Torsional Stability of Aluminum Alloy Seamless Tubing
This NACA technical note from 1939, issued by the National Advisory Committee for Aeronautics in the United States, reports engineering tests on aluminum alloy tubing for aircraft structures, written for aeronautical engineers and researchers. Its pictures are plain graph plots of buckling stress against tube length and diameter ratios, plus one photograph of buckled tubes, so a designer might take from them the clean line-graph conventions of technical engineering publications and the stark, grey photographic record of structural failure.
