Grumman F8F

This is the only aircraft that I am aware of where the wing was designed to break at a certain point. Oscar "Pete" Erlandson, chief of Structures at the time, came up with a novel design that saved about 250 lb of wing structural weight. His wing design involved having wingtips that would break off when the fighter pulled about 7.5 g. A weak point in the design would allow the outer 3 ft to break off. An outer section of the aileron would separate also, leaving the wing with sufficient aileron control to make a safe carrier landing.

This design was not without problems. There was no way of insuring both wingtips would separate at the same time. There was a crash in December 1945 which was caused by only one wing tip breaking off. Finally in 1949 a service change provided strengthening of the wing tip to eliminate the break point.