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Localiser is offset - is there a "hack" for adjust

Jeff Clark

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Jeff Clark

Alberto Molteni and myself are trying to build some ACSim scenarios for Mumbai, as part of the Hit Squad project.


We've managed to get most things working, and the "heading" problem mentioned by others doesn't seem to be too significant for us (our magvar is only 1degree, and we're near the equator so perhaps we're lucky).


One problem we -do- have however is that when we instruct planes to join the localiser, it tracks a course which is about 10 degrees off from what the real localiser course actually is. The aircraft eventually makes it to the correct location at the threshold, but when further out, the difference in locations between the localiser and where the planes actually fly are significant - in some cases 2-3 miles off where the "extended centerline" is rendered by VRC - so I have two questions, "How does ACSim determine what the localiser course is supposed to be?", and what settings in the sector file could I "tweak" to get it to line up with VRC's extended centerline?


We've considered changing the magnetic variation but this seems to have little effect...


We've wondered if it was picking up extended centerline information for OTHER rwy 27's in the sectorfile, so we've tried deleting all rwy information except for the airport in question.


We're now at the point of wanting to try having two sector files - one that ACSim uses which is altered to correct for the error, and the real one used by the student controller - ACSim would drive the planes along the "artificial" localiser, which we've faked to follow a different heading, but we need to know how to fake that heading - it it generated simply using the 3 digit code in the rwy sector file? (Our sector file reads as follows), because when we tweak that setting, the localiser doesn't seem to shift... or is it done by somehow extrapolating along the LAT/LONG coordinates?


09 27 090 270 N019.05.15.651 E072.50.54.433 N019.05.17.628 E072.52.54.264 ;VABB Chhatrapati Shivaji Intl

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