Originally Posted by
Dave Gittins
Continuing my earlier questions …. if an electrical fault causes either a trim runaway (which can be stopped by pulling a couple of breakers) or no trim at all (breakers pop on their own) isn't the lack of a trim wheel something of an oversight ? Or do airworthiness considerations simply require two totally independent electrical trim systems fed from separate buses to satisfy the statistical unlikelihood of a double failure.
Appreciate if its FBW there may not be any (non electric) cables to attach to the pulley under the big wheel, so how do the trim wheels work on an A320 ?
actually, in a320 the trim wheel is the mechanical backup for pitch control.