Comments by "Antony Wooster" (@antonywooster6783) on "Video-Two British warships collide in Persian Gulf. Smart ships for dumb people. Unsurprising..." video.

5:25 Yes, I know. It IS fibreglass, there are magnetic mines which are set off by the ship's disturbance of the magnetic field when it passes over the mine and also mines which are magnetic and are attracted to ships. So a "mine-sweeper" or "mine-hunter" needs to make as little magnetic disturbance as possible. This means it cannot be made of steel. So what better than to make it out of fibreglass reinforced with plastic resin? You could, I suppose, make it out of copper or stainless steel (Some types are non-magnetic) but both would be heavier and dearer.
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