE NAV or PLAN)

- 
To activate the OANS display on ND (EFIS CP range selector on ZOOM position)

- 
To select the display range (5 NM, 2 NM, 1 NM, 0.5 NM, 0.2 NM).

.  KCCU:
- 
To select an airport

- 
To navigate throughout the Airport Moving Map (drag technique)

- 
To set some marks (flags and crosses) for drawing a path

- 
To activate the correct database.

Refer to 5.1.4 – OANS Controls for details.
5.1.2.2. APPROACHING RUNWAY ADVISORY
OANS triggers the APPROACHING RUNWAY advisory each time the aircraft approaches a runway, a runway intersection, a displaced area, or a stop-way. The APPROACHING RUNWAY advisory is a pulsing message with the name of the runway (refer to 5.1.3.5 – Approaching Runway Indication).
　
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