What is the difference between a monocoque and semi-monocoque fuselage type?
A monocoque fuselage has its skin holding the skeleton structure together while the semi-monocoque has both the skin and the skeleton holding together. Semi-monocoque also has "stringers" running horizontally down the plane to help hold the frame together. The monocoque fuselage also cannot be used for airframes after a certain size (small aircraft with single engine), but the semi-monocoque has been used from single piston engines to commercial airliners.

A monocoque design would also have a safety risk involved if the skin was damaged because it is the load-bearing structure.



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