Ron,you don't need a course setting to be able to display an ILS localizer deviation. See here for an explanation of how it works:http://en.wikipedia.org/wiki/Instrument_Landing_SystemMartin

On the 747, the course is set in the FMC on the nav radios page (e.g. 110.10/072). I would expect the 777 to be the same.Martin

Thank you for the link.Then the COURSE setting seems to affect only the PFD centering indication but I'll check that next flight.Do you think they also phase the two signals as well for display purposes requiring the COURSE setting as a guide?I have been using the reciprocal COURSE on smaller aircraft for flying the outbound heading for a procedure turn, using HDG for the turn and setting the COURSE during the turn for inbound.(In another thread it is stated the 737NGs do not use PTs but I have located plates that show large turns to accommodate these heavier planes where terrain permits. Just including this before someone reintroduces this topic. Sometimes this is required for some ditch/canyon airports that require a descending hold or PT to get on the final vertical profile.)

> Then the COURSE setting seems to affect only the PFD centering indication but I'll check that next flight.As far as I understand the localizer needle on the PFD should be centered even if you've got the wrong course set. The only thing the course setting should affect is the orientation of the deviation bar in the EHSI. However, even this should display the correct deviation information if the wrong course is set (unlike with a VOR).> Do you think they also phase the two signals as well for display purposes requiring the COURSE setting as a guide?Sorry, not sure I understand what you mean here... as far as I'm aware, ILS (unlike VOR) doesn't use phase differences. It just looks at the difference in strength between the two beams -- if the two signals are of equal strength, you're right on the localizer.> I have been using the reciprocal COURSE on smaller aircraft for flying the outbound heading for a procedure turn, using HDG for the turn and setting the COURSE during the turn for inbound.I guess using the reciprocal course should be fine... since it's basically the same as flying the back course of an ILS...Martin