Subsonic wind tunnel at NASA's Ames Research Center in California.
Fullsize image: https://s3-us-west-1.amazonaws.com/h...l_fullsize.jpg
https://s3-us-west-1.amazonaws.com/h...ind_tunnel.jpg
Previously:
https://www.homemadetools.net/forum/...015#post160566
https://www.homemadetools.net/forum/...162#post153717
https://www.homemadetools.net/forum/...493#post110756
https://www.homemadetools.net/forum/...874#post152596
https://www.homemadetools.net/forum/...053#post160683