Tacet Posted March 4, 2022 Report Share Posted March 4, 2022 On 03/03/2022 at 10:44, john.k said: A large size crisp packet and tube of the sticky stuff would have saved the day........three people increase displacement how much??.....was it a weight watchers outing? Three people of the stern deck and the draft increases by 115mm? Far from usual, I think Link to comment Share on other sites More sharing options...
MtB Posted March 4, 2022 Report Share Posted March 4, 2022 49 minutes ago, Tacet said: Three people of the stern deck and the draft increases by 115mm? Far from usual, I think I thought that too. Doesn't stand up to analysis at all I don't think. Also, the lines drawn on the photo show the waterline way higher than would be normal. Generally the uxter plate sits on the waterline. On the photo, the waterline is drawn about 6" higher than the uxter plate. This does not make sense. Link to comment Share on other sites More sharing options...
koukouvagia Posted March 4, 2022 Report Share Posted March 4, 2022 On 03/03/2022 at 09:15, MtB said: Point of Order... I can't see any mention in the report of it being a Springer in particular. Also, the photo in the report of the counter shows a conventional swim and uxter plate, rather than the "V" shaped base plate and weird counter design that most (if not all) Springers have. Also, looking at the photo, it appears the air intake freeboard WAS considered by the over-platers who appear to have raised it by the width of the rubbing band and inserted a blanking plate. The whole idea of cutting holes through the hull for air cooling strikes me as stupid though, as the result is highly predictable. Here's a picture I took of the boat in Greenland Dock after the sinking. It shows the extent of the overplating. Link to comment Share on other sites More sharing options...
Alan de Enfield Posted March 4, 2022 Report Share Posted March 4, 2022 41 minutes ago, koukouvagia said: Here's a picture I took of the boat in Greenland Dock after the sinking. It shows the extent of the overplating. Any idea what that huge steel 'slide' and framework is that is welded on the stern ? It looks like a sort of hybrid hull . short V-sides and flat base plate. Link to comment Share on other sites More sharing options...
Mad Harold Posted March 4, 2022 Report Share Posted March 4, 2022 1 hour ago, Alan de Enfield said: Any idea what that huge steel 'slide' and framework is that is welded on the stern ? It looks like a sort of hybrid hull . short V-sides and flat base plate. Could it be a collapsible frame for a pram cover? Link to comment Share on other sites More sharing options...
beerbeerbeerbeerbeer Posted March 4, 2022 Report Share Posted March 4, 2022 I think it was the weight of the extra anodes that did it. …I could be wrong. Link to comment Share on other sites More sharing options...
David Mack Posted March 4, 2022 Report Share Posted March 4, 2022 7 hours ago, Tacet said: Three people of the stern deck and the draft increases by 115mm? Far from usual, I think The report doesn't say that. It says after recovery it was determined that the bottom of the vent opening was 65mm above the water line. The accident happened not on a flat canal but on the Thames where even in calm weather the waves may be a few inches high. So as soon as the boat departed South Dock Marina it would have been taking in a little water from each wave crest. This would have weighed the back end of the boat down, meaning more water would be taken in from each wave crest. This must have continued for some time until the crew noticed the engine note change. By this time the engine was "half submerged", so there must have been a substantial quantity of water in the engine bay, and the back end of the boat would be a lot lower than when they set out- quite possibly already by more than the 65mm original freeboard. I can easily believe that in this situation people moving to the back of the boat could push the back end down by another 50mm, especially if they were predominantly on the same side of the boat as the vent. In any event it doesn't really matter whether the total drop of the back end was 115mm or not. The end result was more or less inevitable with that little freeboard in the presence of waves. Link to comment Share on other sites More sharing options...
David Mack Posted March 4, 2022 Report Share Posted March 4, 2022 7 hours ago, MtB said: Also, the lines drawn on the photo show the waterline way higher than would be normal. Generally the uxter plate sits on the waterline. On the photo, the waterline is drawn about 6" higher than the uxter plate. This does not make sense. Well the report notes that the boat was much deeper in the water than originally designed, due to the weight of the overplating (and presumably with no corresponding reduction in the amount of ballast carried). Link to comment Share on other sites More sharing options...
syd Posted March 4, 2022 Report Share Posted March 4, 2022 Thing on the stern there might be for a motorbike, not sure but a guess. Link to comment Share on other sites More sharing options...
koukouvagia Posted March 4, 2022 Report Share Posted March 4, 2022 4 hours ago, Mad Harold said: Could it be a collapsible frame for a pram cover? It is a frame that held a generator. I took this not very clear picture shortly after the boat sank. It had been beached just outside the entrance to Greenland Dock. 1 Link to comment Share on other sites More sharing options...
john.k Posted March 5, 2022 Report Share Posted March 5, 2022 Another question might be ...Why didnt they notice the solid stream of water from the bilge pumps before they cast off? Link to comment Share on other sites More sharing options...
Tacet Posted March 5, 2022 Report Share Posted March 5, 2022 14 hours ago, David Mack said: The report doesn't say that. It says after recovery it was determined that the bottom of the vent opening was 65mm above the water line. It also implies that the bottom of the vent was 50mm below the waterline when the three persons were on the stern deck. It increased rather as the boat sank, of course. The diagram shows the 65mm as being the distance between the uxter plate and the bottom of the vent - but that distance is, from the photos, much more. So I can't have much confidence in the details of the report. Link to comment Share on other sites More sharing options...
David Mack Posted March 5, 2022 Report Share Posted March 5, 2022 18 minutes ago, Tacet said: The diagram shows the 65mm as being the distance between the uxter plate and the bottom of the vent - but that distance is, from the photos, much more. So I can't have much confidence in the details of the report. The diagram in the PLA Safety Bulletin doesn't show any dimensions, although the text of that report stares that the bottom of the opening is approximately 65mm above the water line. The diagram in the other document posted (source unknown) clearly shows the 65mm as the distance between the "waterline in still water" and the top of the "blanking plate" i.e. the bottom of the vent opening. 21 minutes ago, Tacet said: It also implies that the bottom of the vent was 50mm below the waterline when the three persons were on the stern deck. It increased rather as the boat sank, of course. The boat was already sinking before the crew realised there was a problem and congregated on the back deck. Link to comment Share on other sites More sharing options...
Tam & Di Posted March 5, 2022 Report Share Posted March 5, 2022 and the additional weight of the generator cantilevered out beyond the original stern would not help. Tam 2 Link to comment Share on other sites More sharing options...
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