# VERTICAL NAVIGATION (VNAV)

### VNAV ALTITUDE WAYPOINT CONSTRAINT READOUT <a href="#vnav-altitude-waypoint-constraint-readout" id="vnav-altitude-waypoint-constraint-readout"></a>

* <mark style="color:red;">Displays an active waypoint constraint altitude automatically honored by the FMS prior to arrival at the preselected altitude.</mark>

![Ein Bild, das Tisch enthält.  Automatisch generierte Beschreibung](https://cdn.document360.io/417c2d4d-fdb8-4d4d-b11d-011fe445d776/Images/Documentation/primary-flight-display-pfd-image-r3m7i15a.png)

### VNAV TARGET ALTITUDE BUG <a href="#toc118376566" id="toc118376566"></a>

* <mark style="color:red;">Displayed when a VNAV target altitude is valid and the FMS is the primary NAV source.</mark>

<mark style="color:red;">Vertical Track Alert (VTA) is issued 60 seconds before the FMS commands a climb or descent, or 1.000 ft before the level off altitude.</mark>

### VERTICAL TRACK ALERT (VTA) <a href="#toc118376567" id="toc118376567"></a>

<mark style="color:red;">Is issued 60 seconds before the FMS commands a climb or descend, or 1.000 ft before the level off altitude.</mark>


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