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LNAV, PNAV, PRNAV, BRNAV, LPV, VPV - WTF does it all mean?

I quibble with using the term +V for the descent portion between RICHE and PENNE, this is using VNV, not +V

You are absolutely right, of course. The only “excuse” I could offer is that I was guided by two purple Vs

If you are in the Charlotte area, we should get together.

You might do it in March, perhaps….

I base my airplane at KUZA

N52 was the nearest field (looking around KUZA) with “just” LNAV+V approaches.
You are spoiled rotten by all those LPVs everywhere.

Last Edited by ANTEK at 31 Dec 03:54
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ANTEK,

That makes sense except I quibble with using the term +V for the descent portion between RICHE and PENNE, this is using VNV, not +V which is a WAAS term that applies to the LNAV+V advisory glidepath. The former is Baro VNAV, the latter is using GPS altitude.

Entered at RICHE. +V guided down to level off at 2500FT at PENNE.
GPS TERM to GPS LNAV+V when on final.

If you are in the Charlotte area, we should get together. I base my airplane at KUZA and live in Charlotte, NC.

KUZA, United States

The versions of VNV on the G1000 that I am familiar with, do not provide vertical guidance on the approach once past the IF and proceeding to the FAF.

I just “flew” the RNAV (GPS) RWY 4 approach to Waxham (N52), NC (in the Cessna NAVIII G1000 Trainer v8.01; running NavData file the same as yours).
Entered at RICHE.
+V guided down to level off at 2500FT at PENNE.
GPS TERM to GPS LNAV+V when on final.
Intercepted APR/GP at 2500FT over WIXXU.
“Manual” levelling off at 1040FT while on GP, 0.8NM from RW04.
All as per the current chart (SE-2, 12 DEC 2013 to 09 JAN 2014).

But the most important correction is that Australians don’t actually drink Fosters. We keep it to export to England.

Correcting the correction:
Foster’s Lager has been brewed in Europe for “centuries”.
Those of us, who migrated South quite recently, brought our bad European hobbits with us

Last Edited by ANTEK at 31 Dec 01:59
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No that was Antek’s description. It is a Meridian and I do mean the advisory glideslope not the VNAV. I will try it when back and confirm.

And Antek is right. I admit to being in holiday browsing mode so any ignoring is purely by accident!

But the most important correction is that Australians don’t actually drink Fosters. We keep it to export to England.

Last Edited by JasonC at 31 Dec 00:36
EGTK Oxford

Jason is not ignoring you, NCYankee!
It is a beautiful summery New Year’s Eve here.
Most likely JC is by the pool, sipping Fosters through a straw and minding the shrimps on the Barbie

Last Edited by ANTEK at 31 Dec 01:58
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JasonC,

For the third time, I ask what airframe are you talking about. You have ignored answering my question again.

Edit, I see ANTEK has answered my question. It is with the Meridian.

The VNV you are describing is not +V which currently only exists on LNAV final approach. The VNV is programmed into the flightplan and uses a Baro VNAV technique to make programmed descents. The versions of VNV on the G1000 that I am familiar with, do not provide vertical guidance on the approach once past the IF and proceeding to the FAF.

Last Edited by NCYankee at 31 Dec 00:19
KUZA, United States

I found mine would level off on a +V but not an LPV or LVAV/VNAV.

In all G1000/GFC700 installations I am familiar with the following happens:

During LNAV+V approach the autopilot will follow the +V advisory path, stepping-down to each +V advisory level in turn (provided VNV is enabled and the “assigned” ALT is set to below the final advisory level). If one wants the A/P to follow the advisory GlidePath, capture of GP must be enabled before the final track has been intercepted. When on GP (as when on the GlideSlope during an ILS) the autopilot WILL NOT LEVEL OFF regardless what the “assigned” altitude or baro-minimums (at References) have been selected. The only way I know of to make the GFC700 level off is to press the ALT button ….

Mine levels off based on selected altitude.

It must be someting special about Meridian then?!

Last Edited by ANTEK at 31 Dec 00:08
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Mine levels off based on selected altitude.

EGTK Oxford

I found mine would level off on a +V but not an LPV or LVAV/VNAV

What airframe? I have never seen this on the G1000/GFC700 systems for Cirrus, Beechcraft, and Diamond. How would the system know which altitude to level off at as this is not fixed for a given approach, for example different category aircraft, circling or not, remote altimeter, or other outages such as approach lights, etc. In the G1000 systems I am familiar with, the only level off is based on VNV prior to the IF or a selected altitude with VS or IAS (FLC) mode.

KUZA, United States

I found mine would level off on a +V but not an LPV or LVAV/VNAV

EGTK Oxford
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