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FSX AI Plane Wont Land

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us-washington
Hi Everyone,

I have recently used ADE for edit the OR1J airport in Iraq (FSX). It was originally closed but used ADE to make it an open airport. I added some parking spots and the taxi ways for them as well as a runway link and a hold short taxi point. I created a taxi link to both ends of the runway with the south end having the hold short taxi link at the runway. I have checked my work a number of times using the FAULT FINDER and it says NO FAULTS FOUND. The problem I find though, is that after the first AI plane lands non of the other AI planes will land, they just continue to circle the airport. I'm adding a picture of the work I have done on the airport. I think it is a basic simple problem, there is probably something I am over looking. Any advice is welcome. As always thanks everyone for your help. This is a great forum and have found a lot of answers here.

hendrik357
 

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Once an AI aircraft lands, the runway is considered occupied until the aircraft crosses a hold-short node. You only have a hold-short node at the south end of the runway (Why?) That means if the aircraft approaches from the south, it will never encounter a hold-short node (until it takes off again) and the runway will remain closed.

Don
 
The rule is that EVERY aircraft taxiway connected to a runway MUST have a Hold-Short node within a short distance from the runway - the Hold-Short circle will tell you if it is within the correct distance. This will ensure that the rule mentioned by Don will be obeyed in every circumstance.

Ray
 
The rule is that each end of the runway that is used by AI, which usually means both, must have hold short nodes. Intermediate entrances do not need hold short nodes for proper functionality and you can test this. Consider that AI leaving the runway via any path will eventually pass through a hold short radius, if not directly over the node and this is sufficient to "open" the runway.
 
Every taxiway configured as a runway exit should have a hold-short node. Parking is assigned at the first hold-short node encountered by the AI aircraft. If the aircraft exits at an intermediate point that does not have an associated hold-short, normal parking assignment does not occur and the aircraft may
wander around the taxiway system looking for a hold-short node.

Don
 
Every taxiway configured as a runway exit should have a hold-short node. Parking is assigned at the first hold-short node encountered by the AI aircraft. If the aircraft exits at an intermediate point that does not have an associated hold-short, normal parking assignment does not occur and the aircraft may
wander around the taxiway system looking for a hold-short node.

Don

Absolutely! Couldn't agree more.
 
Absolutely! Couldn't agree more.
Good enough. Suggest you both review Don's tutorial.

Hold-Short Nodes – The MFS AI/ATC engine requires hold short nodes be placed to cover two
situations:
• each departing AI must encounter a hold-short node before entering the destination
runway; and
• each arriving AI must encounter a hold-short node before reaching its parking spot.
A single node may serve both purposes.
Hold-short nodes need not terminate the link leading directly from a RUNWAY-type link. There
may be several intervening links. The only firm positioning requirement is that hold-short nodes
for departures lie within 225’ (~70m.) of some point of the surface of the runway to which they
apply.
http://www.fsdeveloper.com/downloads/drive_through_parking_tutorial.pdf
Do you remember writing this, Don? On what basis would every exit taxiway need a hold short, if it was sufficient for all the taxi paths to cross through a single hold short on the way to parking?

This thread also has very pertinent information about hold short functionality and intermediate taxiways.

Hold Short Nodes on Runway Exits
 
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This item has nothing to do with "Drive-thru-Parking" as this is a different science compared to placing Hold Shorts in the normal manner.

If you only place H-S on the taxiways nearest the ends of a runway and there are no other taxiways leaving the runway then OK - no problems. What if you have a long runway that has, say, 4 more taxiways branching off the runway for arriving aircraft? Without H-S nodes in these taxiways, any aircraft landing and exiting the runway using one of these will not, under FS rules, be said to have 'left' the runway and further landing aircraft will not be able to land. It is very unlikely that this aircraft will get routed to either of the H-S at the ends of the runways in order to get to the parking spots so, effectively, the runway stays unusable to other aircraft. The aircraft will not get assigned to a parking spot and will likely, as Don says, go 'walk-about'.
This applies to AI aircraft not to a 'user' aircraft.
There are thousands of airports where it would not be possible to route all such taxiways thru a single H-S (remember that this H-S needs to be less than 225m from the edge of the runway). This would look like a very strange 'star-connection'!

Rick, if you can post an example of one of your airports (.ADE) where you have intermediate runway exits without H-S nodes, I would be interested to test it out for workability and, possibly, change my opinion on this matter. Always willing to learn from others.
 
This item has nothing to do with "Drive-thru-Parking" as this is a different science compared to placing Hold Shorts in the normal manner.
I feel very frustrated here. Did you go so far as to read the tutorial title?
Always willing to learn from others.
That is not overly apparent. Allow me to repost relevant sections in the hope that they are placed conveniently enough to be read. If they are, you will see that they have nothing to do with drive through parking.

Hold-Short Nodes – The MFS AI/ATC engine requires hold short nodes be placed to cover two
situations:
• each departing AI must encounter a hold-short node before entering the destination
runway; and
• each arriving AI must encounter a hold-short node before reaching its parking spot.
A single node may serve both purposes.
Hold-short nodes need not terminate the link leading directly from a RUNWAY-type link.

Ok, how many parking lots do you have, 2? 5? And how many taxiways? Why must a hold short be at the midway runway exit, when it is sufficient for AI to encounter one before parking, so long as that encounter is within 225' of a runway? Why would you need a "star" when these nodes can be placed anywhere within 225' of the runway and still not have to be at the intermediate exits?
How right you are, all my experience, tests and knowledge are the same.
Well, you don't provide any evidence you've read the linked thread above, small wonder, I mislinked it and it's fixed now. I trust jviles skill and experience and his anecdotes are worthwhile to be added to my experience and knowledge. I'll go ahead and quote:
The holdshort is not the trigger point to tell ATC that the next plane can land or not land. It is also not the trigger point for a airplane to be instructed to take the active runway for departure.

If the holdshort is not the trigger then what is. It is the runway texture. There are some hidden codes in a runway that many do not realize exist. What tells the Control Tower that a airplane has exited a runway is the contact points of the main landing gear. When the main gear clears the side of the runway texture that releases it from the control of Tower ATC.

Try one of these 2 test. Land your airplane to the side of a runway and Tower will tell you to immediately contact ground. Why, because Tower knows the wheels are on the ground but never sees them on the runway. End result is tower believes you have exited the runway when you never landed on it.

Another example. Many airport designers make a runway very narrow to try and hide the runway or make it invisible. If a runway is only 3 ft wide the main gear of a B737 never touches any part of the actual runway. Again ATC Tower tells the plane on touchdown to contact ground now. If by chance another plane is on final right behind you it is not told to go missed because tower thinks you have left the runway.

The same applies to a plane waiting for takeoff. If Tower thinks the landing plane is not on the runway for whatever reason (runway to narrow, plane landed to the side of runway) it now will instruct the waiting plane to taxi into position and takoff. There are situations where a landing plane is still in reverse thrust and rolling toward a taxiway exit and the next plane is already rolling down the runway for takeoff.

The holdshort node is a trigger where you stop to change to a ground freq. and not the point where ATC continues its cycle of departures and arrivals. The runway width in respect to main gear clearing the edge of the runway starts the cycle again for landing and departures.

I write a lot of curved approachs for runways. If I am not careful and the AI Plane cannot get on center line of the runway through the curve then big trouble. Any plane right behind the landing plane will also land with no go around instruction from the Tower.

You will see some of this behavior at any of the Kai Tak scenery's I have written the IGS 13 curved approach for (KaiTak1998 for FS9/FSX, KaiTak1963 for FS9, 9Dragons for FS9, FlyTampa for FS9/FSX, etc.)

hope this is helpful
As do I.
 
This will be my last post on this subject as Rick and I are not going to agree.
In my opinion what JV said about the runway texture being the trigger that says an aircraft has left the runway is for a USER aircraft. AI have to get to an H-S for FSX to know it has moved off the runway.
That is all I am going to contribute to this.
 
:redflag: Guys! This seems to be a situation when everyone is right (or almost)

Rick, I'm pleased that you've taken the time to read my tutorial. But nothing I said earlier in this thread is in conflict with it. If you want to configure your airport taxiways such that every AI will pass through a single HS node, by all means do so. But, in the real world, I doubt you'll find many runway entrances/exits where there is not a hold-short node. So, since most users are attempting to emulate the real-world, placing a hold-short node at each runway exit seems natural. Hence my use above of the word "should". But, of course, as you point out, they need not be there.

I value JVile's explanations (even though we did have the occasional "dust-up"). But, unfortunately, he's not here to clarify his explanation and to comment on Ray's suggestion (and my experience) that it applies only to user aircraft. Indeed, if JVile's statements apply equally to user and AI aircraft, then we still have no explanation as to henrick357's situation that started this thread.

Incidentally, hold-short nodes for triggering parking assignment (and possibly runway clearance) for arriving AI aircraft need not be within the Hold-short circle. They can be anywhere.

hendrik357, did placing a hold-short node in the taxiway at the north end of your runway resolve the issue?

Don
 
Sorry it has taken me a few days to get back to this page because I got lost. Don, I did add a Hold Short link to the north end of the runway but it didn't help. I removed that link and added a Taxi Link in the middle point of the runway and added a Hold Short link there at the runway. That got my AI planes to land. If one was a little too close behind another plane it did circle around but then did land and park. I'm not sure if in reality this is how it would be working. Thanks everyone for your ideas and advice. I will have another comment as soon.
 
A bit surprising that a hold-short midway along the runway works but one at the end doesn't.

For my own airports, I run a (narrow) blue taxiway line alongside the runway link which is connected to the runway link near every exit and at intermediate points and to every exit (with H/S) from the runway. This seems to guarantee the most efficient runway exit by AI.

Don
 
Sorry it has taken me a few days to get back to this page because I got lost. Don, I did add a Hold Short link to the north end of the runway but it didn't help. I removed that link and added a Taxi Link in the middle point of the runway and added a Hold Short link there at the runway. That got my AI planes to land. If one was a little too close behind another plane it did circle around but then did land and park. I'm not sure if in reality this is how it would be working. Thanks everyone for your ideas and advice. I will have another comment as soon.

Hendrik
have you checked that the hold-shorts are facing the correct direction? Dashed line nearest the runway?
 
Good morning everybody! And Happy Mother's Day too!!! I must have done something wrong before because I went back and added a hold short link to the north end of the runway and it did work. AI planes are now all landing as they should. If there is a plane coming in close behind another plane it does abort landing to do a go around but once the runway is clear it lands without issue. I can't thank you guys enough for your help but thank you!!!!

Now that I have this figured out (with your help) I need to go back and check a couple of airports I edited when I first started using ADE. It seems like they had the same problem. I will be able to correct my mistakes on them as well. I really enjoy using the ADE program.
 
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