So, apparently it's customary to check that your weed hatch is firmly attached before setting off on your journey. We don't normally check ours on The Green Man primarily because you need a jack hammer to release it. It's not coming loose in a hurry.
Imagine Rob's surprise to notice, after wondering why the bilge pump had gone into overdrive on The Gabble Ratchet's maiden voyage, that the engine was sitting in a vast amounts of water and that it was coming in quicker than it was being pumped out. He didn't know the weed hatch wasn't secured at this point. All he knew was that he was in the middle of the Thames with his parents on a boat that was in the process of sinking. The engine still worked, miraculously, and so he planned to head for the shallows to make salvage attempts easier.
It was at this point that he noticed the weed hatch and tightened its fastenings. No more water came in, but the engine bay was bursting with water. Cue an emergency phone call to me with the opening sentence of "fancy a rescue mission? I need pans."
Cue my emergency phone call to my mum with the opening sentence of "sinking... Pans..." Okay, not a well constructed sentence, but it did the job.
My mum arrived with pans and we went in search of the stricken crew (I'm not entirely sure how stricken they were since the boat was moving under its own power and there was a supply of alcohol onboard for the crew if needed).