We just got back from a great trip and only had one mishap.
While entering the Fox Isle Thorofare in Penobscot Bay, with a nasty current of over a knot and a half and only about 1 knot of wind, we picked up some floating poly line on the prop. No, we did not hit a lobster pot this was black floating line that the lobstermen use between traps on the bottom. They are not supposed to be using it anymore but they do.
On moon tides the line gets washed back off the shore and into the bay to float, mostly invisibly, until some unsuspecting boater sucks it into his or her prop as we did.
At first it was just a nasty vibration and I thought it could be a large piece of kelp so I tried a quick burst of reverse. Wrong! It stopped the motor dead. So now we're dead in the water and the current is moving us towards the ledges faster than our sails can fight it. I mustered all my light air racing skills managed to claw off the ledges and sail into the thorofare where I set the hook and dove on the mess..
I tried to pull as much of it out of the water as I could but with the current and the amount on there some escaped. In total it took almost 40 dives on the prop to cut this stuff free and my knife is very sharp. The ball of line was as big around as my prop and had begun to melt on teh shaft already.
Why didn't I wear a wet suit? Well our daughter was hungry and I thought this would only take a few seconds to cut free. Never second guess the cold Atlantic ocean or you'll come out of the water as I did with major shrinkage! All I could say to my wife was "I was in the pool" a George Castanza quote from Seinfeld!!
Other than picking up some floating like the trip was perfectly smooth with no failures, mishaps or broken equipment.
This is a piece that was against the shaft! So yes polypropylene line can melt even when fully submerged!
Cary a sharp knife with a wrist lanyard, mask, flippers, wet suit and a 5mm dive hood (prevents your head from banging the bottom of the hull) when cruising Maine and DO put on your wet suit!