November 10, 201312 yr Hello, today I had a qute subtile issue with the great PMDG 777. I do not know if it is caused by a faulty operation by myself, a bug by PMDG or if it works as intended. Yesterday I flew from OMDB to EDDF with a 777F. PFPX suggested two step climbs, the FMC as well. I entered the step climbs as planned via /360S and /380S using the right LSKs on the LEGS page eventhough the calculations made by PFPX and by the FMC almost matched perfectly. Finally everything was working well. Today I was flying a much shorter route, namely from EDDP to EGNX. PFPX again calculated a step climb from FL360 to FL380, somewhat 300 miles before T/D, the FMC did not suggest a step climb. Anyway I entered the step climb by the fix PFPX suggested but the PMDG did not accept it. Strangely there was no error. I was able to enter /380S but the FMC still calculated FL360 for the following waypoints so it looked like this: WPT01 .840 / FL360 WPT02 .840 / FL380S WPT03 .840 / FL360 WPT04 .840 / FL360 and so on. The VNAV page still showed S/C at NONE. If I understand the FCOM correctly it should be possible to override the calculations of the FMC. A step climb was actually possible since the MAX FL according to FMC was FL382 from the beginning. What was really strange now that the FMC did not suggest a step climb eventhough the OPT FL on VNAV page was FL371. When I entered FL380 as CRZ FL manually the calculated fuel at the destination was about 0.4 tons higher so the higher FL has actually been more efficient. Furthermore the FMC did not show a recommended FL on the VNAV page besides OPT FL and MAX FL which it did yesterday when everything was working fine. I conjecture that this has something to do with the short length of the flight. But is this working as intended (e. g. no step climbs within 300 miles of T/D; I was not able to find something about that in the FCOM) or is it a bug? Did anyone encounter such a problem before? Regards
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