I'm not sure at the moment but there is still that "feature", even in 1.2, included that nullifies any thrust coming from a jet engine if a control surface is anywhere directly behind it. Not sure where the problematic range ends but it's quite far.
Is there any way to solve that with a mod or do we have to live with it / report it as bug just often enough? Or is there somewhere a answer that it is a feature that works as intended?