VNAV

[pacificap]

Once I reach my top of descent I select a lower altitude on the AP window but VNAV disconnects by itself. FMC says CHECK ALTITUDE TARGET

Am I doing something wrong?

 

Edited November 27, 2017 by pacificap

[mmerelles]

You need to set the lower altidude before reaching T/D, the aircraft will start descending automatically at T/D