A Low Density Material for Aircraft Structures

Extract

When the all-metal cantilever monoplane brought to a close the era of wood, tubes and fabric for aeroplane structures, the new development opened up broad fields for the improvement of aerodynamic efficiency, with resulting great increases in all-around performance, military effectiveness, and economy of operation.

The all-metal fuselage represented a new type of construction in that the skin formed a shell to replace trusses in carrying the bending loads imposed at the tail in flight and on the ground.The scheme of using a shell to give–at once–structural strength and aerodynamic fairing, previously accomplished by two elements, appears to be economical and sound. If the labour now needed for the fabrication and assembly of the multiplicity of internal members is to be eliminated the stresses must be taken in the skin and the principle should, if practical considerations permit, be extended to include the wing and fixed tail units.