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Guest are_62

VNAV - does not start descent

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Guest are_62

Hi there,I just bought Queen of the skies yesterday. It's awesome and I love it already.However... I have problems with VNAV (yes, I'm sure it's only user problems!). I can now program the FMC fine. The manual is fairly good but does not offer much for someone that doen't already know the functions of a FMC. I am a real life pilot but only single engine VFR so this is new to me.I can see the altitudes in the VNA pages in the FMC but when I get to the waypoints where it should start descent, it just keep going same altitude. I then click the Fight Level CHange button and can manually set it with the AP altitude control. I then switch it back to VNAV each time I reach a new altitude. But this can't be right?The other thing I'm not sure about is when the FMC tells me it needs drag... does that mean speedbrake?Does anyone have a tutorial that sets up and completes one flight from point to point? That would be very useful!Thanks in advance for your help Are

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>get to the waypoints where it should start descent, it just>keep going same altitude.This is happening because you probably have the current altitude set on the MCP panel and this prevents the aircraft to start descend. You have to set the MCP altitude to some lower value otherwise it won't descend. When MCP interfers with VNAV you would typically see "VNAV ALT" annunciated on the PDF as opposed to VNAV PATH if it worked as you would expect. The manual does tak about it.Michael J.WinXP-Home SP2,AMD64 3500+,Abit AV8,Radeon X800Pro,36GB Raptor,1GB PC3200,Audigy 2http://www.precisionmanuals.com/images/forum/747400.jpghttp://www.hifisim.com/images/asv_beta_member.jpg

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Guest pierre974

As Michal stated, do not forget to set a lower altitude on the MCP (in accordance with ATC's request).You also have to check the VNAV page in the FMC (page 3 - descent page), to set your descent average speed, speed restrictions and transitions.You can use VNAV or FLCH for the descent phase, then switch to V/S for lower rate of descent and sharp corrections...Hope this helps.Enjoy :-sun1

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Guest gremel

Also, I think you need to make sure that your altitude in the 'cruize page' is at your 'current altitude' you are actually flying at or VNAV will not engage for the descent phase. Then, enter the altitude/restriction that you want to descend to and push VNAV & it will then engage. I hope that all made sense..Regards,noullet

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Guest are_62

Thanks everyone - I tried what you suggested and it works. It was just that the AP altitude was set to the current altitude.Thanks again!

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