The Leduc 0.21 was a French research aircraft developed in the 1950s to test ramjet propulsion.
https://diqn32j8nouaz.cloudfront.net...al_ramjet1.jpg
https://diqn32j8nouaz.cloudfront.net...tal_ramjet.jpg
Previously:
https://www.homemadetools.net/forum/...508#post158761
https://www.homemadetools.net/forum/...092#post157384
https://www.homemadetools.net/forum/...206#post149917
