Monday, 25 April 2016

SAWYER'S VISION AND THE FORWARD WELL.

The forward well was 73 feet in length, and had at its forward end a refrigerator house 28 feet long and 34 feet wide; the after well was 30 feet long. Both wells had bulwarks 4 feet 2 inches in height above the plated deck, with three wash ports on each side in the forward well, and two on each side in the after well. The size of each washport was 3 feet 6 inches by 18 inches. The hatch in the forward well measured 30 feet 4 inches by 19 feet 6 inches, and that in the after well 19 feet 6 inches by 26 feet. Both were fitted with hatch covers of 3-inch pine supported by transverse beams formed of 1-inch plate and four angles. The hatch coamings were 3 feet high. 

Claude Sawyer had a final vision of Waratah labouring in heavy seas, taking a large volume of water over her bow, and before being able to recover, another deluge, some 500 tons of water trapped in the forward well. She then rolled over to starboard and went down like a stone.

Given all we know about Waratah this vision was both haunting and highly plausible. The forward well was 73 ft. x 59 ft. =  4307 sq ft.. Bulwarks were 4 ft. 2 in. from the deck, which gives us 
17 228 cubic feet. equivalent to 480 tons of water. Sawyer was not far off quoting 500 tons of water. The forward hatch was 30 ft. 4 in. x 19 ft. 6 in., 589.87 sq ft.. The coamings were 3 ft. high, which gives us a total volume of 1769.625 cubic ft.. This would be equivalent to 49 tons of water. The maximum shear strength of pine (long leaf) is 1510 psi, which translates into a maximum weight of 120 tons for the hatch. 49 tons alone should not be a problem, and 65 tons (up to bulwarks), would not be a problem either - theoretically. However, 480 tons of water suddenly collected in the forward well would have a significantly destabilising effect on Waratah, particularly if the flow of force was to one side, port or starboard, and overwhelmed drainage.

It is interesting to note that a significant force would be required to overwhelm the 3 in. pine covers. A maximum volume of water in the forward well would not be enough to breach the hatch.



  

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