Monday, 2 December 2013

Waratah - impressions of top heaviness and instability.

Confusion was created by the witness accounts of crew on the vessels Harlow, Clan MacIntyre and Guelph. But my thoughts now return to the question of the Waratah's stability. If one glances over images of steamships from the era, including the Waratah's sister ship Geelong, there is not much about the profile of the Waratah which stands out as glaringly unusual. The additional superstructure boat deck on the Waratah did however create a (relative) visual impression of top heaviness.

By 1908 shipbuilders were adding extra third superstructure decks and power delivered by more sophisticated quadruple expansion steam engines. Steamships were moving with progress, becoming bigger and more powerful. It was not just enough to carry emigrants and cargo. The luxury component of travel was increasingly desirable. The Blue Anchor Line and the Waratah were no exception to progress. An larger number of luxury staterooms and saloons over and above cargo and emigrants had to be accommodated, forcing the necessity for additional decks.

An additional deck could theoretically contribute to top heavy instability if inadequate attention was paid to compensation, balanced substantial weight lower down within the hull of the vessel. Luxury also equated with comfort and these designs needed to find the balance between safety and comfort. Relative top heaviness provided a more comfortable rolling pattern. A larger number of witness accounts were in favour of the Waratah's comfort and performance.  In addition to this, most of the expert witnesses gave opinions in favour of the stability of the Waratah.

When the Waratah left port at Durban on the evening of the 26 July 1909, witnesses including the port pilot were adamant that she was stable, upright and in fine condition. The Waratah was also fully loaded ensuring adequate weight and ballasting lower down in the ship which offset relative top heaviness. The Waratah had a similar triple deck profile to a number of successful ocean going steamships in 1909, and when she left her final port of call she gave no cause for concern or speculation as to her seaworthiness. The Waratah was a fine sea going vessel and the pride of her master, Captain Ilbery. As she steamed past the bluff out to sea, no one including Captain Ilbery was likely to have been aware of latent problems, potential for fire and the sequence of events that would ultimately claim the 500 ft steamer off the Wild Coast.

SS Waratah

SS Koombana (1908)

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