The sound has gone from my computer so I couldn't make any sense of the link. However, we had a 72' Les Allen as our final canal narrowboat (actually built by his sons). From canals and river motor-boating I gathered that the squatting problem is down to cavitation. If forward movement is hindered energy goes to sucking in air. The mixture with water is less dense than water itself and offers less support to the hull. The stern squats and will squat still deeper if the helmsman revs up. The stern gear may be damaged. Changing to neutral usually lets the hull float free, when it can be pushed into deeper water.
Cavitation is the reason that narrowboats have broad sterns. Butties were hauled and had no engine but pointed sterns. When converted to boats, you will probably have seen the huge wings that were added to prevent the air from being sucked round the prop.
I guess Poppy had a weed hatch to give access to the prop. Less than an hour from the Allens' yard on our maiden voyage we collected a huge tarpaulin and spent a good two hours sawing it free via the hatch with a bread knife (a vital piece of equipment, not mentioned in the literature).
We once came across a hire boat sitting in the middle of the cut. The crew had cleared their prop but left the weed hatch open before cruising off. I don't know how it was freed but my photograph of it was published in a canal magazine.
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Ever Given new
Ever Given new
