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MarvK

AI Question

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What would cause AI Aircraft to land 1-3 miles BEFORE the runway? Is it the .air file, flight plan, or the airport itself? Or maybe something else I'm not considering? It's a bit disconcerting to begin pulling onto the runway and have a B737 come screaming out of the weeds and onto the runway in front of me. :(

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What would cause AI Aircraft to land 1-3 miles BEFORE the runway? Is it the .air file, flight plan, or the airport itself? Or maybe something else I'm not considering? It's a bit disconcerting to begin pulling onto the runway and have a B737 come screaming out of the weeds and onto the runway in front of me. :(
Hi, This most often happens in the first 15 mins of a session while the AI engine sorts itself out.. Also having flightplans with altitudes of greater than FL400 can cause this as the decent profile is too steep for the sim to handle. I'm sure there are other reasons too...PeaceRen

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Hopefully there are some experts who will see this thread, but my impression is that the flightplan data includes the airport reference point and elevation which provide the initial aiming point for the the AI. When the AI get "in range" the airport facility data is read from the so-called AFCAD data, mainly the active runway position and instrument procedure (if any). AI fly a couple of different approach profiles:If flight plan is VFR and weather is VMC, AI will enter the pattern to fly a downwind/base/final sequence, based on the pattern direction and height in the AFD. I'm not sure if the weather is IMC, but I think the AI will disappear and reappear in parking.If the flight plan is IFR and and the weather is VMC, if there is an ILS approach coded the AI will follow the coded approach header data. If there is no ILS approach the AI will follow a "canned" visual approach. It seems like they will be vectored from either side or straight in depending on the geometry.If the flight plan is IFR and the weather is IMC, if there is no approach the AI will disappear and reappear at the parking. If there is any approach, the AI will use the highest priority approach, based on an internal priority list. ILS is the highest priority.These different approach methods result in different profiles, and the ability of the AI to properly follow them depends on the aircraft.cfg and .air files being realistic.From what I've seen (again I'm no expert) it seems like AI on IFR flight plan doing the visual approach have the hardest problem getting positioned correctly for a good landing. For sure many times they will fly through mountains if needs be.Edit: I should add that the traffictoolbox from the sdk has a couple of good tools for analyzing AI behavior. The explorer lists out the active AI, the flight phase they are in (sleep, flight plan, clearance, pushback1, pushback2, pre-taxi, taxi out, takeoff1, takeoff2, enroute, pattern, landing, rollout, taxi in). The map provides ordered heading/altitude and actual heading/altitude.scott s..

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Thanks for the info Scott. When I do see it happen, it's not IFR conditions. Doesn't sound like there's anything I can do about it. I just never noticed it this often before. I recently added a bunch of WOAI flight plans and models, so I thought maybe the .air file was off. I didn't notice it at all when I had Project AI installed.

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Thanks for the info Scott. When I do see it happen, it's not IFR conditions. Doesn't sound like there's anything I can do about it. I just never noticed it this often before. I recently added a bunch of WOAI flight plans and models, so I thought maybe the .air file was off. I didn't notice it at all when I had Project AI installed.
What you can do is use Jan Martins FDE sets. Many of the AI Plane models that WOAI package (plus others) fly well visually but are not tweaked very well for approaches/landings. Scott's post is very informative. AI planes approach/landing behavior is based on many varibles. The most common of all these varibles (planes land short) is when a airport is VMC and no ILS approach is available for the active runway in use. Scott explains this as a canned approach or also meaning no written instructions are available for the hardfloor of the FAF Terminal_Waypoint in FS. Now factor in poorly written FD's of certain AI Planes and they fall through the hardfloor on the approach and land short of the runway regardless of the rate of descent.If the airport sits on the cusp of the visual zone sector Country boundary this can cause within the first 15-20 minutes unusual AI Plane behavior on the descent. Many of the larger country's where the airport is inland to the country boundary work fine since the radius of the zone can be up to 125 NM's in distance (plenty of time for normal descent). The Explorer file when added to the module folder in FS helps in seeing how far out the Country Boundary is located in all directions. Airports like TNCM or LOWI can be a problem if the enroute flight level is set too high. If you see AI planes landing short always retest with an FS default type same size plane. This will help in showing which 3rd party AI Planes have problems and are canidates for Jan Martins FD sets.

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If flight plan is VFR and weather is VMC, AI will enter the pattern to fly a downwind/base/final sequence, based on the pattern direction and height in the AFD. I'm not sure if the weather is IMC, but I think the AI will disappear and reappear in parking.
From my observations, they get refused permission to land and keep asking at annoying intervals until they have flown right past the airport and out of radio range. I have no idea what they do next! Disappear into the sunset they can't see, I suppose!John

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