March 31, 20242 yr Since the new version with the PW engines, it does not appear to be obeying VNAV constraints correctly. For example with an AT OR BELOW FL230 and AT OR ABOVE FL190 it will level off at FL230. This was using a flightplan from SimBrief as follow KPHX/25R N0464F340 KEENS3 WLVRN DCT ESTWD HLYWD1 KLAX/06L using the BRUEN2 arrival at waypoint TRUBL
April 18, 20242 yr I have the same feeling. It's always getting high and fast for approach. I'm disengaging A/T when entering APP procedure and also selecting AT, instead of AT or ABOVE, at altitude constraints for final approach fixes.
April 20, 20242 yr You do realize that FL230 is at or below FL230 and at or above FL190. Your description of the behavior is not a problem. Looks like you expected it to do something else. Not only is the plane looking to hit constraints, but it is calculating the path for the next constraint. I flew that arrival, and it did what was expected. Mark "Crabby" Crabtree AAL311 | PHL 7800X3D | 5070 TI | Honeycomb Alpha/Bravo | MFG Crosswind
April 22, 20242 yr Exactly I did what it was supposed to do. You can also manually hard select a specific altitude between the two altitudes. However you observed normal behavior.
April 23, 20242 yr FWIW--With the latest update (~ 2 weeks ago), the aircraft blows through ALL altitude constraints on the DP/SID for EGLL 27R. This occurs with the altitude constraints set as "AT' rather than "AT+".
April 23, 20242 yr 3 hours ago, rlw9sr said: FWIW--With the latest update (~ 2 weeks ago), the aircraft blows through ALL altitude constraints on the DP/SID for EGLL 27R. This occurs with the altitude constraints set as "AT' rather than "AT+". Nothing wrong with that - its flight computer doesn't respect departure restrictions in reality. Edited April 23, 20242 yr by LukeFF
April 25, 20242 yr VNAV is definately messed up. If you edit the descent constraint at FL100, even though the FMC shows the speeds updated to the new speeds, the speed set by the autopilot is still set to 250, at least until the first WP after FL100. I already manually set the speed to 230, so not sure if the FMC updated the speeds after the fix or not.
April 25, 20242 yr 43 minutes ago, ab145 said: VNAV is definately messed up. If you edit the descent constraint at FL100, even though the FMC shows the speeds updated to the new speeds, the speed set by the autopilot is still set to 250, at least until the first WP after FL100. I already manually set the speed to 230, so not sure if the FMC updated the speeds after the fix or not. If you can see the speed in the window and not dashes ---, then you are controlling the speed, and you would have to dial it back and follow the speed limits from charts or what you set. Mark "Crabby" Crabtree AAL311 | PHL 7800X3D | 5070 TI | Honeycomb Alpha/Bravo | MFG Crosswind
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