Descending with VNAV with PM

[captdave]

hello i have a stupid question

i make tests with PM demo. and planed a small route.
i flyed with vnav and lnav. and now the question:

how can i make a VNAV descend with PM?

with pmdg it was so, that when i reach the top of descend piont, i must tune down the alt and the pmdg was desceding automaticaly. but with PM the plane made it not automatic.

and the green fly status annunciator don't chance from CRZ to DES.

can somebody help me to undestand that?

[ralmav]

Hi,
you need to have an active flightplan in the PM-CDU.
Then, when in VNAV Mode on the MCP, if you tune down ALT, and reaching the TOD point, the plane descends automatically.

[captdave]

hmm mine don't do this.

what could be wrong

[Thunder175]

What aircraft model are you using when flying?

[Jackpilot]

In VNAV mode the MCP has priority
Ex:If you are level at 32000 feet you must dial a lower altitude such as 25000 before reaching the TOD point.
If in VNAV the aircraft will stay at 32000 until it reaches the TOD at which it will start a descent to FL250 or to whatever VNAV constraints between FL320 and 250
If the MCP dialed altitude is kept at 32000 it will not initiate its descent at the TOD point.

Maybe you know that already and it is something else ???

[captdave]

iam useing the modified pmdg 737-700 aircraft with the data.txt expecially for pmdg from PM homepage.

[flightdeck]

As far as I remember there is an entry in the PM MCP.ini which activates the VNAV descend ...

I may be wrong and I'm not in my simulator ... but it's worth for you to check !?!?!?

[dl4saw]

Hi,

nach allen Informationen (Bücher etc.) die ich kenne, muss man ein lower FL vor oder auch nach dem Erreichen des TODs einstellen. Der Flieger darf die CRZ-Höhe nicht automatisch verlassen. Genauso beim Steigen, darf der Flieger nicht über die am MCP eingestellte Höhe steigen, auch wenn die LEG bzw. CRZ Seiten so programmiert wurden. Dass der Fly-Status nich auf DES geht, ist ein bei PM bekanntes (und bestätigtes Problem).

Es gibt bei VNAV auch noch andere Fettnaepchen:
Die in der LEG Seiten angezeigten Höhen/Speeds für die einzelnen WPs werden nur dann zwingend eingehalten, wenn die manuell überschrieben werden. Dann sind die Zahlen ewas groesser dargestellt. Sonst darf der Flieger je nach COST-INDEX die Werte veraendern, natürlich nur in den für die einzelnen Flugphasen definierten Rahmen.

In mcp.in muss der Eintrag:
[VNAV]
DescentSpeedControl=on

Auch dann bitte aufpassen: bei VNAV descent, muss man, wenn "Retard" angezeigt wird, die Throttle auf Idle ziehen, sofern es nicht motorisiert ist.
Sonst gibt es Overspeed...

Gruss,
Geza

Sorry for the german language here, it was easier fo me...

[blueskydriver]

CaptDave,

You did not specify the versions of Flight Simulator you're using; is it FS9 or FSX. If you're using PMDG with FSX and PM, did you modify the PMDG Aicraft.cfg file once you put it into FSX. If you're using FS9 or FSX, these changes will remove PMDG from trying to control the Autopilot (MCP) functions.

If you're using FSX and PMDG with PM, just use the PM 737-700.txt and not the modified one for PMDG (from PM's website); that file was for FS9. You will come to find that PMDG in FSX with PM is not fool proof; you have to change things.

John

[captdave]

Ok i found the problem.

It was my eagerness

I was acclimatized with PMDG that the aircraft will go exactly into descend when it reach the T/D point.

But now i must wait some seconds more.
Sorry ..and thank you for your help!