Rationale
Sinking redundant warships is an effective way of testing new weapons and warships in as realistic a manner as possible. Whilst practice torpedoes are fired fairly frequently, they behave differently from warshots. Apart from other things, the practice torpedoes are designed to turn away from the target so they can be recovered, rather than hit it. In the wake of the Brent Spar incident (when Greenpeace protested over the sinking of a PB platform in the North Sea), it seemed that environmental concerns would prevent future sinkings. However the sinking of Leander class frigate HMS Sirius in 1998, appears to suggest otherwise.
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