He is asking for a reference in the books.
So are you saying that the aircraft doesn't line-up with the localizer signal during decrab, but with the IRS track?
And that the aircraft track should therefore be within 5 degrees of the localizer course?
This sounds all highly unlikely, the IRS track is not the same as the aircrafts ground track it's only the calculated ground track. When locked on to the localizer you know you are following it's ground course, no matter what the IRS thinks.
So I guess it must be related to the IRS heading, not track. (the logic might be that if the track has drifted the heading might have drifted as well, and track difference is easier to spot As a symptom while on the LOC) Which could cause the aircraft not knowing where to put the nose during the line-up with the localizer.
But I can't find any reference for this.
Or is it simply that the LOC course has to match the rwy QFU? Which would then mean that the aircraft can perform an Autoland on a 5degree offset LOC (max Δ 5° with rwy QFU)? Which is unlikely and not something I would (like to) perform.
Last edited by 737Jock; 3rd March 2012 at 11:04.