Remove an A320 final discontinuity in MSFS 2020, fix NOT ALLOWED errors, and learn when vectors or end-of-route breaks should remain.
In Microsoft Flight Simulator 2020, open the A320 MCDU F-PLN page, confirm that the fix below FINAL DISCONTINUITY is the next fix you intend to fly, press CLR, then press the left line-select key beside the discontinuity. Insert the temporary flight plan if prompted. Do not delete a vectors or end-of-route discontinuity.
“Final discontinuity” usually means the last F-PLN DISCONTINUITY shown, rather than a separate Airbus discontinuity type. Its position matters: a break before a valid approach fix can often be closed, while one representing radar vectors or the actual end of the route should remain.
How do I clear the final discontinuity?
Select and verify the complete arrival before deleting the break, because clearing it instructs the FMGS to connect the preceding leg directly to the waypoint below it.
- Load the intended arrival. On the F-PLN page, select the destination and ARRIVAL, then choose the runway, STAR, approach and VIA or transition as required. Our complete A320 MCDU programming procedure covers the wider route-entry sequence.
- Inspect both sides of the break. Scroll to
F-PLN DISCONTINUITY. Confirm that the waypoint below it really should follow the leg above it; watch for duplicate fixes, a missing transition or a waypoint behind the aircraft. - Delete the discontinuity. Press
CLR, check that CLR appears in the scratchpad, then press the left line-select key aligned with the discontinuity. - Review the temporary route. If the MCDU creates a TMPY F-PLN, inspect it before pressing
INSERT*. Erase the revision instead if it produces a loop, an implausibly long leg or a route cutting across the arrival. - Check the Navigation Display. Use PLAN view if available and step through the flight plan. The magenta route should run continuously to the intended approach, with the active waypoint ahead of the aircraft.
The stock A320 and more detailed add-on A320s do not display every prompt identically, but the basic Airbus method remains CLR followed by the line-select key beside the discontinuity.
Should I delete every F-PLN discontinuity?
No—some discontinuities deliberately tell the aircraft that no computed lateral path exists between two parts of the procedure.
| Where the discontinuity appears | Likely meaning | Correct action |
|---|---|---|
| Between the STAR and approach | Missing or incompatible transition, or a direct connection requiring clearance | Reselect the arrival and approach first; clear it only when the next fix is the correct continuation |
| After a MANUAL or VECTORS leg | ATC is expected to provide headings or a direct clearance | Leave it in place until cleared to a fix, then use DIR TO if appropriate |
| Before the destination with no runway or approach loaded | The route is incomplete | Load the approach rather than connecting directly to the airport |
| At END OF F-PLN, below the destination, with no following fix | The actual end of the route | Leave it alone; it does not prevent the landing |
A mistake we see constantly is clearing every amber discontinuity simply to make the page look tidy. A continuous route can still be operationally wrong: deleting a vectors break may command an immediate turn towards an approach fix that ATC has not cleared you to use.
Why does the MCDU show NOT ALLOWED?
NOT ALLOWED means that the selected break cannot be removed in its present flight-plan structure.
- A MANUAL or VECTORS leg still separates the two computed legs.
- There is no valid waypoint after the discontinuity to connect.
- The break marks the end of the active flight plan.
- A procedure change has created duplicate fixes, an incomplete transition or an unresolved temporary flight plan.
- The imported route is malformed or exceeds what that particular A320 implementation models.
Do not delete the destination or random approach waypoints to force the message away. Reselect the runway, STAR and approach, check their transition, then review the sequence again.
An MSFS 2020 World Map route can also acquire missing or duplicated procedure legs when the arrival is changed in the cockpit. In that case, use our World Map flight-planning checks, or remove and rebuild only the arrival portion in the MCDU.
Can I use DIR TO instead?
Use DIR TO only when you genuinely intend to bypass the intervening legs, normally after an ATC direct-to clearance or when recovering a route after passing the active waypoint.
Select the intended fix on the DIR page, verify the proposed track on the Navigation Display, then insert it. DIR TO is not a cosmetic way of erasing a discontinuity: it can cut across a STAR, ignore altitude-planning assumptions and create a sharp intercept onto final.
Why will NAV not resume after clearing the discontinuity?
Clearing the discontinuity repairs the flight-plan sequence, but it does not necessarily re-engage managed lateral guidance.
- Confirm that no TMPY flight plan is still waiting to be inserted.
- Check that the active waypoint is ahead, not behind the aircraft.
- Look for a continuous magenta route on the Navigation Display.
- Check the Flight Mode Annunciator: if the aircraft remains in selected heading mode, NAV has not engaged.
If the active leg is unsuitable, use DIR TO for the next cleared fix rather than deleting more waypoints. Our Airbus managed-NAV and autopilot checks explain how to verify the lateral mode after correcting the route.