Tuesday, 8 December 2015

GM FINALE AND CONCLUSION.

To enable a critical examination to be undertaken of the evidence as to the ship's behaviour on her second homeward voyage, her approximate metacentric height when leaving each of the Australian ports has been calculated. It is as follows:


leaving Sydney               about foot

leaving Melbourne           about 1.5 feet

leaving Adelaide             about 1.9 feet


The above GM figures refer to the final voyage, when Captain Ilbery was able to deal with the issue of coal in 'tween decks, and apply the principals of significant dead weight, lowest down. Not one of the figures correlates with a top heavy or tender steamer. The progression of the figures to a maximum of 1.9 ft. illustrates the cumulative dead weight cargo loaded from port to port, resulting in a very stable (GM) vessel. 

Mr McDiarmid, pilot, Port Adelaide, gave crucial testimony:

 I was pilot to the "Waratah" inwards and outwards on her last voyage. Inwards. took charge of her 2 miles to the southward of the Port Adelaide Lighthouse and berthed her at the Ocean Steamers Wharf, Port Adelaide. She had the assistance of a tug which was placed right ahead all the way to assist at the bends in the river. Her draught, as recorded by me after berthing, was 25 feet 8 inches forward and 26 feet 4 inches aft. Pilotage is paid for on tonnage and not on draught (excluding ballast). We steamed in slowly. Had no difficulty in steering the ship or otherwise.

It is interesting to note that despite an average draught of 26 ft. arriving at Adelaide, Waratah's GM was 1.5 ft.. This is marginally less than when Waratah departed Durban, but the draught differential was significant = 2.9 ft. ! How could this have been. I believe that it was a combination of pumping out ballast tanks on arrival and the presence of at least 1000 tons of lead concentrates lowest down - same lead loaded inbound at Adelaide.

She had a slight list to port when I boarded her, but it was very little. No remarks were made about it or anything else, except the business we had in hand. She was not down to her marks or anywhere near it when I boarded her. When going round the bends she had a tendency to list when the tug got a strain broad on the bows, caused by the action of the helm and tug combined. I would not expect this in a ship that was nearly loaded as this one was. It might be ascribed to several reasons, the principal one being that Port Adelaide being the last port and taking the heaviest cargo (flour, grain, &.),space would be left to take that cargo as low as possible. Another reason might be the starting of pumping out water prior to taking in that cargo, and a third reason might be that she was naturally a somewhat tender ship. I had had charge of the vessel before and remarked this later to the captain on the previous voyage. Do not remember what he said, but am under the impression that he agreed with me. What caused the remark was, when negotiating the turn in the cutting at Snapper Point coming up the river she rolled from side to side without any apparent cause. I knew of none.

This further confirms two things; ballast water was a necessary component of a GM stable Waratah and it disputes the claim made that the ballast tanks were empty for this final voyage. Mr. McDiarmid draws our attention to the fact that the heaviest cargo, low down, was loaded at Adelaide, ultimately achieving the GM figure of 1.9 ftBut how was it possible that by discharging a paltry 250 tons of cargo at Durban the GM could have fallen so significantly from 1.9 ft. to 1.5 ft. ? The answer is quite simple; there was no coal on the spar deck, prior to Durban ! 

The Court has no evidence as to the amount of water ballast in the tanks leaving Melbourne and Adelaide, and has been compelled to assume it from the draught. There is evidence that on leaving Sydney she had 651 tons of water ballast in the double bottom. This tallies with the draught given in the log. On leaving Melbourne and Adelaide 360 tons of water ballast are assumed for the reason given above. 

The Court came to the same conclusion; the Waratah did operate on her final voyage with ballast water, a vital component of GM stability. The Waratah needed 651 tons of water ballast leaving Sydney, but only 360 tons, leaving Melbourne and Adelaide. Cumulative loading of cargo reduced the need for more than 360 tons of ballast water. Proportionately the largest portion of heavy cargo was loaded at Adelaide, raising the GM to 1.9 ft. It is interesting to note that ballast tank 1 did contain 129 tons of water (see previous post). If one adds ballast tank 8 (222 tons), we get a figure of 351 tons (almost 360 tons), and if you recall, the builders advised the filling of ballast tank 8 to assist with GM stability.

In connection with the stability of the ship on this voyage, Mr. Wade's evidence may be mentioned to the effect that the captain told him that he (the captain) had learned the peculiarities of the ship, and now knew how to stow her. 

He sure did. 

It is not easy to reconcile metacentric heights such as those set out above with the positive testimony of some of the witnesses, as for example the tenderness on entering Adelaide spoken to by the witness McDiarmid. His deposition shows signs of careful observation. In the matter of the draught, for instance, his evidence is in accord with the log book, whereas the witness Johnson, whose evidence would otherwise discount McDiarmid's, is largely in error on this point. McDiarmid, however, adds that she showed no signs of tenderness when leaving Adelaide. 

There is a fair amount of evidence to show that the ship was upright when leaving each of the Australian ports. 

It could not have been anything else - the Waratah was upright, and not tender.



Returning to Mr. McDiarmid:

I boarded the vessel again as pilot to take her out of the port down to the outer harbour on the afternoon of 6th July, 1909. Had the tug "Wato" in attendance to help us off the wharf down the river and alongside the Outer Harbour Wharf. I turned the vessel on her inward trip so that she was heading down stream ready for departure. When starting the tug plucked her off from the bows to get away from the wharf and then went ahead. The ship was heavy in working and slow to answer the helm, but she had no sign of tenderness, neither did she on the way down the river or in going alongside the Outer Harbour Wharf. The heaviness mentioned I attributed to her heavy draught going down the Port Adelaide River, which was 27 feet 9 inches on an even keel. I put her as close as I could to the wharf and the tug then left the bow and went amidships on the starboard side and pushed her into the wharf. I left the vessel when she was made fast to the wharf. The next afternoon I returned to take her to sea. She was then drawing 28 feet 3 inches forward and 29 feet 5 inches aft. The same tug was again in attendance and plucked her off the wharf at the stern, the ship heaving off to her cable to get her bow off. She was not then down to her marks. She was quite upright and stiff, and proceeded to sea as far as the Semaphore Anchorage without any difficulty or any sign that the ship was tender or that anything was wanting to make her a seaworthy vessel fit for the voyage. I knew the master and officers only when on board the ship, and have not heard from anybody on board since I left her. I always looked upon her as a tender ship, but not to such an extent as to make her unseaworthy. Apart from my remarks to the captain about the ship rolling I never referred to the matter again, either to him or to the officers, and they never made any remarks to me as to that or the vessel's behaviour at sea. The circumstances being peculiar, i.e., the rolling, I mentioned it to some of the other pilots at the time, and they thought as I did. 

Mr. McDiarmid made the case of the Waratah unambiguously clear. He remarked that the Waratah had a tendency to tenderness, which was true. However, this tendency could be manipulated, transforming the Waratah into a steamer which was not tender. Mr. McDiarmid said; 'The ship (Waratah) was heavy in working and slow to answer the helm - no sign of tenderness'. This statement captures the essence of the Waratah's stability quandary. In order to reduce and extinguish tenderness, she had to be heavy. Mr. McDiarmid made a further sensational statement, 'The heaviness mentioned, I attributed to her heavy draught going down the Port Adelaide River, which was 27 ft. 9 in. on an even keel'. The man referred to the Waratah having a heavy draught of 27 ft. 9 in., which seems ludicrous in the context of a max. draught of more than 30 ft. This draught figure, however, was in excess of 26.9 ft. which should have been the true draught for the Waratah. Mr. McDiarmid had just confirmed that the load line of the Waratah was underestimated. By the time Mr. McDiarmid returned to take the Waratah out from the outer harbour, she had been loaded to her maximum, creating a draught of 28 ft. 3 in. (same as Durban) forward and a whopping 29 ft. 5 in. aft. Mr. McDiarmid described the Waratah as 'quite stiff and upright'. And so she ought to have been !!




Conclusion:

Waratah was a problematic steamer from the time she was conceived until launch. The owners wanted a steamer with three superstructure decks sitting astride a hull based on the preceding Geelong, but marginally larger. The owners wanted and got a greater net tonnage for the hull dimensions, relative to that of the Geelong, allowing for functional overloading. But more than this, Waratah was to be classified according to Lloyd's (1907/1908) 100 A1 spar-deck class with freeboard, when in point of fact her 'scantlings were practically the same as those for the three-deck class'. 

This opened a can of worms in terms of her certified freeboard, which was too low for a vessel of this size, and had implications for her certified maximum draught, which should not have been 30 ft plus, but similar to the draught of the Geelong - 26.9 ft. - virtually, a hull identikit. What's more and highly disturbing is the fact that dimensions of scantlings, plates, steel decks, tie plates, stringer plates, hull thickness, rivet strength etc.. were inadequate, equating with the smaller vessel classification. It is no wonder that the budget price of 139 900 came in well below that for equivalent sized passenger / cargo steamers of the time, even taking into consideration extras bringing the total price to 155 000 pounds. In light of diminished overall structural strength, it is not surprising that bolt heads came loose, gaps appeared in the decks, and a steel ladder snapped. 

Waratah was 'naturally' top heavy and this persisted throughout her first three major voyages. Captain Ilbery was confronted with a problematic steamer but being a loyal employee, had no choice but to make the best of a bad situation. Together with input from the builders, it was finally decided that GM stability could only be achieved with significant dead weight, lowest down, including the filling of ballast tanks 1 and 8 and absence of coal within the 'tween deck reserve bunkers and spar deck at 42 cubic feet to the ton, which was a significant, GM reducing factor. 

The price to be paid for shifting the centre of gravity downwards to achieve a GM of 1.5 ft., was technical overloading, which reduced free air, buoyancy, and placed too much strain on the Waratah's hull and structure. We shall probably never learn the full truth about what and how much cargo was on board when she departed Durban, but there were certainly enough period newspaper reports alluding to dead weight cargo approximating 9 000 tons and more. With the appalling record-keeping regarding details of cargo on board, there might very well have been gold and silver as well. But the tragedy became the mystery, and for those who are inclined to believe the Harlow account, Waratah went down like a stone due in part to the factors outlined above.










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