Garmin:
The glide path that is generated is based on the information that is used for the Localizer Performance with Vertical guidance (LPV) and Lateral Navigation / Vertical Navigation (LNAV/VNAV) procedures. It uses a specified decent angle that is centered at the MAWP (Missed Approach Waypoint) and at the TCH (Threshold Crossing Height). If this information is included in the electronic database for the approach, the 400W/500W series, G1000 with WAAS, and GTN 600/700 series will generate a glide path.
What happens if someone flies a +V glidepath on a VOR approach with 7% CDFA?
Seems similar to the IAN we had on the 787, but there are probably a thousand unknown differences.
What happens if someone flies a +V glidepath on a VOR approach with 7% CDFA?
I assume nothing as long as you stay high above MDA: you can fly LNAV+V (or LNAV+5% or LNAV+7%), it’s a 2D NPA with one or few MDA, one can even fly exactly at those MDAs on Dive & Drive from FAF to MAPT and nothing bad will happen (Rod Machado in USA suggested we do this in his DVD), anything above that is a bonus, bellow MDA, it’s different: 7% CDFA, 5% CDFA or +V, you own obstacles and you avoid visually !
The only place where one has to watch “+V” is if LPV degrades to LNAV without the pilot noticing it: he will be “sitting between LPV DA and LNAV MDA on +V” which not a safe situation…
What happens if someone flies a +V glidepath on a VOR approach with 7% CDFA?
Obviously, many/most planes can’t fly 7% because of not enough drag even when everything is hanging out.
Otherwise, if you fly it right, it works.
However, this is off topic (completely irrelevant to equipment requirements!!) except that +V is available only on RNP (GPS LNAV) approaches, and to fly those you need an approach approved GPS – some background.
except that +V is available only on RNP (GPS LNAV) approaches
“+V” is available in every LOC, NDB, VOR approach I have flown on G1000W with GPS overlay, you get two lateral guidances one green & one magenta and one single magenta “+V” vertical guidance, you can even leave it to George to do procedural approach & procedural missed while you cross-check all sort of errors you could imagine: dme vs gps, green vs magenta, plate vs database, +V vs altitude/distance 
Even ILS, you can load it as “LNAV+V” and let George’s fly approach & missed but you won’t be able to show the green glide slope separately !
LOC altitudes & distances, ILS GP and +V GP do differ slightly
Snoopy wrote:
What happens if someone flies a +V glidepath on a VOR approach with 7% CDFA?
Will a nav box display a “+V” in such cases? Are you even supposed to fly a CDFA with a 7% descent path?
AIUI, +V is in the database only if a “GPS” approach is in there, so you won’t see +V on a purely VOR approach.
For that you would have to use some other mode of the navigator, and some (I am not up to date) have such features, which also enable totally-DIY approaches, possibly autopilot-coupled too. I am sure many here know the details. I have just the KLN94 
Garmin just says it’s a „specified“ glidepath. So I’m wondering if it’s always a 5% path to the MAP, even on say a VOR approach with 7% path. Could be dangerous…
There is no +V on a VOR approach.
Peter wrote:
AIUI, +V is in the database only if a “GPS” approach is in there, so you won’t see +V on a purely VOR approach.
Yes you will need “GPS” IAP overlay to be there (few VOR/NDB are not in DB due to huge offset, Jepps removed them)
If IAP is not in DB,
- If VOR itself is in DB, it’s not a show stopper you can set-up “CDI+VNAV” to any waypoint: you will have the final course but won’t have the missed
- If VOR is not in DB, you need to fiddle more, adding waypoint in DB is usually not a good idea…
1) Before anyone bangs on legality questions: it’s all legal for flying & cross-check, as long as you are “VOR equipped” and stick to VOR MDA, what you can’t do is use AP bellow 800ft agl on magenta line as it’s not AP coupled GPS/VOR approach !
2) The real question is why you are going to visit VOR/NDB in the first place? if you have GPS why not go straight to runway threshold, with 3D you know exactly where the runway sits up to 1 inch precision, it’s better than aiming for hill or forest where they put the VOR/NDB antenna then you fly a cross-country scud run to the runway threshold in low visibility, I think 2) is a better question than 1), it’s more practical one
Snoopy wrote:
So I’m wondering if it’s always a 5% path to the MAP, even on say a VOR approach with 7% path
There is no “official” Glide Path on VOR approach, there are 2D mandatory MDAs and altitude & distance profile to cross-check against
Same people still fly VOR IAP on Dive & Drive !
