Ran across 1 June 1940 in Grid AM something lol just west of the Northern tip of Ireland chunked 3 eels at her at different depths and all 3 bounced off. Looks like 1-2 meters on impact should work.
Anything around 2-4 metres should be fine
__________________
Wise men speak because they have something to say; Fools because they have to say something. Oh my God, not again!!