Yesterday we took two RIBs into Newtown Creek on the Isle of wight, very tidal with a small entry and strong tides when in flow. Not wishing the poor yachties any more red faces but with our clients they were amazed how someone might get this wrong. They were OK but whilst in the creek the water went down a lot more leaving a port hole almost submerged and they were inflating a small inflatable and as we left they sent out a Pan Pan. No real danger to crew as they were feet from the shore and numerous other boats close by but this was not a bilge keel yacht so could just flop onto ints side if the water completely dropped.
We saw lifeboat crew from Yarmouth two hours later and crew OK and lifeboat just helped with a kedge anchor for them from their inflatable as the lifeboat had no water below to enter.
Not the only yacht to go aground, 7 vessels got stuck outside the Beaulieu for a while.... It wasn't springs but the atmospherics forced a lower than expected level.
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A boat is not truly yours until you start fixing the things that you have personally broken.