Talk:3013: Kedging Cannon

First? PRR (talk) 02:05, 19 November 2024 (UTC)

Good essay on real-life (or this-world) kedging-- http://www.sailmagazine.com/cruising/cruising-tips/the-lost-art-of-kedging-how-to-set-a-kedge-anchor/ PRR (talk) 02:07, 19 November 2024 (UTC)

Nice. I think I managed to somehow get in first (before I logged in); first time I've done so, so apologies for not knowing all the conventions. I think the title text is the main non-obvious thing, since the simile between a windmill's mechanical function and that of tacking seems clearly intentional,but I'm sure that could be edited to be clearer than my hasty writup. Mneme (talk) 02:10, 19 November 2024 (UTC)

For a brief, brief, moment, my brain failed to swap in and dredge up the memory of what kedging was, and I wondered if they were trying to use the aft cannon as a weak propulsion mechanism (hey, if it was a spacecraft…). And then I remembered what kedigng was and—DUH! JohnHawkinson (talk) 02:29, 19 November 2024 (UTC)

If it wasn't for kedging, I probably wouldn't be able to make it all the way through November. 108.162.245.133 04:25, 19 November 2024 (UTC)

Ha ha now exactly what you mean. The three longest month of the year are November November November... :-) --Kynde (talk) 10:05, 19 November 2024 (UTC)

Having a certain number of winches helps. 172.68.23.92 10:44, 19 November 2024 (UTC)

Wow, whoever wrote the Speed and Economic Analysis section, you are amazing! 172.71.98.135 05:13, 19 November 2024 (UTC)

Sadly is was done by an anonymous IP address... But cool analysis. Have no idea what he actually calculates or if it is correct though ;-) --Kynde (talk) 10:05, 19 November 2024 (UTC)

The system described doesn't need two cannons, just two anchors and winches for continuous operation. As something of an anonymous IP address editor myself, I am checking the math and intend to parameterize the assumptions for different size boats, different headwinds, and other different parameters. If I am successful, I will log in to upload a graph showing when cannon kedging is superior (if it ever is....) 172.68.23.92 10:44, 19 November 2024 (UTC)

I've got a strong hunch that this comic is about a captain who fails to take into account recoil / conservation of momentum, which is a frequent mistake. The cannon propels the anchor with great force, but, as it is connected to the ship, the ship is pushed back with the same force (minus some heat losses) before the anchor can settle. Therefore, in this setup the ship will only move forward at all if the anchor ends up at a greater horizontal distance from the ship's original position than the distance between the ship's original and post-cannonshot positions. The third panel, where the ship is drawn further to the left, indicates that the setback is significant and the ship only moves back and forth in the same place. Like, it literally takes forever. The title text is key: Only if the captain manages to use a source of power that is independent from the vessel's movement (for example: wind from the wrong direction) this cannon will have any propagating effect. For manual kedging, the proportion between the length of the anchor chain and the setback of the ship is somewhat different, and the muscles of the sailors do most of the work of dealing with recoil. Or am I missing something? Transgalactic (talk) 11:07, 19 November 2024 (UTC)