The runway excursion is another risk during runway operations (e.g. Toronto, Canada, 2005). To that end, AIRBUS proposes a Runway end Overrun Warning (ROW) and a Runway end Overrun Protection (ROP). ROW and ROP provide aural and visual indications when a risk of runway end overrun is detected during the landing phase.
In combination with ROW and ROP, AIRBUS also proposes the Brake-To-Vacate (BTV) function. BTV aims at optimizing the brake utilization and the passenger comfort when the flight crew selects a runway exit. Some ROW/ROP and BTV visual indications are provided on the OANS display.

5.1. DESCRIPTION OF OANS
OANS is a new system introduced by the A380. Its purpose is to locate the aircraft on an airport map displayed on ND. OANS generates the airport map with its own Airport Data Base (ADB). OANS improves the flight crew situational awareness during ground movements on airport surfaces (i.e. ramps, taxis, runways).

The expected benefits of OANS are to:
- Reduce the flight crew workload in the day-to-day task of navigating around complex airfields
- 
Contribute to safety improvement on airports that become more complex and busy

- 
Contribute to potential reduction of taxiing incidents

- Help preventing dangerous errors in surface navigation
- 
Reduce runway incursion occurrences

- 
Reduce taxi time, therefore fuel burn and emissions

- Integrate the Brake To Vacate (BTV) function.
5.1.1. OANS TERMINOLOGY
5.1.1.1. AIRPORT MAPPING DATA BASE (AMDB)
The Airport Mapping Data Base (AMDB) contains a set of graphical objects that defines one airport. The accuracy of AMDBs is approximately 5 m (16 ft).
5.1.1.2. AIRPORT DATA BASE (ADB)
The Airport Data Base (ADB) contains a set of AMDBs and customization settings
(i.e. AMI files). ADB is updated on a 28-day cycle.
Note: OANS does not provide information about temporary airport taxi restrictions. In addition, OANS may not display recent changes (new buildings or construction areas). Refer to NOTAM.
5.1.1.3. AIRPORT MAP
OANS displays on ND a background picture called the Airport Map. OANS constructs the Airport Map with AMDBs.

5.1.1.4. COVERAGE VOLUME
The coverage volume is a cylinder 5 000 ft
centered on the Aerodrome Reference Point (center of the airport map) with a radius of 20 NM and a height of 5 000 ft.

5.1.1.5. AIRPORT MAP DISPLAYED IN ARC AND ROSE NAV MODE
The airport map displayed in ARC or ROSE NAV mode is the nearest airport of either the departure airport or the destination airport (as entered in FMS). OANS determines the displayed airport with the coverage volume. If the aircraft is in the coverage volume of an airport stored in ADB, OANS displays the map of this airport.
5.1.1.6. AIRPORT MAP DISPLAYED IN PLAN MODE
The airport map displayed in PLAN mode is either:
　
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