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I'm getting really damn tired of all the smoke pouring out of all planes in X-plane 11 sim. and it does not help to press the "X" of the keyboard. Then there will be only twice as much smoke. So do something about the problem now !!!
You must wait for the new FX particle system to replace clouds, rain, smoke, contrails, etc per the head developer.
Search that page for contrails. Ben Supnik gives great details on what's to come post 11.0 for new FX engine.
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