[FPSchazly]

Originally Posted by Aktungbby

No! No! that's (ring) to keep mile-long seine/gill fishing nets from tangling the propeller.... often sinking the fishing boat. http://www.prop1.org/2000/accident/1989/890712a1.htm & http://www.dailymail.co.uk/news/article-3687891/Portuguese-submarine-caught-net-French-fishing-boat-English-coast.html http://news.nationalpost.com/news/world/fishing-boat-captain-says-a-russian-submarine-lurking-in-u-k-waters-snagged-his-net-and-nearly-dragged-him-under Seriously; it's a big problem for all submarine vs net fishing boats-there have been fatalities for years Look up "fishing boats snagged by submarines". It's really bad!

Ah yes, that makes a lot of sense. At one point in time, I had considered it was to keep the towed from getting snagged in the propeller, as well.