ILS approach minimums

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A2001

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While flying an ILS approach I noticed that my Garmin 430W stated LNAV in the bottom left corner. Normally it says LPV. On the approach chart, there are only ILS, localizer, sidestep and circling minimums.
Do I stick with ILS minimums, or do I have to use localizer minimums?
 
A2001 said:
While flying an ILS approach I noticed that my Garmin 430W stated LNAV in the bottom left corner. Normally it says LPV. On the approach chart, there are only ILS, localizer, sidestep and circling minimums.
Do I stick with ILS minimums, or do I have to use localizer minimums?
Click to expand...
What Approach is this?
 
Mongoose Aviator said:
You may need to switch the GNS430W from GPS over to ILS/VLOC once you are established on final approach. Some 430 unit configurations will auto switch (from GPS to ILS/VLOC) and some will not.
It sounds like you were still on GPS mode?

"If the CDI output has not automatically switched from GPS to ILS upon reaching the FAF, you must manually switch to the VLOC receiver by pressing the CDI key. Verify that “VLOC” is displayed directly above to the CDI key."
Click to expand...

I had it on Vloc mode and was getting the indications from localizer/ glideslope on my nav1 receiver
 
A2001 said:
KAFW ILS 16L
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I was wondering if this was one of those hybrid Approaches. It's not. I don't know the answer. But..I'm thinking the 430 detected that the Glideslope wasn't working so it threw LNAV up. Did you have a VOR/LOC Reciever in the plane? What was it showing? Were you getting Localizer and Glideslope needles?

EDIT: Just saw you answered that.
 
There is this note in the GNS430W Pilot's Guide & Reference.

Perhaps this is relevant?
Page i
"NOTE: GPS level of service annunciations (LPV, ENR, etc. as shown on page 83) are not applicable to the external CDI (or HSI) when VLOC is active."
 
Mongoose Aviator said:
There is this note in the GNS430W Pilot's Guide & Reference.

Perhaps this is relevant?
Page i
"NOTE: GPS level of service annunciations (LPV, ENR, etc. as shown on page 83) are not applicable to the external CDI (or HSI) when VLOC is active."
Click to expand...
Makes sense. Question is why does it annunciate them. Seems like it shouldn't. It's just distracting.
 
luvflyin said:
Makes sense. Question is why does it annunciate them. Seems like it shouldn't. It's just distracting.
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This is on the "Introductions / Cautions" page in the start of the manual and in fact is the last item.
Pure speculation but perhaps this was discovered at some point (well after GNS430W software development) and this was never intended to be doing this? Rather than fix this, an informational point was added to the documentation?
 
luvflyin said:
Yo, @midlifeflyer , what's going on here?
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An ILS is loaded, not an RNAV approach. Im pretty sure annunciating LNAV is standard when any non-RNAV approach is loaded. The approach is an ILS. You follow the ILS glideslope and green needles for lateral guidance on the FAS. The RNAV indication is irrelevant. The only distraction is thinking it means something other than "the GPS is at 0.3 lateral over here, so you are good on using it until the FAC and the missed." Absence would tell me it wasn't working properly.
 
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midlifeflyer said:
An ILS is loaded, not an RNAV approach. Im pretty sure annunciating LNAV is standard when any non-RNAV approach is loaded. The approach is an ILS. You follow the ILS glideslope and green needles for lateral guidance on the FAS. The RNAV indication is irrelevant.
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...well, to be clearer, mostly irrelevant. It can provide guidance for the initial, intermediate, and missed segments. It can identify step-downs and the MAP. And it provides situational awareness.

But the "LNAV" is just telling you it's there and the degree of tolerance.

Here it is on a GTN on a different ILS. Normal. (Avidyne is different)

IMG_2578.jpeg
 
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A2001 said:
While flying an ILS approach I noticed that my Garmin 430W stated LNAV in the bottom left corner. Normally it says LPV.
Click to expand...
To be clear: it only says LPV when on an RNAV approach which has LPV minimums. It should never say that when you load an ILS approach into the GPS.

Mark gave you the rest of the story already.

- Martin
 
Martin Pauly said:
To be clear: it only says LPV when on an RNAV approach which has LPV minimums. It should never say that when you load an ILS approach into the GPS.
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How would your statement then make sense of the note from the manual?

Mongoose Aviator said:
"NOTE: GPS level of service annunciations (LPV, ENR, etc. as shown on page 83) are not applicable to the external CDI (or HSI) when VLOC is active."
Click to expand...

As well as the screen shot of the simulator that was posted?
midlifeflyer said:
Here it is on a GTN on a different ILS. Normal.
Click to expand...
 
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