Aerodynamic Characteristics of a 4-engine Monoplane Showing Comparison of Air-cooled and Liquid-cooled Engine Installations
A 1939 NACA technical report on the aerodynamic characteristics of a four-engine monoplane, comparing air-cooled and liquid-cooled engine installations, issued for aeronautical engineers and researchers. The first page shows grid-plotted lift and drag coefficient curves against angle of attack, while the second shows wind tunnel photographs of a scale aircraft model mounted on struts, useful for designers wanting technical plate layouts and engineering diagram styling.

