Thursday, 3 November 2016

PIG IRON AND LEAD CONCENTRATES.

INITIAL REACTION AND COMPARISON WITH SS WARATAH.

The Argus, Melbourne, Friday 31 March, 1911.

CAPSIZE IMPROBABLE.
BRISBANE, Thursday - In view of the
widespread statements that the Yongala
"turned turtle," Mr. Wareham flatly 
contradicted the possibility, and pointed 
out that the steamer had been running 
on the coast in the interstate trade for 
eight years - five years running between 
Sydney and Fremantle. Consequently she 
crossed the Australian Bight every four weeks, 
often with less than 100 tons of cargo and not 
more than 200 or 300 tons of coal. She never 
gave owners, master, crew, or passengers any
cause for uneasiness on account of her 
behaviour. It was unreasonable to suppose
that the Yongala, which left Brisbane with
2,000 tons weight in her bottom and only 5
tons of cargo on deck, could turn turtle.


This initial reaction from a representative of the owners is interesting. The scene was set for the Inquiry to come; under no circumstances was Yongala to be presented as a tender steamer which could have turned turtle in a cyclone. But the rumours were there as soon as one week after the disaster. Yongala did indeed have a good track record, particularly across the Bight. However, Mr. Wareham failed to mention that she carried 164 tons of pig iron ballast to compensate for minimal cargo and coal during these runs. The distance between Fremantle and Adelaide is 1720 n miles. Yongala consumed, on average, 60 tons of coal per day. Cruising at a modest 12 knots she would have taken 6 days = 360 tons of coal. Mr. Wareham already as early as 31 March, was prone to exaggeration in favour of dispelling the rumours and exaggerating Yongala's capabilities. He protested far too much! It is known from the Inquiry that Yongala departed Brisbane with 11 tons on deck. Again, Mr. Wareham attempted to underplay the top heavy component by reducing this figure to 5 tons. It is interesting to note that Yongala had a jerky recovery when steaming in ballast with the 164 tons of pig iron (forward). The pig iron lowered the centre of gravity, raising GM, and with it the righting force recovering from a list. This jerky recovery was not as pronounced when Yongala carried cargo, including cargo on deck. The deck cargo would have reduced the GM and done away with the jerky recovery. This reminds me of the Waratah. Captain Ilbery, finally on the last voyage, had sorted out Waratah's inherently tender condition by adding 1300 tons of lead concentrates in a lower hold at 11 cubic feet to the ton, 8 ft. high. This produced a stable steamer with a GM of 1.9 ft., which was pretty good in those days. However, the increased righting forced, as in the case of Yongala, produced a jerky recovery which had passengers falling on the promenade deck during the voyage from Adelaide to Durban. Many observers believe that by stowing 300 tons of coal on Waratah's spar deck at Durban made her dangerously top heavy for her fatal leg of the run to Cape Town. What Captain Ilbery was in effect doing, similar to deck cargo on Yongala, was to reduce the GM to a more palatable 1.5 ft. and the reduced righting force cured the jerky recovery = no more potential passenger falls. Captain Ilbery was not a fool, nor was he reckless by subjecting a steamer with a reputation for tenderness to further 'destabilising' coal on the spar deck. It was done for good reason. Returning to Yongala, I believe that the absence of the pig iron had a significant impact on tenderness and being 36% full in terms of cargo dead weight, most of which was stowed in the 'tween deck, made Yongala tender and vulnerable to turning turtle in a gale. You could not win with these inherently top heavy steamers.

There is no smoke without fire!


SS Yongala


SS Waratah, loading at Port Adelaide.

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