Black smoke from exhaust

[blokovchan]

A lot of times I see a little of black smoke coming from my exhaust. It is not fire, no warning indicators are lighted.

 

Question is: am I moving throttle to abruptly ( I have Simple engine management on in options), or this is normal behaviour when power is somewhere near afterburn (I read this in some other thread...). Should this smoke disappear, when power is on full afterburner?

[Bogey Jammer]

A smoke puff comes out when the after burner switches off if I can remember correctly.

Old engine tech like this isn't perfect so I'd consider normal to see some smoke due to rapid changing conditions that the analog regulators can't catch.

[toutenglisse]

Yes it's very visible also with FC3 mig-29, sometimes there is a lot of unburn stuff coming out.

 

Same thing with diesel cars. Engines are "weighted" for moving parts to insure not too quick rotation speed increase, to limit the "unburn" fuel and the black smoke.