Contra-rotating propellers - GIF
Contra-rotating propellers of an Antonov An-70. The An-70 is powered by four Progress D-27 three-shaft propfan engines, each capable of producing 10,350kW of output power.
<video controls autoplay loop>
<source src="https://s3-us-west-1.amazonaws.com/hmt-forum/contrarotating_propellers.mp4" type="video/mp4">
Your browser does not support the video tag.
</video>
Previously:
https://www.homemadetools.net/forum/...490#post122729
https://www.homemadetools.net/forum/...637#post102089
https://www.homemadetools.net/forum/...340#post113308