Commercial Fixed Wing
Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Human-Machine Interface; Confusion
Aircraft Equipment Problem Less Severe; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Chart Or Publication
There is a fairly significant discrepancy between published runway heading and actual runway heading for ALW. On the ILS Z 20 and Jeppesen airport diagram it lists the runway heading and Loc course as 196. That is approximately 5 degrees off. The FAA airport diagram actually shows the proper runway heading as 201 but the FAA ILS Z chart still shows 196.This difference causes a noticeable issue with localizer capture; MFD course display and symbology. The autopilot and flight director struggle to initially capture and track the localizer because it is using 196 as a baseline; but that baseline should be 201. After a few minutes it will figure it out and not chase the localizer. This also causes an issue with the MFD course display because the displayed lateral guidance is actually at an angle to the displayed runway. In the FMS; it actually displays the proper course from CFFNW and RIRRO; but then defaults to the published 196 course. Finally; and my biggest concern; this causes the guidance cue to be shifted left of reality. It could be light winds and dead on the localizer and glide slope; but the flight path cue shows you pointed at the grass left and short of the runway.I'll note the RNAV approaches also show 196. I haven't flown that; so don't know how much of an issue it is there; but I imagine it could be there as well.Get the FAA to update the charting data! Kinda insane how their airport diagram shows the right heading; but nothing else does.
Air carrier Captain reported a discrepancy between published runway headings and actual headings that resulted in problems with localizer capture at ALW airport.