"From Handling the Big Jets , by Dai 'The Book' Davies, ARB Chief Test Pilot: "It is wrong in principle to allow a swept wing aeroplane to suffer significant angles of sideslip". Good enough for me"
What do we PROFESSIONAL pilots call this principle..."The Because I Said So Principle." I want to hear it from the lips of a structures engineer, that "we didn't design the airframe to handle the stress of this manuever. I suspect this may be the case...at least over the long term.
Differences.....
Side Slip is a precision manuever to land when you have drift. You kill the drift with rudder and fly the appropriate amount of aileron to a landing. Here the wing gets dipped into the wind and you touch down on one wheel first.
Forward Slip is a nonprecision manuever when you need drag. It is an intentionally uncoordinated turn but you don't turn. You slowly feed in rudder and use aileron to level the wings. You keep your forward vector. The ailerons offset the rudder for zero turning effect. The vertical fin and fuselage are now exposed to the relative wind creating lots of drag. And I suspect, lots of stress.....more than Side Slipping anyways.
Which brings me to the reason for my post. Where am I in this stress envelope, when I forward slip at final appraoch speeds? This is the question which I submitted to Boeing. If they answer me, I'll post.