Strange behavior in cruise levels with MD-11

[Guest statikbuzz]

When in FMS INIT, I set cruise level in CRZ and complete setting the routes etc, everything seems to be fine. However, after flying two flights, both times in climb I've noticed that CRZ has been automatically changed to a higher value first time to FL345 (set FL340) and second time FL355 (set FL330), why is this? First time I was baffled for a long time, why the climb doesn't switch to cruise phase at all, next time already in beginning of climb I checked FMS and corrected correct FL, and flew happily to end.Is this a bug or something I just haven't understood yet?Regards, Jalmari Raippalinna

[mfrantz 45]

Jalmari,If you raise the altitude on the FCP (dial up the altitude knob) above the current CRZ LVL of the F-PLN INIT page, then (after a few seconds) the CRZ LVL will be raised as well to match the FCP altitude. I guess that this is what happened to you.

[Guest statikbuzz]

Oh, that how it works!It feels bit strange that vertical profile is changed just by accidentally rotating FCP altitude too high momentarily. Perhaps that is why I didn't realize what was happening. So while in CLB phase, if you rotate FCP Altitude too high just for a moment and then correct it back, you need to correct the FMC CRZ LVL or otherwise CLB never ends, interesting feature I say.Jalmari R.

[mfrantz 45]

Jalmari,This will not happen immediately. If you accidentally rotate the FCP altitude above CRZ LVL the CRZ LVL will not change for a few seconds, so that you have time to correct it back.