Wind/Slope and runway length entry.

[crashbar 2]

Hello,

  Well just like it sounds.  I'm hoping that I'm entering this in correctly.  For my flight winds were 70/10 local so I entered 10/.0 into the FMC.  Is this correct?  Also my runway was 12,400ft. take off length but i could could only enter 12 for 12,000.  It would not let me enter 124 for 12,400ft.  Is this also correct?  Any help/advice is greatly appreciated.  Thanks for your time, Dominick.

[Qavion2 39]

Dominick, windspeed entries would have to be based on the windspeed along the axis of the takeoff runway. e.g. A 10kt wind at 60 degrees to the airplane nose has only half the strength (so 5kts).  A wind at 45 degrees has only 70% of the strength, so 7kts. You may have to use trigonometry to figure this out. Make sure you don't have a large tailwind. There are limitations.

 

Where are you entering runway length? Which CDU page, side and line are you entering this?

 

Cheers

JHW

[Budbud 227]

Hi Dominick,

 

I would advise you to have a look at the FCOM from page 11.40.40 and onward. You will find here the answer to your questions.

[crashbar 2]

Budbud thank you so much.  What I thought was runway length is actually Position (POS) SHIFT.  Also 11.11.40 of the FCOM book exactly explains how to enter the WIND/SLOPE entry.  Thank you guys so much this really helps.

[Budbud 227]

The runway length or what i'm presuming to be is located on bottom right page of TAKE OFF REF page.

 

What you are referring to is the POS SHIFT entry. You don't enter the runway length here but the distance from the runway threshold in case of a takeoff from an intersection. It is used to update the position of the FMC when you push the TOGA button.

The FMC knows already the runway length from the data base.

POS SHIFT is mainly used if your GPS are dead. Otherwise you won't enter nothing here.

[pcubine 143]

Any help/advice is greatly appreciated

Runways in FSX and I assume P3D are level. There is no slope. If you want an accurate headwind use TOPCAT. Otherwise, just guess at it. Unless it is a strong headwind it's not go to make any difference. I don't make an entry unless the headwind is greater than ten knots. Then I would enter H10 or if the tailwind was 7 knots I would enter T07.