Wind tunnel standardization disk drag
A 1936 NACA technical note, distributed through the NASA Technical Reports Server, presenting wind tunnel test data for a standardization disk used to check drag measurements. The plate shows two blurred, high-contrast photographs of a disk model in airflow, labelled Fig. 1 and Fig. 2, with faint reference grid lines; a designer might take from it the raw, degraded look of old aerodynamic test photography, with its heavy contrast and scratched texture.
