GPS NAVIGATION

DISPLAY OF AIRWAYS ON THE FLIGHT PLAN PAGE

AIRWAY HEADING

When an airway segment has been inserted into the flight plan a white heading is displayed after the entry waypoint as shown in Figure 5-77.

Airway Identifier

Exit Waypoint

Identifier

Figure 5-77 Airway Header

Belowtheairwayheader,thewaypointsoftheairwayareindentedonespacetocreatesomevisualseparation between the airway and any subsequent off-airway waypoints that could be used on the flight plan. The PFD Flight Plan Window only displays the airway identifier and exit waypoint (Figure 5-78).

Airway Identifier

Exit Waypoint

Identifier

Figure 5-78 Airway Header on PFD

OPERATIONS USING THE CURSOR

1)On the MFD, bringing the cursor over the airway heading centers the map on the airway segment.

2)Pressing the CLR Key displays a prompt asking “Remove aaaaa.wwwww from Flight Plan OK or CANCEL”. If OK is pressed, the airway segment is removed (but not the entry waypoint). If the exit waypoint is the entry waypoint of a subsequent airway or if it overlaps an arrival or an approach, the exit waypoint is not removed.

3)‘Load Airway’ can be selected with the cursor over the airway heading. That brings back the Airway Loading Page which is initialized to the airway segment that is currently in the flight plan.

4)A new waypoint can be entered with the cursor over the airway header. The new waypoint is inserted ahead of the airway header (after the airway entry waypoint).

GPS NAVIGATION

COLLAPSE AIRWAYS FEATURE

‘Collapse Airways’ is selectable from the Flight Plan Menu if the flight plan contains at least one airway and the current state is “expanded” (Figure 5-79). In similar fashion, “Expand Airways” will be selectable if the flight plan contains airways and the current state is “collapsed”. When airways have been collapsed, it will be indicated on the airway heading.

Figure 5-79 Collapse Airway Feature

COLLAPSING AIRWAYS ON THE PFD FLIGHT PLAN WINDOW

On the PFD Flight Plan Window when the airway display has been collapsed, only the Entry and Exit waypoints of the airway will be shown. When collapsed format is active, leg-to-leg computed values such as DIS or ETE shown for the exit waypoint reflects the total of all the legs on the airway that have been hidden in the collapsed display. The DTK value is inhibited because its meaning is not clear in this context.

The “Expanded” format will automatically be selected after the “Load Airway” function is used (facilitates review of the flight plan).

ACTIVE LEG DISPLAY WITH COLLAPSED AIRWAY ACTIVE

The Flight Plan Page always keeps the following three waypoints visible:

•From Waypoint

•To Waypoint

•Next Waypoint (shows the next course)

To prevent one or more of these waypoints from being hidden in a collapsed airway segment, the airway segment that contains either the “To” or the “Next” waypoint will be automatically expanded.

INSERTING OPTIONAL AIRWAY WAYPOINTS

Occasionally, the pilot will need to be able to insert one of the “optional” airway waypoints into the flight plan. To make this easy, they are provided on a list like FPL, NRST and RECENT. The list is called AIRWAY. To add one of these to the flight plan, place the cursor over and left-click the FMS Knob, select the list which will have the desired waypoint, select one and press the ENT Key to insert it into the flight plan.

GPS NAVIGATION

Figure 5-80 Inserting Optional Airspace Waypoints

INSERTING OR DELETING OFF-AIRWAY WAYPOINTS WITHIN AIRWAYS

The pilot is always allowed to insert or delete waypoints within an airway segment. Except for inserting or deleting airway “optional” waypoints, it will usually have the effect of breaking one airway segment into two pieces. For example, consider the original airway segment as follows:

ABI

Airway – V16.TXK UKW

BYP

PRX

TXK

If “non-optional” waypoint BYP is deleted from the middle, the single airway sequence becomes two sequences because the resultant sequence UKW-PRX is now off-airway. The results are the same if an offairway waypoint is inserted.

ABI

Airway – V16.UKW UKW

PRX

Airway – V16.TXK TXK

Deleting the entry waypoint (ABI), creates a new entry waypoint and the airway header moves down as shown here:

UKW

Airway – V16.TXK BYP

PRX

TXK

GPS NAVIGATION

Deleting the exit waypoint (TXK), causes the airway header to change:

ABI

Airway – V16.PRX UKW

BYP

PRX

Since the exit waypoint of one airway is often the entry waypoint of the next airway, it is also possible that two adjacent airway segments can be modified when a single waypoint is inserted or deleted.

At minimum, an airway segment consists of two waypoints. The airway header is removed for any transaction that would create an airway segment that is not at least two waypoints long. For example, deleting UKW from the previous example creates ABI-BYP as an off-airway sequence ahead of a single V16 airway segment:

ABI

BYP

Airway – V16.PRX PRX

What happens if a waypoint is deleted from within an airway and subsequently re-inserted it into the original spot? The system does not restore the original airway arrangement. Continuing the previous example, re-inserting UKW restores the original airway waypoint sequence, but the Airway header does not get restored (the system sees UKW as just another off-airway waypoint that is being inserted):

ABI

UKW

BYP

Airway – V16.PRX PRX

Airway “optional” waypoints can be inserted or deleted in airway segments without breaking the airway into pieces. In addition, inserting or deleting a VNV ATK Offset waypoint is always allowed on an airway without affect on the airway.

GPS NAVIGATION

DIRECTIONAL AIRWAYS/INVERTING FLIGHT PLANS

Someairwayshavedirectionalrestrictionsonallorpartoftheroute. Airway“A2”inEuropehasadirectional restriction over the whole route such that it can be flown only in the direction MTD-ABB-BNE-DEVAL.

Airway “UR975” in North Africa has more complicated directional restrictions within the list of airway waypoints AMANO, VAKOR, LIBRO NELDA, DIRKA, GZO, KOSET and SARKI:

•Starting from AMANO, the airway can be flown only to LIBRO.

•Starting from SARKI, the airway can be flown only to LIBRO.

•Between NELDA and GZO, the airway can be flown in either direction.

The Airway Loading Page will be smart about these directional considerations so that only correct airway sequences can be inserted. If the pilot subsequently inverts that flight plan the system inverts the airway waypoint sequence but remove all of the airway headers.

NOTE: In the US, airways that are “one-way” for specified hours of operation are not uncommon. These airways will always be bi-directional in the G1000 database – this is an ARINC 424 limitation.

AIRWAYS AND DATABASE UPDATES

The G1000 allows saving stored flight plans with airways on them. When the database is updated, the airways will need to be reloaded in a fashion similar to what is done for departures, arrivals and approaches.

The basic process is that each airway segment is reloaded from the database given the entry waypoint, the airway identifier and the exit waypoint. This re-loads the sequence of waypoints between the entry and exit waypoints (the sequence may change when the database is updated).

If “optional” airway waypoints have been inserted within the airway sequence, those waypoints will be included when the airway is updated whenever possible.

The update of an airway can fail during this process. If that happens, the airway is removed from the flight plan. The following things could cause the airway update to fail:

•Airway entry waypoint or exit waypoint not found in the new database

•Airway identifier not found in the new database

•Airwayentrywaypointisnotanacceptableentrywaypointfortheairway–eitherthewaypointisnolonger on the airway, or there is a new directional restriction that prevents it being used as an entry waypoint.

•Airway exit waypoint is not an acceptable exit waypoint for the airway – either the waypoint is no longer on the airway, or there is a new directional restriction that prevents it being used as an exit waypoint (given the entry waypoint)

•Loading the new airway sequence would exceed the capacity of the flight plan