Pioneer aviation engineer (1889–1972) who developed the first four-engine airplane and the first modern helicopter to be put into widespread use. Vintage 5.5 x 3.5 postcard photo of the Sikorsky S-43 in flight, signed in fountain pen, "I. Sikorsky, Dec. 15 1956." A touch of mild wear to edges, and slight irregularity to flow and adhesion of ink rendering signature somewhat light, but completely legible, otherwise fine condition. RRAuction COA.
