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This question relates to the Flight Management System of a large airliner, e.g. Boeing 787:

During a flight, when the aircraft passes a waypoint, is this just passed waypoint (and the previous ones) still shown on the legs / FPLN page of the Flight Management System? Asked differently, can I scroll through all the past waypoints or are they automatically deleted once I have passed them?

Does the same apply to the Navigation Display (if I'd zoom out enough), would I still see all already sequenced waypoints and the past route, or do I only get to see the upcoming route and waypoints?

If they are not visible any more, why so?

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Previous waypoints are not shown on the 787's CDU, and only the last waypoint or PPOS (present position at which a direct-to was initiated) shows on the ND.

The 787 EFB does not show the plane position. Only very recently the FAA allowed own-ship display on moving maps.

As to why, there is no use for it. The POS REPORT page on the 787 would show the three waypoints needed for position reports (from, to, and next).

Some airways are one-way, so it's not like a U-turn will be needed (there is also no reverse sequence function). Any emergency gets priority and a direct-to the nearest suitable airport (weather and terrain permitting).

If the whole plan is needed (on display) for some reason, it can be reloaded as a secondary inactive route (if saved, or if can be requested via uplink).

On the MD-11, the progress page shows the last waypoint (singular), but not the 787, so minor differences can be expected. Above applies to the 787's route legs and progress pages.


Source: 787 FCOM.

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  • $\begingroup$ B737 and A320 FMS are the same. First line of the Legs page is the From waypoint (last leg). Previous legs are not retrievable. $\endgroup$ – Gerry Jan 15 '18 at 17:54

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