elevator
Thanks PJ2,
On the structure we see an actuator fitting within its recess, and then immediately to the right of it, half the remaining recess with a hinge fitting (failure occurred at the recess itself), then open structure. According to the elevator diagram posted, there are two such adjacent actuator/hinge fittings on each elevator. That, and its size, would seem to indicate that the structure is part of the elevator.
-drl