![]() If aircraft were limited to landing only when the weather was perfect, we would be flying a lot less than we do now! The ILS uses radio signals to help pilots align the aircraft accurately on their approach to a runway. Unlike your car, most aircraft are able to use a navigational system called the ILS. So how do pilots manage to land their aircraft safely and accurately without even being able to see where they’re going? Even driving a car can be dangerous in foggy weather. If MS had programmed the LOC capture routine so that it didn't have that ridiculous tendancy to start a right turn when it should be turning left, none of us would be here :( -DaiEDIT: Oops, see next post. I'm still open to suggestions on how to best to solve this problem. Back to square one or rather, back to trying to figure out when to turn into the localiser based on how quickly the FS LOC data (-127 to 127) is counting down.I'm trying to avoid the use of any of the GPS vars but it may come to that. It is headed for a point X somewhere on the localiser and the actual position of point X depends on the interception angle of the aircraft. It assumes that the aircraft is heading directly for the DME when it isn't. If MS had programmed the LOC capture routine so that it didn't have that ridiculous tendancy to start a right turn when it should be turning left, none of us would be here :( who responded:I have no idea if FS models offset LOCs but I'm using the following to plug in to the calculation:-sideC = (A:NAV DME:1,nautical miles)beta = abs((A:NAV LOCALIZER:1,degrees)-(A:PLANE HEADING DEGREES TRUE,degrees))gamma is being ignored as sin 90 is always 1.-which, of course, now I come to look at it after a couple of days I realise is completely the wrong calculation. ![]() Beyond that, if it were me, I'd hesitate expecting too much real world behavior given the simulation and database capacity of FS without trial and error who responded:I have no idea if FS models offset LOCs but I'm using the following to plug in to the calculation:-sideC = (A:NAV DME:1,nautical miles)beta = abs((A:NAV LOCALIZER:1,degrees)-(A:PLANE HEADING DEGREES TRUE,degrees))gamma is being ignored as sin 90 is always 1.-which, of course, now I come to look at it after a couple of days I realise is completely the wrong calculation. As Roman indicates, some may also be offset from runway center line. Is it an option to get into the gps database for distances? All the ILS's have Lat, Lon's in the gps database that can be used to calculate horizontal distance and if one of the airport altitudes is pulled, then slant line DME distance, too.Hope this helps,BobRegarding real world - from the small sample of fs9gps ILS's I've seen, all are indeed located beyond the far end of the approach runway. A/C positions left of the desired flight path are positive Cross Track values and right of the desired flight path are negative. ![]() If you're lucky, anyway.GPS WP CROSSTRK - distance the aircraft is from the desired flight path track, measured perpendicular to the desired flight path (I believe). Dai,Have you tried (A:GPS WP CROSSTRK, feet) ?I don't know if it works with an ILS track (that is, when aircraft navigation is controlled by NAV rather than GPS) or if it is really what you need, but in the xml world, I might give it a shot as it could turn out to be a simple way to get distance to localizer center line.
0 Comments
Leave a Reply. |