Is there a way to reset the VNAV phase? For example if you were to 'accidentally' press '"DES NOW", is there a way to reset it to go back to VNAV CRZ?
Cheers.
Sure.
When you are in ACT DES, enter a CRZ ALT on the CLB or CRZ page.
When you are in ACT CRZ and you want to get into ACT CLB, enter a CRZ ALT on the CLB page.
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Thanks. I presume it only works if you enter a higher FL/ALT than you are already at.
Not when you want to get out of the DES.
I tested out pressing DES NOW when level in the cruise at FL370. VNAV then transitioned to the descent page as expected. With ALT mode engaged level at FL370 i then re-entered FL370 on the CRZ page and executed it. It just jumped back to the descent page. I tried also with the CLB page. It worked when I entered a higher FL than 370, FL380 for example. I was then able to enter FL370 on the CRZ page and continued on my way.
T
When your CRZ ALT is high enough and your distance to the destination is short enough, the FMC will activate the DES. You may get back into CRZ by re-entering the same CRZ ALT. But after a few seconds the FMC will re-activate the DES. This happens in the real FMC and therefore in PSX too.
In other words: When your new vertical geometry is such that the T/D is behind you, the FMC will activate the DES.
Cheers Hardy!
Hardy,
On some occasions - not all - i'm finding the FMC gets stuck in VNAV descent mode when executing a diversion to an alternate after a missed approach. I'm 51nm away from the diversion and only climbing to 8000ft. I go into the CLB or CRZ page and enter 8000 but it resets to the descent page again. I have found i'm able to put in a higher alt, say 9000, and it then resets to CLB phase. I can then re-enter 8000 and it's fine.
This doesn't happen that often but it has on some occasions.
I can't comment as I don't know your exact situation and what exactly you're doing.
It's not only about distance to destination but also about waypoint constraints etc. pp.