The issue of Air Spawns and Triggers
Typically when I build a mission my thought process goes as follows: Concept - Create Home Base - Create Target - Layout flight path using an AI - set enemy traps by laying triggers. Finally, I lay in two or three Air Spawns for those who have whoopsies, burned arses or "oh shits!". Generally I think, "Oh we'll have one here, one there and one over there" and that's it. And here lays the problem!
As a general rule I always design missions so that triggers are set off BY THE BOMBERS.
Ok so the mission is ready to test with the squad. As it progresses you notice that things aren't happening the way you imagined. Enemy planes keep spawning in where and when they are not supposed to. Why is this? Well, the problem often lies in the placement of the air spawns.
When a pilot gets shot down he re-spawns into an air spawn but if he chooses the wrong air spawn he will fly towards the action and may unwittingly set off a trigger that was intended to be set off by the bombers half an hour later. So now enemy planes are spawning in far from the action attracting the attention of the fighters who should be six grids further south.
So how do you guard against this? Well when you place an air spawn point think about the direction that the pilot is going to fly to get back into the action and in doing so, which triggers is he going to set off by mistake.
So try to place air spawns so that there is little or no danger of fighters flying into a trigger. Also if an air spawn is close by a trigger, set a "time out" so that the trigger will not be fired until the bombers get to it.
Another thing to try is set the trigger to be activated when the bombers enter their radii above or below a certain altitude. This can be done in low level missions also as the fighters will generally fly higher than the bombers and pass safely over the trigger.
There's no doubt that this is hard to do and there are never guarantees. You have to try and think of every possible scenario for each air spawn and find a way of guarding against an accidental trigger firing.
Mission Building Videos
There are many "how to" videos available on YouTube. I have suggested a few here but there are a lot to choose from. I also recommend checking out the Knowledge Base on the Mission4Today website.
I would like to give a special shout out to the YouTube contributers such as FlyingNutcase and Andrej Sygur.
How To, Tips and Tricks
A collection of thoughts and advice on mission biulding
FlyingNutcase - Manipulating Objects
Andrej Sygur - Airstart dogfight
Andrej Sygur - Taxi to Take-off
Andrej Sygur - Gliders to Take-off
Andrej Sygur - Creating Waypoints
Andrej Sygur - Formation
FlyingNutcase - Static Cameras
FlyingNutcase - Destruction Brush
FlyingNutcase - Front Line Marker
FlyingNutcase - Reacon Photo
FlyingNutcase - Trains
FlyingNutcase - Campaigns