47-30-03 CESSNA: (Was Mandatory Note 13 of AD-722-5.) Applies to All UC-78 and AT-17 Series Airplanes.
Compliance required prior to October 15, 1947.
Inspect the wing of 5,400- and 5,700-pound gross weight airplanes to determine that the wing has been properly identified as a 5,700-pound wing. The 5,700-pound wing has the following salient identification features:
(a) Laminated (8 to 10 ply) birch plywood reinforcement on the rear face of the rear spar (instead of spruce block found on the 5,100-pound wing) extending continuously through the center section from nacelle to nacelle. Ends of this plywood plate are scarfed out just inboard of each nacelle bearing block.
(b) Continuous plywood flanges 1 to 1 1/2 x 1/16-inch are found on both sides of the lower cap strips of wing ribs between the front and rear spars on 5,700-pound wings.
5/16 x 5/16 found in the 5,100-pound wing.
(c) The diagonal in nose ribs of the 5,700-pound wing is 5/16 x 7/16 insteadof 5/16 x 5/16 found in the 5,100-pound wing.
(Wings which cannot be identified as outlined above are not eligible for certification above 5,100 pounds gross weight.)