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jvile

Is runway choice solely dictated by AFCAD and wind in FS9?

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I'm having trouble with some of my addon airports. These are primarily high quality freeware airports (from FRF and Mach1 design) and some FlyTampa airports as well. Some airports I haven't detected problems with (yet, perhaps, I haven't tested them in all wind conditions).Yesterday for instance I did a flight out of KMIA to KJFK. The wind at KMIA was somethinglike 340 @ 12knots, yet aircraft were departing on runways 8L, 8R, and 12 which is completely asinine given the wind conditions.Are the runways used by AI traffic and assigned by ATC based solely upon the data found in the AFCAD file? If so, I'm going to need to start going into my AFCAD files and changing things, because this is beginning to drive me insane. I'm a real world pilot and seeing planes take off with a 15 knot tailwind is just not right and I need to fix it.Any tips on settings in the AFCAD (I've never edited one before) to make it so planes use a runway appropriate to the wind (and appropriate to aircraft size, don't want a 777 trying to land on a 4000' runway).

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FS9/FSX is far from being asinine when it pertains to runway selection. In most cases the problem is the User flying a plane vs a computer that has to simulate ATC.A simple example of runway selection in the code of FS is based on a scoring system. Runways are grouped such as KMIA if you are using a AFCAD that has my crosswind runway technique XML code in use. For each group of runways the following is computed using the longest runway of the group:Score = 0If runway length > 70% of longest runway at airport -> Score += 50Score += tailwind or headwind (tailwind < 0 and headwind > 0)If (unknown 'runway group' flag) Score += 10Score -= crosswindIf (runway landing==yes) -> Score += 100If (runway takeoff==yes) -> Score += 100The group with the highest score gets selected based on denial.The problem at this point is how did you go to KMIA. ATC cannot turn a airport based on winds if any type Plane (user or AI) is taking off or landing in the active visual airport scenery zone which for KMIA is 108 NM radius from the ARP.Based on your post I have to assume you were using a weather engine. Anytime winds change based on your default saved flight you must always reload the airplanes in the visual zone so ATC can flip the runway usage if the wrong ones are in use.Example1. Go To KMIA which will place you on a default runway.2. Now set your weather or load a 3rd party weather program3. Select "Go To" KMIA again and now choose what Gate you want to depart from. When you do this a black bar will go left to right and toward the end the AI Planes will reload using the correct runways based on winds.4. File your IFR FP The point here is to always reload the Planes after the weather engine is running so ATC can flip the runways if the wind vs runway selection is not correct.Another work around is once you have filed a FP and before contacting clearence go to the dropdown menu in FSX and select World|Map mode. In this window is a heading of your plane sitting on the ground. Change it by 1 degree. That will force a reload of FSX and once again sync winds and runway usage to ATC.B777If a airport has only one runway that is only 4000 ft long then FSX has no choice but to tell the B777 to land on it. The B777 will probably overrun the runway and who would develope a FP that sends a B777 into that airport to begin with.Landing Planes have a Empty Weight in the Aircraft.cfg file that ATC uses as a score to determine what runway will be used based on EW vs RWY length. If a airport has 2 runways and one is 4000 ft and one is 9000 ft then ATC is going to score the 9000 ft runway higher for all the arrivals including the B777. If a airport has a 4000 ft runway a 9000 ft visual runway and a 8500 ft default ILS runway with proper approach code in the XML database then the ILS runway as per ATC gets the highest score.These are just some very very simple logic codes that FS uses to score runways for proper selection.AFCAD or any Airport Utility cannot control what runway is the prefered based on a score. Airport Utilities based on the Designers knowledge can use my Crosswind code (introduced in July/2004) and make all runways active at one time. It is up to ATC to determine what type plane uses what runway based on a very complex set of codes in the .dll files.We the Pilot sometimes have to force ATC to flip a large Airport that has constant AI Traffic arriving if it is not our default startup airport. In some cases it may take ATC several hours to turn the airport around based on winds. The FSX wind code is a little better then FS9 but that can cause airplanes to takeoff in the opposite direction of the airplanes landing.Just remember to reload FS with a heading change in the menu after FS starts up (if needed) to sync runway usage to wind direction.

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