rsaleur

LPV not activated

Recommended Posts

Hi

I use RXP 430W V2 with Prepar3D V3, updated with the most recent Jeppesen database from my realworld Jepp subscription (I am a private pilot).

What I do not understand is why RXP 430W only sees RNAV approaches as "LNAV" while an "LPV" approach is available. Problem happens for example on European airports (LFPN, LFLA) while it seems to work normaly on an US airport (KHAO) with the same software and same database! Could the be a link with a pb of almanach data?

Thanks

Share this post


Link to post
Share on other sites
Help AVSIM continue to serve you!
Please donate today!

2 hours ago, rsaleur said:

Hi

I use RXP 430W V2 with Prepar3D V3, updated with the most recent Jeppesen database from my realworld Jepp subscription (I am a private pilot).

What I do not understand is why RXP 430W only sees RNAV approaches as "LNAV" while an "LPV" approach is available. Problem happens for example on European airports (LFPN, LFLA) while it seems to work normaly on an US airport (KHAO) with the same software and same database! Could the be a link with a pb of almanach data?

Thanks

Hi...

Just curious - can you post a link to the plates in question that has the LPV's for (LFPN, LFLA) - I can't seem to find them...

Regards,
Scott

  • Like 1

Share this post


Link to post
Share on other sites

Jean-Luc : Thanks for your suggestion, I will try it in a couple of days. I tried to launch the almanach update tool on my own with no success. Keep you informed.

Scottb613 : charts sent by private message. Would you try these RNAV approaches end keep my informed?

Share this post


Link to post
Share on other sites

Jean-Luc

I downloaded the two files you indicated me and copied them to the GNS trainer directory. Did not notice any difference, LFPN RNAV07 still shown as LNAV instead of LPV. It already tried to use the WFDEprdct application located in the same directory, no difference... Any other idea? I'm desperated...

Share this post


Link to post
Share on other sites
On 9/24/2018 at 5:37 AM, rsaleur said:

updated with the most recent Jeppesen database from my realworld Jepp subscription (I am a private pilot).

What I do not understand is why RXP 430W only sees RNAV approaches as "LNAV" while an "LPV" approach is available.

Do you mean in the real GNS, these LPV approaches show up when using this DB update, but in the simulated GNS, they don't?

However, LPV approaches for a US airport do show up as expected, just not the French ones?

Share this post


Link to post
Share on other sites

Hi Jean-Luc

Yes, my real GNS's (in my SR22) shows those RNAV approaches as LPV as they appear in my Jeppesen documentation, while they don't in the simulated GNS, using exactly the same db update...  I also tried with some other db versions downloaded from the internet with the same result, so it is not my JSUM-to-simulator import procedure wich is responsible.

I noticed this problem with French approaches but also other european countries incl Germany and Spain. In tried only one US approach (KHAO) which appeared as LPV correctly. Did not try other US approaches as I do not have up to date US documentation. But I can try some if you give a one or two working examples.

Buy feeling is that the problem is not related to the db but to the software of almanach.

 

Share this post


Link to post
Share on other sites

Jean-Luc

Still no solution to my problem. In order to investigate, could you please indicate me two US airports with LPV approaches (other than KHAO) and send me associated approach charts? So I may fully answer your questiuon ("However, LPV approaches for a US airport do show up as expected, just not the French ones?")

Regards

 

Share this post


Link to post
Share on other sites

Thank you Scott. I we be trying it and keep you informed.

For my information, where is the airport 4-letters identifier on this type of chart?

Share this post


Link to post
Share on other sites
1 hour ago, rsaleur said:

Thank you Scott. I we be trying it and keep you informed.

For my information, where is the airport 4-letters identifier on this type of chart?

Hi...

They're official US FAA plates so they just dropped the country identifier of "K"...

It's listed on both the top right and bottom right of the plate - next to the airport name...

In this case:

  • "MSV" = "KMSV"
  • "POU" = "KPOU"

Hope that helps...

Both are close to my home and I fly them regularly in sim and RW...

Regards,
Scott

Edited by scottb613
  • Like 1

Share this post


Link to post
Share on other sites
2 hours ago, scottb613 said:
  • "MSV" = "KMSV"
  • "POU" = "KPOU"

Either of those good for a $100.00 hamburger sim flight from the Baltimore area? Cafe/eatery?

Share this post


Link to post
Share on other sites
1 hour ago, fppilot said:

Either of those good for a $100.00 hamburger sim flight from the Baltimore area? Cafe/eatery?

Hi Frank,

Hmm - not really - if you're looking for immersion - KPOU is ORBX Freeware updated and while I did my flight training there - I don't recall having ever eaten...

KMSV - is default - and I find it difficult to use default airports... It’s my personal exception to the rule as that’s where I base my plane...

Place with the BEST food in the area - Nu Cavu - at the Wallkill Airport AKA Kobelt (N45) - but the default representation is pretty poor...

Not my PIX @ Kobelt:

on-the-patio-our-plane.jpg

 

Waterbury-Oxford (KOXC) might be a good dining representation - also improved by ORBX Freeware - 121 - a real sit down restaurant and probably worthy of the simulated AvGas...

Not my PIX @ Oxford:

Claris-121Rest-79-1200x800-c-default.jpg

 

Hope this helps...

:biggrin:

Regards,
Scott
 

 

Edited by scottb613
  • Like 1

Share this post


Link to post
Share on other sites
On 9/24/2018 at 5:37 AM, rsaleur said:

What I do not understand is why RXP 430W only sees RNAV approaches as "LNAV" while an "LPV" approach is available. Problem happens for example on European airports (LFPN, LFLA) while it seems to work normaly on an US airport (KHAO) with the same software and same database! Could the be a link with a pb of almanach data?

 

Hi,

Just as a reminder, RNAV GPS approach horizontal and vertical steering data are calculated in the receiver based on the aircraft and runway 4-dimensional location estimates. If the calculated z axis accuracy is reduced, generally due to GDOP, the receiver is required to step down from providing vertical guidance.  In that case it could annunciate LNAV instead of LPV at the FAF inbound.

When you say if "sees" RNAV approaches, can you please explain further "where" do you see this? Is this on the annunciator? Is this switching from LPV to LNAV at about the FAF? When it does, can you please go to the satellite page and check the VFOM (it should be below ~30ft)?

Edited by RXP
  • Like 1

Share this post


Link to post
Share on other sites

Jean-Luc  Thanks for those previsions. I am aware of this LPV to LNAV step-down mechanism and the location data precision requirements. When I mentin that the sim "sees" an approach as LNAV only instead of LPV I am talking about the RXP 430 window showing "LPV" ou "LNAV" in grren when crossing the FAF. It siimply switches from TERM to either LNAV or LPV. I never tried to check the satellite page but I will be trying.

Share this post


Link to post
Share on other sites

Scott : thank you for the KPOU and KMSV RNAV approach charts. It does not really help in fact because I can only fly it with :

- the "old" 2009 database imported from GTN650 emulator -> in this case there is RNAV app for KPOU and it works perfectly as LPV, but this does not answer by initial question which was "why are the French airports LPV approaches seen as LNAV with the very recent database I imported from my real world jeppesen subscription"

- the database from my real world jeppesen subscription -> it only contains european airports...

  • Upvote 1

Share this post


Link to post
Share on other sites

Jean-Luc : in each and every case (2009 or 2018 db, KPOU or LFPN), the satellite page show "3D Diff Nav, HFOM 16, VFOM 23 and EFU 0.03"...

Share this post


Link to post
Share on other sites
2 hours ago, rsaleur said:

the RXP 430 window showing "LPV" ou "LNAV" in grren when crossing the FAF. It siimply switches from TERM to either LNAV or LPV.

2 hours ago, rsaleur said:

he satellite page show "3D Diff Nav, HFOM 16, VFOM 23 and EFU 0.03"...

Even when it changes from LPV to LNAV?

 

 

Share this post


Link to post
Share on other sites
On 9/24/2018 at 7:55 AM, scottb613 said:

Just curious - can you post a link to the plates in question that has the LPV's for (LFPN, LFLA) - I can't seem to find them...

Looking into this issue, I've found these links for LFLA:

https://www.sia.aviation-civile.gouv.fr/dvd/eAIP_11_OCT_2018/FRANCE/AIRAC-2018-10-11/html/eAIP/Cartes/IAC/LFLA/AD 2 LFLA IAC RWY36 GNSS.pdf

https://www.sia.aviation-civile.gouv.fr/dvd/eAIP_11_OCT_2018/FRANCE/AIRAC-2018-10-11/html/eAIP/Cartes/IAC/LFLA/AD 2 LFLA IAC RWY18 GNSS.pdf

For any other french airport:

  1. https://www.sia.aviation-civile.gouv.fr/
  2. select "eAIP France" to the left
  3. select an effective date, this opens a new web page
  4. select "PARTIE 3 AERODROMES (AD)" | "AD 2 AERODROMES" to open the list of airports.
  5. select an airport in the list
  6. select "CARTES RELATIVES A L'AERODROME"

Share this post


Link to post
Share on other sites

I think I'm starting to get the "why", please correct me if I'm wrong.

Looking at the LFLA RWY18 GNSS and it mentions the 'EGNOS' channel used (Ch 41134). However, the GNS only has WAAS (at least software 3.30).

When trying a synthetic test on the trainer, anytime I make the LFLA RWY36 active, it disables 3D DIFF and reverts to 3D only in the satellite view page.

As far as I remember, there was a software update on the GTN recently (yes GTN) which mentioned something along the lines of not disabling GNSS approaches. As far as I know, the aviation DB includes 'feature' bits which disable specific approaches based on equipment, and reviewing the trainer bowels I think this is what is happening in the GNS.

Does this makes sense to you?

Share this post


Link to post
Share on other sites

Here are some advisories found:

https://www.garmin.com/en-US/aviationalerts/service-advisory-1029-rev-d-egnos-activation/

The combination of the EGNOS SoL broadcast and the database-enabled EGNOS capability facilitates the use of the EGNOS satellites in the navigation solution. The use of EGNOS will be transparent to the flight crew. Depending on certain criteria and available data in the navigation database, LNAV approaches augmented by EGNOS may provide advisory vertical guidance, which is indicated on the display as LNAV+V.

 

https://www.garmin.com/en-US/aviationalerts/service-advisory-1372-rev-b-unavailable-rnav-gps-approaches-due-to-lack-of-vda/

 A limited number of RNAV (GPS) approaches, including all service levels, are unavailable for selection when the approach includes LP minima and also has no published vertical descent angle (VDA).

This issue is resolved in the following software versions:

  • GNS 400W/500W Series main software versions 5.10 and later
  • GTN 6xx/7xx Series main software versions 5.13 and later

 

 

unrelated: DBs are growing in size so we'll be loosing more and more airports unless using regionalized DBs:
https://www.garmin.com/en-US/aviationalerts/service-advisory-1846-worldwide-navigation-database/

 

Share this post


Link to post
Share on other sites

Hi, we're making progress with this topic and I've created a new topic specifically about this prior releasing our next update:

 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now