Which approach were you cleared for? Which did you brief?
YOU fly an approach, using the guidance given by NavAids and the FMS. YOU decide whether or not the guidance is valid for the approach YOU are flying.
In the 744 and 748 you can manually "Park" (disable) the ILS; but why would you want to, if it is giving valid guidance for the approach? Even without IAN, the 744 will tune and capture the ILS when an RNAV or VOR approach to the same runway is loaded. It's not a new concept...
I see the ILS X Rwy 12 mins at KEAT as 318/1, and the RNAV (RNP) Rwy 12 as 769 / 2-3/4...
What are you currently flying? IAN should not be that much of a mystery. It's merely a slightly more automated method of flying non-precision approaches.
Last edited by Intruder; 21st February 2013 at 17:46.