I have noticed that the NAV database for my PMDG airliners includes some RNVM approaches. I assume that these are a type of RNAV approach, but when I try to use one in my 737NGX, the approach does not make any sense (it seems to double back on itself). I checked this out online, and it seems that WAAS is required to perform an RNAV GPS(M) approach (which is what I assume that RNVM is), so is this the reason why I am having problems with it? Any explanations by qualified observers would be greatly appreciated

Edited June 11, 20232 yr by Christopher Low

2 hours ago, Christopher Low said:

I have noticed that the NAV database for my PMDG airliners includes some RNVM approaches.

an example would help understand a complex "question" .... WAAS is not simulated to my knowledge, nor GBAS.

RNVM 02 approach at EGHI Southampton. My NAV database is actually six years old (the information supplied with the original PMDG 747-400 installation), so I do not know if this approach has changed since then. However, the official chart for the RNP 02 approach (from the NATS AIS website) seems to be very straightforward.

You might find this of interest (if you already have seen it, my apologies) -- https://www.faa.gov/about/office_org/headquarters_offices/ato/service_units/techops/navservices/gnss/nas/procedures/rnav_rnp

RNVM?  Never heard about it?

23 minutes ago, jcomm said:

RNVM?  Never heard about it?

Yeah, I have no idea what he's referring to. RNP? 

The approach options in the PMDG 737NGX FMC for EGHI Southampton include RNVM 02 and RNVM 20. I tried to find this on the internet, but the closest I could find is RNAV GPS(M).

1 hour ago, Christopher Low said:

The approach options in the PMDG 737NGX FMC for EGHI Southampton include RNVM 02 and RNVM 20. I tried to find this on the internet, but the closest I could find is RNAV GPS(M).

Exactly. Maybe it's a typo?

Something is amiss as there is only an RNP approach for Rwy 02. I would suggest it is a typo. I’m away from my PC at the moment otherwise I would check my nav data and take a look.

I assume that there is a file with all of this information located somewhere? If so, can anyone point me to it? Is it a config file?

PBN approach naming was a big mess back in days... since you are using a 6yo NAV DATA, that could be something as it is.....

14 hours ago, Christopher Low said:

I assume that there is a file with all of this information located somewhere? If so, can anyone point me to it? Is it a config file?

From memory it should be in your PMDG folder in the P3D root folder. It’s called Navdata. You can locate and edit the approach with a text editor like notepad or word pad. Needless to say just back up the file or folder first. 
Im home from this trip later  this morning so I will take a closer look then. 

I have looked at the files in that folder, but I cannot see anything with information regarding approaches. Maybe it is in a HIDDEN file?

6 hours ago, Christopher Low said:

I have looked at the files in that folder, but I cannot see anything with information regarding approaches. Maybe it is in a HIDDEN file?

No it's not hidden I just gave you the wrong location. You will find it in the PMDG folder but in the folder SIDSTARS and not NavData.

In the current cycle EGHI file you would find:

APPROACH RNV02 FIX BAMTU AT OR ABOVE 2500 SPEED 185 FIX HI02F 1700 RNW 02 TRK 019 UNTIL 3000

If all you want to do is change how the approach name appears in the CDU then just change RNVM to RNV02. The fixes may have different names and positions as well, as it is an old cycle you are using.
There is no RNAV approach for R20.

This is what I see in the SIDSTARS folder for EGHI Southampton. As you can see, it states RNVM02. This is followed by three transition options......

• APPROACH RNVM02 FIX FF20 AT OR ABOVE 1800 FIX MA20 890 RNW 02 FIX SAM AT OR ABOVE 890 TRK 200 UNTIL 3000 HDG 200 VECTORS
• TRANSITION D003L FIX D003L AT OR ABOVE 2300 SPEED 185 FIX NOVMR 2000
  TRANSITION NOVMR HOLD AT FIX NOVMR LEFT TURN INBOUNDCOURSE 183 ALT 2000 SPEED 185 LEGDIST 2
  TRANSITION SAM FIX SAM AT OR ABOVE 3000 SPEED 185 TRK 020 UNTIL 7.2 FROM FIX SAM

There is also an RNVM option for Runway 20.....

• APPROACH RNVM20 FIX FF20 AT OR ABOVE 1800 FIX MA20 890 RNW 20 FIX SAM AT OR ABOVE 890 TRK 200 UNTIL 3000 HDG 200 VECTORS
• TRANSITION D003L FIX D003L AT OR ABOVE 2300 SPEED 185 FIX NOVMR 2000
  TRANSITION NOVMR HOLD AT FIX NOVMR LEFT TURN INBOUNDCOURSE 183 ALT 2000 SPEED 185 LEGDIST 2
  TRANSITION SAM FIX SAM AT OR ABOVE 3000 SPEED 185 TRK 020 UNTIL 7.2 FROM FIX SAM