Xplane C172 G1000 - KSNA 20R Approach Missing Waypoint and Altitude Different

Newbie Pilot - I have a subscription and updated to Rev 2202 rev 1 with FMS Manager to latest version of X-plane 11. Loading Approach for KSNA ILS 20R, I get this screen:

The altitudes for HUKEM and LEMON are different - as well as a missing waypoint DYERS which shows in the following latest approach plate:

I re-checked and checked the FMS Manager is up-to-date. I deleted the C:\X-Plane 11\Custom Data and re-uploaded from FMS manager, and verified its re-populated.

Shouldn’t this approach have the correct altitude restrictions and the additional waypoint? It has me questioning if the database is accurate or updating. Thanks!!

Hi,
first of all welcome at the “World of Navigraph” and welcome here in our forum. Thank you very much for this very interesting question.

This approach can flown as ILS or LOC approach. DYERS will only be used by the LOC approach but is not a part of the ILS approach. Jeppesen has coded this approach as ILS approach and therefore DYERS is not included.

The FAA charts are not so clear here but when you look on our Jeppesen chart you will find the following:

DYERS and D2.2 ISNA is only a part of “2” LOC only … When you would code a LOC approach, you need these two waypoints but Jeppesen codes this as ILS approach.

Hope that helps,
Richard

Fascinating. Thanks for the details! I am learning.
I am new here and specially just going thru instrument rating. So maybe it isnt a perfect world yet. – And another great reason to use the Jepp charts for accuracy.

Ok, so take a look at the altitude restrictions:

HUKEM shows 2200’ in the G1000, whereas Jepp shows 2800’. This is the weird one.

LEMON (faf) shows ceiling and base of 2200’, whereas Jepp shows 2200’ base not ceiling. (not sure that would matter here, also I could see where on the ILS this is the intercept point. So maybe this doesnt matter.

Also a good observation - I like so none standard questions :slight_smile: … thanks for that.

The is really a little bit special because HUKEM is the starting point of the final-approach and defined as FACF (final approach course fix). Also HUKEM has two altitudes - which are “between” value …

The correct definition is glideslope intercept altitude specified in second "altitude" (in this case 2200) and "at or above" altitude specified in first altitude (in this case 2800) on the FACF waypoint

It seems now that the Garmin shows you the second altitude, so the GS intercept altitude. I´m now not sure, if this is the same in an real-world Garmin, but when I check the data, you see both altitudes.

The yellow marker are the both altitudes - the red marker (J) is the “altitude description” flag which indicates what I have written before. So the data are correct so far and also complete according the charts. Again, I can´t really say, how this is showing in a real-world G1000 possible that´s a bug in the XP G1000 but to be sure, i would ask in the XP-forum too exactly with this example.

Sorry, that I can only check the data and these data seems to be correct so far.

Cheers,
Richard

Great information. I’ll check in a real G1000 and see what it does. It is very cool you can check the raw data. As I get into this, I may have to understand the file format and parsing parameters to be able to “debug” things like this in the future. Very cool! Thank you. This certainly eases any concerns that I might have interpreted the plate incorrectly and the inconsistencies in the simulator nav equipment too.

The conclusion is the Nav data to good. :slight_smile:

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