I would like to have info on the capsizing risk of trawler fishing
vessels. We have a 150 m strong floating dyneema line (dia 100 mm)
attached to the sea bottom 43 m depth, with buoys (skippy balls) at
its free end. The line is located in a forbidden zone in the North Sea
(radius 500 m) but trawlers may disregard this. Is there any credible
scenario that a trawler will
capsize (assuming it disables its safety equipment on the trawler
booms)? Are there any instances where something like this happened?
What is the probability of capsizing, given a hook-on on the line. I
could imagine the probability depends on where the line is hooked.

Please provide verifiable references

In 1991/2, I was crew on a 30ft. snapper boat in Carnarvon Western
Australia. Also operating in the area were a fleet of scallop
trawlers. One of them, with a red hull, had a crew of four,skipper,
two men and a girl, the ships cook. The girl and one of the men were
inexperienced. It seems like they had been trawling on autopilot and
had hooked onto something. The area bottom was generally flat, and
separate from the rough areas fished by the snapper boats. The trawler
capsized, and all the crew lost their lives. Only the body of the girl
was recovered as she was asleep in the bow. The area is rife with
sharks and a person would not last long. The inquiry found that the
owners had repositioned a heavy compressor on an upper deck to where
it should have been, thus upsetting the boats stability. It is likely
that due to lack of care they had trawled into a snapper area and the
ground tackle had hooked the reef. But it was the shifting of the
compressor that was finally blamed. After the hull was found, in
fairly shallow water, and refloated, it was towed into Carnarvon
harbour and drydocked on the railway line slipway. It is probably back
operating.

the compressor should NOT have been on the upper deck..apologies