3119: Flettner Rotor

2025-07-25T19:25:12Z

2600:1011:B34C:463E:7C3F:EC6F:6F88:4B4D: Undo revision 381905 by Aktyagi123 (talk)

{{comic
| number = 3119
| date = July 23, 2025
| title = Flettner Rotor
| image = flettner_rotor_2x.png
| imagesize = 385x359px
| noexpand = true
| titletext = "And in maritime news, the Coast Guard is on the scene today after an apparent collision between two lighthouses."
}}

==Explanation==
{{incomplete|This page was created by a spinning shaft. Don't remove this notice too soon.}}

This is another one of [[:Category:Tips|Randall’s tips]]. [[Randall]] is pointing out that a {{w|Flettner rotor}} can make a boat look like a lighthouse, and thus make other boats avoid it.

A vertical-axis Flettner rotor is a smooth cylinder which is spun along its axis. As air passes across it from the side, an aerodynamic force is generated at a right angle (i.e., forward) to propel the boat in the desired direction.

As a tall vertical cylinder, the rotor has the approximate appearance of the column of a stereotypical lighthouse. If a directional light were attached at the top, it too would spin, sending out periodic flashes of light and making it even more similar to a lighthouse. Or, as it appears to be in the comic, a fully working {{w|Lighthouse#Components|lantern house}} could be fixed to the top of the non-rotating core to the rotor, making it look even more like a lighthouse (and also allowing independent control of the light's flash rate).

To people on a vessel directly in the path of the disguised boat, it would appear that they are sailing or drifting towards a hazard, prompting them to take action to navigate away from it, thereby clearing its course. In fact, there would be no need to have a Flettner rotor at all to achieve this effect — a simple, non-rotating column with a rotating or flashing light would do just the same thing for a boat that is powered by other means, and seems a small additional effort if you're already taking the trouble to install the fake rocks and light.

The title text describes "an apparent collision between two lighthouses", which could refer to two Flettnerized boats colliding with each other because they were ''both'' assuming that everyone else will give them the right of way. Alternatively, a single Flettnerized boat could complacently collide with an actual lighthouse, having similarly dismissed it as another boat that should have taken avoidance measures. This alludes to an old {{w|Lighthouse and naval vessel urban legend|urban legend}} in which a naval vessel insists that another radio operator at sea divert course to avoid a collision, demanding right of way by citing their military rank, only to be embarrassed when the other operator reveals they are not another sea vessel, but a lighthouse.

==Transcript==
:[A panel showing Cueball standing on a Flettner Rotor Sailboat, which is decorated with rocks and a lighthouse-top on the Flettner Rotor.]
:[Text beneath panel:]
:Sailing tip: If you have a Flettner Rotor Sailboat, you can add some fake plastic rocks and a light to make other boats give you the right of way.

{{comic discussion}}<noinclude>
[[Category:Tips]]
[[Category:Comics featuring Cueball]]

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3119: Flettner Rotor