How is active runway selected?

[moggel]

Trying to understand how the sim resolves the active runway on airdromes? One weird example is LTAF (Adana, Turkey). If I set wind > 0 kt runway 23 is used regardless of wind direction. But if I set wind = 0kt, runway 05 is the active.

Can someone shed some light on this mechanism? Is it possible to query which runway is the active (for AI) from Lua? If so, which code api is that?

[razo+r]

There are some mechanics at play. 

First, terrain. At some airports, one runway might never be used due to terrain around/behind, regardless of wind settings. 

Then, operational. Certain airports may use one specific runway at all times until the wind is above a specific threshold, where safety takes higher priority over operational concerns. 

And lastly, wind itself. Under ideal conditions, the runway in use will have as much headwind as possible.

However, if I understand your example correctly, it does seem like there is something weird going on, or not properly defined for DCS. 

Edited July 28, 2023 by razo+r

[western_JPN]

Some airports with X layout runways or triangle layout runways are more complex to decide the active runway(s) for takeoff or landing.

In Syria map, Beirut and Ramat David have such interesting but headache behavior with what wind is set in the missions.

 

[moggel]

10 hours ago, razo+r said:

There are some mechanics at play. 

First, terrain. At some airports, one runway might never be used due to terrain around/behind, regardless of wind settings. 

Then, operational. Certain airports may use one specific runway at all times until the wind is above a specific threshold, where safety takes higher priority over operational concerns. 

And lastly, wind itself. Under ideal conditions, the runway in use will have as much headwind as possible.

However, if I understand your example correctly, it does seem like there is something weird going on, or not properly defined for DCS. 

 

Yes, I can appreciate how it's done in the real world (there is also noise abatement to consider). But I'd like to know if I can use scripting to query which runway is in use at different airdromes. Since a script can't know all those real-world factors, or individual airdrome design, there should be some way to query what runway is the active for AI.

Edited July 29, 2023 by moggel

[Pikey]

On 7/29/2023 at 9:31 AM, moggel said:

Yes, I can appreciate how it's done in the real world (there is also noise abatement to consider). But I'd like to know if I can use scripting to query which runway is in use at different airdromes. Since a script can't know all those real-world factors, or individual airdrome design, there should be some way to query what runway is the active for AI.

 

There is no scripting for determining the active runway. Some are hard coded and the ones that aren't follow a rule of which way the wind is blowing to generate that. SInce you can get wind and you can observe the direction by watching AI, you can determine this like MOOSE scriopting does, but it involves work.

[moggel]

3 hours ago, Pikey said:

There is no scripting for determining the active runway. Some are hard coded and the ones that aren't follow a rule of which way the wind is blowing to generate that. SInce you can get wind and you can observe the direction by watching AI, you can determine this like MOOSE scriopting does, but it involves work.

Moose doesn't determine the active for AI. That mechanism is for players

[Lt.Turbo]

16 hours ago, Pikey said:

There is no scripting for determining the active runway. Some are hard coded and the ones that aren't follow a rule of which way the wind is blowing to generate that. SInce you can get wind and you can observe the direction by watching AI, you can determine this like MOOSE scriopting does, but it involves work.

There seems to be a threshold at about 6-8 knots where the AI will actually consider the wind for which runway is active. Anything less and they might take-off in the same direction as the wind is blowing instead of into the wind. 

[moggel]

On 8/19/2023 at 2:20 PM, Lt.Turbo said:

There seems to be a threshold at about 6-8 knots where the AI will actually consider the wind for which runway is active. Anything less and they might take-off in the same direction as the wind is blowing instead of into the wind. 

Yes, that is what I have concluded also. I have mainly been testing the Syria map so far so I can't say whether this behavior is consistently implemented throughout DCS, or if it's something the map designers do. But, so far, I've had to manually test each airdrome to see how it selects the AI active.

[Pikey]

On 8/19/2023 at 12:30 AM, moggel said:

Moose doesn't determine the active for AI. That mechanism is for players

Not true. Its been in MOOSE since 2018 at least and the active runway is what the AI use in DCS and what is given to players through the ATC system, as well as whatever ATIS class and so on uses. There are some rules, like you can't get it for multiple runway airbases and some unique issues like some airbases not having any runways, or fixed ones like Batumi. But what I said was still correct, in general, the wind tells you unless its one of the exceptions. The MOOSE AIRBASE util
https://flightcontrol-master.github.io/MOOSE_DOCS_DEVELOP/Documentation/OPS.FlightControl.html##(FLIGHTCONTROL).GetActiveRunway
can help you.

[moggel]

On 8/22/2023 at 6:51 PM, Pikey said:

Not true. Its been in MOOSE since 2018 at least and the active runway is what the AI use in DCS and what is given to players through the ATC system, as well as whatever ATIS class and so on uses. There are some rules, like you can't get it for multiple runway airbases and some unique issues like some airbases not having any runways, or fixed ones like Batumi. But what I said was still correct, in general, the wind tells you unless its one of the exceptions. The MOOSE AIRBASE util
https://flightcontrol-master.github.io/MOOSE_DOCS_DEVELOP/Documentation/OPS.FlightControl.html##(FLIGHTCONTROL).GetActiveRunway
can help you.

Well, you can get (and even set) the active but it is only accidental when AI actually uses it; it has no effect on AI as MOOSE cannot control that AI sub system. I also believed this was the case but testing it, with MOOSE, I realised it didn't work. I also asked about it and got an answer from MOOSE devs, confirming the function is indeed intended for players, not AI, like I said.

Edited August 25, 2023 by moggel