Hi all

 

I have some questions regarding  procedures for RNAV and NPA approaches : 

 

the first time I've performed an RNAV APP, I did :

 

5 NM prior to FAF : 

* check RNP/ANP

* set MDA ALt on the MCP

* check VNAV/LNAV are armed or active

*Auto BRK set

* Spoiler Armed

* .........................................

 

at MDA I disengage the AP 

 

 

The other time, 5 NM prior to the FAF i did the same thing as stated above but I pressed the APP button, and I had FAC that was armed and so was the GP, the NGX performed then a kind of ILS APP,a bit like the VDEV and LDEV on an airbus. What does FAC means ? guess that GP means Glide Path. Also in the pmdg 777, even with an rnav approach selected on the fmc, if I press the APP button, nothing happens

 

So i was wondering if we have to press the APP button for RNAV app ???

 

 

Besides on the FMC, I saw VMC13L or something like that, what kind of approach is that : visual, Circling APP ??

 

 

Thanks

 

Camille MOUCHEL-BLAISOT

thanks

 

 

 

 

 

What does FAC means ? guess that GP means Glide Path.

 

FAC is Final Approach Course.  You have GP correct.

 

 

 

Also in the pmdg 777, even with an rnav approach selected on the fmc, if I press the APP button, nothing happens

 

This is correct.  The 777 is not a 737.

 

 

 

So i was wondering if we have to press the APP button for RNAV app ???

 

Depends on the type of approach you're doing.  If you look at the bottom of the chart, different minimums are listed.

 

Look at this chart as an example:

http://155.178.201.160/d-tpp/1406/05100R1L.PDF

 

LPV would be flown with APP (but could be flown in LNAV/VNAV, depending on the approved OpSpec - the main issue here is that the processing processes a narrowing lateral and vertical path, much like a LOC+GS).

LNAV/VNAV would be flown using LNAV/VNAV.

LNAV would be flown in LNAV/VNAV (for the 737 - this option is provided mainly for operators that do not have VNAV as an option, and would therefore use NAV + V/S or FL CH).

 

 

 

Besides on the FMC, I saw VMC13L or something like that, what kind of approach is that : visual, Circling APP ??

 

VMC means "visual meteorological conditions," so this would be a visual approach.  Selecting this option provides situational awareness only, and it should not be used to have the aircraft fly its course.  The approach should be conducted visually, and flown manually.

 

The chart for this approach is here:

http://155.178.201.160/d-tpp/1406/00610PARKWAY_VIS13LR.PDF

FAC - final approach course.

If you press APP button on non-presision approach you get LNAV/VNAV with ILS interface. That's called IAN. This is an option for 737/787 only. You can choose between them on your discretion depending what is said in charts and SOP.

VMC is visual meteorological conditions approach. To see whether it's circling or not preview it ot check charts.

 

Oops, I'm too slow in writing.

 

 

Oops, I'm too slow in writing.

 

...but the additional info is useful, especially because I didn't cover IAN, or convey that it's on the 737/787 only (for BOE models, at least)