NACA Convertible Aircraft Reports & Zimmerman Flying-Wing Helicopter Proposals, 1945-48 (150 DPI)

A collection of PDFs covering early postwar American VTOL efforts. The first subject is a trio of NACA reports on various convertible aircraft concepts by de Monge, Leonard, Platt-LePage, Wilford, Wishon, and several other designers. The second subject is the Zimmerman Flying-Wing Helicopter, a modification of the Vought XF5U-1. Included are two proposal reports, correspondence, and a special set of 1/72 scale plans digitally traced from the original. In total, there are 128 pages of material with 31 pages of rare drawings, artist's impressions and photos scanned at 150 DPI. (Please note that the images are lightly watermarked with the Retromechanix logo).