CBT_Phoenix

I was flying with ASP4 historical weather set at 23/12/2019, 22:00ish Zulu, and I was cruising at FL340. Instead I usually prepare for the arrival 100-150NM from tod (or last waypoint) and then I closely look to the instruments, so that when I'm about 50Nm from TOD I start lowering the altitude. This might be the cause, I'll try to reproduce the scenario with a lower cost index, as I usually fly with very high cost idexes (in this case was around 200). Thanks everyone!

Hi guys! I've been flying with the PMDG 737 NGXu for about a month now, and I recently had a problem with the CDU on the 737-900ER. I was performing a flight from KORD (FSDT) to KLAX (FSDT), with the latest AIRAC FMS data and charts. About 100NM before my last route waypoint I start setting up the arrival procedures in the CDU. The approach I used is ILS RWY06R, and the STAR is MDNYT2 (MDNYT2.06B) with HAKMN transition. When I go pressing EXEC on the CDU, it seems the aircraft cannot compute the SPD/ALT for the arrival waypoints and I get a "VNAV DISCONNECT" message. The only way I was able to perform the approach was to change to ILS RWY06R, FIN transition, and flying direct from HAKMN (last enroute waypoint) to FIN. Is there something I'm doing wrong or missing here? I'm relatively new to the 737, as I come from years of 777 so maybe there might be something different to do I'm missing out. Thanks in advance for any help! Giovanni