[SNAFU]

I found this somewhere a while ago and just changed the timer for the AIAircraft:

public override void OnTickGame()
	{
   double initTime;    
		
    if (MissionTimer1M1.Elapsed.Minutes >= 59) 
		{
		MissionTimer1M1.Restart();
		foreach (int army in GamePlay.gpArmies())
            {
                foreach (AiAirGroup group in GamePlay.gpAirGroups(army))
                {
                    if (ActorName.MissionNumber(group.Name()).Equals(MissionNumber)) // Zeile L schen wenn auch AAA entfernt werden soll
                    {
                        AiActor[] members = group.GetItems();
                        for (int i = members.Length - 1; i > -1; i--)
                        {
                            (members[i] as AiAircraft).Destroy();
                        }
                    }
                }
               
    
			}
		}
	}
			
			//////////////////////////////////////////////////////////////////////////////////////////////////

    //Ground objects (except AA Guns) will die after 55 min when counted from their birth
public override void OnActorCreated(int missionNumber, string shortName, AiActor actor)
    {
        base.OnActorCreated(missionNumber, shortName, actor);
        if (actor is AiGroundActor)
            if ((actor as AiGroundActor).Type() != maddox.game.world.AiGroundActorType.AAGun)
                Timeout(3599, () =>
                {
                    if (actor != null)
                    { (actor as AiGroundActor).Destroy(); }
                }
                        );
    }

Note that you need to set the MissionTimer1M1 Stopwatch accordingly, f.e. in the OnBattleStarted-Section of you script:

using System;
using maddox.game;
using maddox.game.world;
using System.Collections.Generic;
using System.Diagnostics;

public class Mission : AMission
{
Stopwatch MissionTimer1M1 = new Stopwatch();

public override void OnBattleStarted()
{
base.OnBattleStarted();

MissionNumberListener = -1;
}
...
..
.


I found some issues with removing of the AI Airplanes, but these will be removed after landing by the standard remove-Ai-after-player-leaving script, so I left it that way. For ground units it works well.