Decending in a HOLD

[Frank 737 0]

Captains, how do i get i done, to decend in a holding? Everytime i enter a hold nad then i enter a lower FL the CDU says, check mcp alt or check target alt. When i aktivate VNAV the bird doesnt start to decend. He keeps holding the actual ALT. Of course the mcp is set correct (to the new lower Alt). What am i doing wrong here? Greets Frank

[Vollie 11]

You do nothing wrong. Only what you have to do is to set the mcp alt to the alt you want to descend nothing else.Then the airplane descends and maintains the chosen alt.

[Vollie 11]

You do nothing wrong. Only what you have to do is to set the mcp alt to the alt you want to descend nothing else.Then the airplane descends and maintains the chosen alt-Check if the alts were filled in the fmc.-Check vnanv is on.-Wait untill airplane reachs the descent point (See on the NAV display).

[Spin737 102]

Where in the FMC did you change the altitude? Did you change it in the HOLD page?

[Frank 737 0]

Yes for both. I changed the alt in the cdu on the hold page, and of course i turned in the right alt on the mcp. But the plain doesnt decent....

[Spin737 102]

And what does the FMA say? ALT HOLD, VNAV ALT or VNAV PATH?

[Frank 737 0]

Vnav Path

[Vollie 11]

Where in the FMC did you change the altitude? Did you change it in the HOLD page?

Yes you must change it in HOLD page and than in the MCP.Look in flight plan map if the alt is set too. And also check the Descendpage. you can fill there an alt on the right sight.

[Techinica 0]

If you're seeing stuff about the MCP altitude on the FMC, its usually because the autopilot wants to desend below (or climb over) the altitude currently selected on the MCP. As you've seen, unless you drop the altitude on the MCP before the autopilot wants to start descending, it won't do it without you selecting the Altitude Intervention (small button to the right hand side of the MCP ALT selector knob).

[Frank 737 0]

I did everything, but the plain doesnt start decending. Is it possible to decent with vnav in a hold?

[Frank 737 0]

up

[Spin737 102]

Hmm. Shoulda worked. Try resetting your cruise alt, maybe.