(Not) Taxiiing Using Crossing Runways

[Guest]

Recently at small airports with one long, one short crossing runways I find my aircraft permanently stopped behind stationary AI traffic queueing at the short runway, which ATC has told us to use to taxi to the longer active.As I've come across this problem twice now, at EGNJ and EICK, I am wondering if anyone knows a fix.I have tried adding a normal node close behind the hold-short node in AFCAD but that does not fix the problem. Aircraft, usually a small GA type, still get stuck permanently stopped there when told to taxi that route.Anyone know a fix?Peter

[Forkboy2 27]

Just take out the node that connects the crossing taxiway to the runway. You will get some runway incursions, but there really isn't any other fix, this is a limitation of the AI logic.Problem is that if there are aircraft in line to take off from a runway or land on a runway it is always considered active and no one can cross it. It doesn't have the ability to let aircraft cross the runway between departures.matt

[Guest]

>Just take out the node that connects the crossing taxiway to >the runway. You will get some runway incursions, but there >really isn't any other fix, this is a limitation of the AI >logic. Thanks for the reply. I'm not really sure what you mean though. It's the short and long runways that are crossing, not the taxiways.I have done some more experimentation. Since the shorter runway will never get used as such, as the AI logic always picks the longer as the active, I decided to think of it only as a taxiway. So I placed a hold short node on it 225 feet from the edge of the longer. That fixed the problem, at least as far as my testing went. AI aircraft now taxi to that hold short point on the short runway, request takeoff clearance then continue taxiing along the short runway, along the longer runway to the active end and takeoff. AI aircraft behind that one that has takeoff clearance hold short (on the short runway) until it has taken off. I don't know how that compares to "real-life" but its got my AI traffic in FS2002 moving again! The problem seems to be that the MS default hold short point was not within the necessary 225 feet of the longer, active, runway (EICK.)

[Guest Stamatis]

Matt,What you're saying is very interesting, I had not realized that sofar.So, taking EDDF (Frankfurt) as an example, if I use 07R only for landings and 07L only for takeoffs, my 07R landing traffic will never be allowed to cross 07L and taxi to the Gates, if I have a Hold Short node on the taxiway linking 07R and 07L, right before it enters 07L?Are you saying that this taxiway should be allowed to continue through 07L w/o a Hold Short node?Best RegardsStamatis

[Forkboy2 27]

As long as there are aircraft in line to take off (and I think even on final approach) then they will never be allowed to cross, assuming they are in the same overlay. It's not a problem at smaller airports that aren't very busy, but can be a problem at larger airports where there is always a line of aircraft waiting to take off.Matt

[Guest Stamatis]

So what you're saying is that as long as an aircraft is in contact with Tower, requesting Takeoff clearance, or on finals expecting to land, no ground traffic will be allowed to cross the active runway, correct?Stamatis

[Forkboy2 27]

The part about aircraft that have requested takeoff clearance for sure. The part about aircraft on finals I'm not 100% sure of.Matt

[tgibson 11]

The runway becomes uncrossable when a plane is cleared to land, not before that. The other time is when a plane is cleared to take off.Hope this helps,-- Tom GibsonCalifornia Classic Propliners: http://www.calclassic.com/Cal Classic Alco Page: http://www.calclassic.com/alco/Freeflight Design Shop: http://www.freeflightdesign.com/ San Diego Model RR Museum: http://www.sdmodelrailroadm.com/Drop by! ___x_x_(")_x_x___

[Guest Stamatis]

Hi Tom,"The runway becomes uncrossable when a plane is cleared to land, not before that."No comments on that, I have not observed much to be able to form an opinion of my own. "The other time is when a plane is cleared to take off."I will agree with Matt on this one.I have noticed that aircraft will never be allowed to cross a "takeoff only" runway as long as there are other aircraft waiting for departure. Even in the time between an aircraft's takeoff and before the next aircraft gets cleared for takeoff.Stamatis

[tgibson 11]

Sorry, I should have specified that my statement applies only to normal takeoff *and* landing runways from the same overlay.-- Tom GibsonCalifornia Classic Propliners: http://www.calclassic.com/Cal Classic Alco Page: http://www.calclassic.com/alco/Freeflight Design Shop: http://www.freeflightdesign.com/ San Diego Model RR Museum: http://www.sdmodelrailroadm.com/Drop by! ___x_x_(")_x_x___

[Guest]

Back with my original point, I 've found two alternative solutions so far. Anyone care to venture an opinion on which is more realistic?Recall the problem was getting AI traffic to use another connecting runway as a taxiway route to the active instead of, as it was, stopping permanently at that (other) runways hold-short point: -1) Add a hold-short node actually on the (other) runway at less than 225 feet from the active. Traffic then correctly requests takeoff clearance when stopped there.2) Deleting the node at the intersection connecting the two runway taxiways. There is then no possible route via the (other) runway. Traffic takes the much longer route back across the apron to another taxiway connected directly to the (far) end of the active. Aircraft given takeoff clearance there then take ages to taxi almost the entire length of the active before turning and taking off.Do aircraft use the length of "not in use" runways as taxiways (as per solution 1) in real-life?Rgds,Peter

[Forkboy2 27]

I'm not sure I understand your solution #1, but I will try that.I think the only solution for busy airports where this is a problem is just to remove the node that connects the crossing taxiway to the runway. A lot of places there is no other alternative taxi route. We just have to realize that there are some limitations to the AI logic. Having a runway incursion every now in then isn't usually a big deal, at least in the MSFS world. Once other thing I try to do is have the aircraft cross the active runway as far down the runway as possible so that the aircraft don't usually actually crash into each other. Matt

[Guest]

I had a similar problem taking off out of Ypisllanti MI at Willow Run Airport.I got around this by making a "new" taxiway ON the runway, (parallel to the runway nodes but slightly offset to one side). The aircraft taxi on the "taxiway" but appear to be taxiing on the runway.Check Six !!!!!Rick