Tuesday, 19 April 2016

ADEQUATE BEAM AND DEPTH.

The Register (Adelaide) Saturday 17 December, 1910.

The inclining experiments of the Waratah 
when launched were satisfactory.
Speaking in regard to the width and
depth of the steamer Mr. Barry said she
was superior to most vessels. The surface 
presented to the wind by the upper
decks was of no consideration. As a
matter of fact, if they were properly water
tight they afforded extra buoyancy. The
reduction in weight through the consumption 
of coal would not affect her stability.
Trimming down would be the means 
of preserving the equilibrium.

Captain Ilbery was called away at the last minute before the inclining experiments could get underway. This is extraordinary. He was to be master of Waratah and such heeling tests were vital to his knowledge of the vessel at sea. I can only think that he knew the outcome and did not wish to participate in tests which would demonstrate Waratah's significant limitations. He had been involved with the Waratah project from design through to completion and might have felt a sense of responsibility for the end product. Perhaps, in conclusion, he was just too embarrassed to be present. Mr. Barry on the other hand praised the outcome of the tests. I think one can take this with a pinch of salt.

Waratah's depth and beam were marginally greater than that for the smaller twin deck Geelong:

                                      Waratah                                              Geelong

Beam                              59.45 ft. (initial plans, 56 ft.)                54.5 ft.
Depth                              38.5 ft.                                                 38.5 ft.
Length                             465 ft.                                                  450.25 ft.

Contrary to Mr. Barry's opinion, the above figures illustrate a marginal increase in size, which was expected to support a significant third, boat, deck - and let's not forget that the height of the superstructure decks was one full foot greater than similar steamers of the era.

Ironically  beam closer to that of Geelong's and in fact represented in plans before alterations were made, would have enhanced GM stability in that narrow deep hulls are more GM stable.

There is no doubt that if soundly built the superstructure afforded a measure of additional buoyancy but my thoughts return to statements made that boltheads broke off and the deck separated from the ironwork - hardly a recipe for 'water tight'.

Many of the eye witnesses reported that the Waratah had a tendency to list to leeward - prevailing wind, with marginal recovery. These statements contradicted Mr. Barry's confident statement that the upper decks were not affected by wind in any way.

An inherently top heavy vessel would be affected to some degree by the consumption of coal and reduction of dead weight in the lower, permanent coal bunkers.

Yes, trimming down would keep the steamer relatively stable, but my overall opinion of Mr. Barry's statement, is one of 

'me thinks he doth protest too much.'


       


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