Pioneer aviation engineer (1889–1972) who developed the first four-engine airplane and the first modern helicopter to be put into widespread use. Matte-finish 8 x 10 photo, signed and inscribed in black felt tip “To Rudy Koch with best wishes of I. Sikorsky, June 17, 1970.” A few creases, surface marks, and small marginal spots (most of which can be matted out), otherwise fine condition. R&R COA.
