Check Navaid ID

I thought the ID flag in the NAV freq box signifies that the ID has been verified???   If not, what is its purpose?

Also the active freq switch occurs as soon as I activate the approach some 20 miles out.

So all the criteria is met, straight in to FAF, NAV id flag showing, ILS activated in FMS (not VTF but to the IAF), approaching FAF.

So it should show iSYR when ID'd?

Yes, I think so.  The "ID" on the right side is controlled from the Audio tab on the AUX page.  You turn off the ID mode to more clearly hear to a HIWAS or other voice signals over the VOR frequency.

How does the 540 know that I have manually checked the ID for the ILS?

I think you're telling the unit that you have identified the morse code audibly when you clear (CLR) that cyan message.

As the 540 switches automatically from GPS -> VLOC to GPS (as no VOR/ILS has been ID'd) when I get to the FAF, how do I suppress that?

Turn the mode knob one click to the right.

I can't get the iPad simulator to ever ID the ILS.  Does that sound right?

I haven't had much luck with VORs or ILSs in the simulator.

Auto-VLOC tuning is a user option which enables the automatic tuning of the active nav frequency slot to follow the governing navaid in the flight plan.

If the active leg is part of a VHF-based approach, the FMS will auto-tune the navaid that defines the final approach.

If the active leg is not part of a VHF-based approach, and if the active leg has a recommended navaid in the database, the FMS will auto-tune that navaid.  Otherwise, from the active leg, the FMS will look backward through the route and forward through the route for legs with a recommended navaid or that are defined by a navaid, in which case, the FMS auto-tunes the one of those two navaids that is closer to the aircraft.

The active IFD nav mode is displayed in green along the right edge of the top data strip.  The armed IFD nav mode, if there is one, is displayed in blue along that same top strip.  When there is an armed state, the nav source is depicted per the image below.

To trigger the transition from armed VLOC to active VLOC, all of the following capture criteria must be met:

·         The tuned frequency in the nav radio matches that of the approach navaid;

·         The Morse code decoded by the tuned nav radio matches the identifier of the approach navaid;

·         The aircraft track is within 15 degrees of the final approach course;

·         The course to the active waypoint is within 45 degrees of the final approach course;

·         The radio deviations are at most 50% of full scale for 5 consecutive seconds;

·         The active leg is part of the approach up to and including the final approach fix.

That makes sense.  Thanks

The last issue, again on iPad not sure if on real airplane, I have VLOC in yellow (manually forced it) but the airplane is following the GPS track to the missed and hold. 

Are you not using the dedicated traffic thumbnail data block?

That serves the purpose well enough for me.

David Bunin