I am trying to make a blurr/heat effect for fighters and other AC but how do I make a .fx folder.

Its for jetliner though.

Any effect you download can be modified for any acft. Takes a little work but can be done. I do it all the time when I find a great effect I like and want to put it on another acft.

Usually requires several steps.

1] Figure out how the effect works, whether it is a "Light" Function, "Smoke" function or combination of both, OR gauge based effect (either normal gauge or XML)

2] Modify effect to "FIT" your acft. you are placing it on......this will sometimes require you to rename the effect files (.fx) to that particular acft.

3] Making the required entries to the appropriate .cfgs (Usually panel.cfg and possibly acft.cfg.)

There are many ways effects are generated. What and how you have to modify depends on the way the effect is generated.

Takes some tinkering to learn it as there is no ONE WAY to do it. Wished it was that simple.