Monday, 7 December 2015

SPAR DECK COAL.

4. The incompleteness of the evidence as to the coaling at Durban. The foreman who had the actual stowage of the spar-deck bunker is reported to be dead, and the only evidence as to the amount placed there is that of Mr. Victor Lindsey Nicoll, manager to the firm which supplied the coal. He deponed that he put "not less than 250 tons" there. He was unable to say how much more there might have been, but added that the space was "possibly one-third" full. From the deposition of Mr. William Robert Wright, manager for Messrs. William Cotts & Co., shipping agents, it appears the captain instructed Messrs. Nicoll & Co., in his presence, to place "about 250 tons on the spar-deck." In the calculations it has been assumed that 250 tons only were there. It was suggested in the course of the Inquiry, but without any evidence to support the suggestion, that the chief engineer might have over-estimated the amount of coal used on the voyage, and that he really had on arrival at Durban a considerable amount over that shown in his abstracts, this helping to account for the difference between her displacement and the known weights. If, instead of assuming No. 1 tank (129 tons) as filled, it is taken that he had a surplus of 129 tons of coal, which it is not unfair to presume must, in that case, have been in the spar-deck bunker, a reduction of about .3 feet in the metacentric height would ensue. Another point to be considered is the trimming of the coal at Durban. If the statement that only 250 tons were placed in the spar-deck bunker is accurate, the coal placed below must have been properly trimmed, but if the latter were not properly trimmed, there must have been more than 250 tons in the spar-deck space. It is to be remarked that on this voyage the "Waratah" coaled in much less time than on her maiden voyage, but, according to those who stowed the coal, it was not done at an unusual rate. 

It is very important to note that Captain Ilbery specifically requested that 250 tons of coal be stowed in the spar deck bunkers. This confirms my contention that Captain Ilbery purposefully placed coal in the spar deck bunkers to reduce the GM of 1.9 and corresponding righting force which I believe was responsible for the 'jerk' experienced on the voyage from Adelaide. This was not a careless oversight relating to 'quick' loading. It is interesting that 240 tons of cargo were discharged at Durban, almost the same weight as the coal on the spar deck. Captain Ilbery wanted to maintain an overall draught of 28.9 ft. for steadiness, but with a reduced GM for passenger comfort and safety.

It is also interesting to note that the chief engineer might have over estimated coal consumption on the crossing from Adelaide, which in turn might explain the alleged additional 15 tons of coal consumed per day. 

250 tons of coal on the spar deck reduced GM by a factor of 0.3 ft. which in effect would have reduced the GM from 1.9 ft. to 1.6 ft.




loading coal, 1908. Note the list of the steamer.



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