Originally Posted by
DaveReidUK
Quite so. After all, a fan isn't much more than a big prop.
In a typical high-bypass engine, the fan provides about 80% of the thrust, so Mr Newton tells us that liberated fan is only going to head in one direction (initially, at least).
As for the cowl, the intake lip diameter is typically less than the fan diameter, so a departing fan isn't going to leave the cowl behind, whether wobbling or not.
Broadly agreed and my knowledge of the coupling between angular momentum and linear momentum is far too stale to argue convincingly, but consider the hammer thrower in his cage. As a professional wobbler, he’s an effective converter of one to the other, albeit with no propeller attached! There surely was wobble here, however brief, and the last part of the fan case to let go might largely determine the ultimate trajectory, do we think?