AD 57-04-01

57-04-01 CESSNA: Applies to All Model 310 Aircraft Prior to and Including Serial Number 35392, Except Those Incorporating Aileron Hinges Having P/N 0824006-1 and -2.

Compliance required not later than April 15, 1957, and at 100-hour intervals of operation thereafter. Inspect the outboard aileron hinge for cracks in the upper flange, adjacent to the bearing. Any hinges found cracked should be replaced with the new, redesigned outboard aileron hinge (P/N 0824006-1 left, and 0824006-2 right). When the redesigned outboard aileron hinge is installed, this special inspection is no longer required.

To facilitate hinge replacement, it is permissible to cut a standard size inspection opening in the wing lower skin, below the outboard hinge, attachment point.

(Cessna Service Bulletin No. 310-7 covers this same subject.)