Igor Sikorsky test flying the VS-300 helicopter in 1940.
<video controls autoplay loop> <source src="https://diqn32j8nouaz.cloudfront.net/sikorsky_rotorcraft_demo.mp4" type="video/mp4"> Your browser does not support the video tag. </video>
Previously:
https://www.homemadetools.net/forum/...995#post210565
https://www.homemadetools.net/forum/...142#post165164
https://www.homemadetools.net/forum/...219#post149989
https://www.homemadetools.net/forum/...285#post134952
https://www.homemadetools.net/forum/...910#post133618
