A number of searches for Koombana have been conducted, none successful, but in that process certain search sites have been eliminated in theory, given limitations of various survey methods, narrowing down the potential search area(s) which can be efficiently surveyed deploying airborne magnetometers attached to a fixed wing aircraft.
The Western Australian Museum recently commissioned a social and economic benefit assessment in terms of tourism and other community benefits should the wreck be discovered, particularly if she lies in diveable waters. The report shows that if Koombana is found, dive tourism and the potential for further interpretation of Koombana in Port Hedland would have valuable community benefits. Based on these findings, the WA Museum is in the process of seeking further and in-kind support from the public and private sectors to conduct a wide aerial magnetometer search.
I have copied the first three pages (below) of the impressive 'SS Koombana Community Benefits Assessment' and for those with an interest in the full document (30 pages) I would suggest contacting the Western Australian Museum directly.
Koombana most likely went down somewhere NE Bedout Island within an area defined by Captain Upjohn of the search steamer Bullarra. We have his quoted estimate of 27 to 28 n miles NE Bedout, but many similar historical cases of ship masters accurately defining a precise location at sea have been proven to be way off the mark - many with deviations in excess of 10 n miles; reliance on fallible dead reckoning tools of the era.
A good example is the final SOS call and coordinates coming from Titanic, the wreck of which lies a full 13 miles to the east of this position.
In this post I take a look at the area of interest and try to narrow it down further by introducing the 'fishing factor'. It is widely known that fishermen are the ones who usually stumble upon wrecks (fouled lines and nets) and know where these wrecks lie. We also know the degree of damage caused, including anchors.
Why has this not been the case with Koombana?
That Koombana could be somewhere to the north of the steamer track does not make sense in the context of the extent of commercial fishing, in particular trap fishing which would likely have stumbled upon the wreck during harvesting over many years. The graphic below illustrates a demarkation zone 'below which' fish trapping may not be conducted and which, in my opinion, narrows down the search block significantly.
In addition to this factor I have looked at a steamer track potentially further south of that assumed.
https://koombanarevisited.blogspot.com/2024/05/reviewing-steamer-track.html
Captain Allen might have drifted off course even further to the south of the plotted track, which should be factored into the area of search. It is conceivable that 130 miles NE of the centre of the cyclone the wind (gale) could have been coming from the NW or even north according to image below.
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| Note wind direction NE quadrant of the cyclone. courtesy: Australian Institute of Marine Science |
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| https://www.dcceew.gov.au/sites/default/files/env/pages/6409c07b-b972-4a58-bb3f-56196caf99e4/files/appendix-1.pdf |
https://www.dcceew.gov.au/sites/default/files/documents/wa-pilbara-trap-managed-fishery-background-information-2023.pdf
"Fishers in the PTMF use baited traps to target a variety of demersal scalefish species. Fish traps used in the PTMF are rectangular with rounded corners, with dimensions of 1600 × 1600 × 700 mm and a single opening of approximately 150 × 700 mm at the front of the trap (Figure 4-3). Trapped fish are collected by opening a gate at the rear of the trap. Traps are made of 50 × 70 mm galvanised steel mesh. Traps are set individually, each with a single rope and surface float. Traps are retrieved using a winch. Trap fishing occurs in depths of 30 to ~200 m. During fishing trips, anchors are generally only deployed while vessels are resting overnight. Vessels do not anchor while setting and retrieving traps. There is no restriction on the number of traps carried per vessel; however, each licensee is allocated an annual effort quota in 'trap days', i.e. (number of traps) x (number of days fished per trap). Hence, as the number of trap deployments increases, the number of allowable fishing days declines. Trap vessels generally operate with 2-5 fishers on board and set 60-120 traps per day (this is the total number times a trap is set each day, i.e., 20 traps each set 3 times per day equates to 60 trap sets per day), each with a soak time of about 0.5 – 2.5 hours. Trip duration is generally 5-9 days, after which the catch is typically transferred onto trucks for transport to Perth. PTMF fishers are permitted to leave traps on the fishing grounds when they return to port, but they must be unbaited and have doors secured in an open position."
Generally there is very little 'fishing vessel' activity in the zone of interest, observed as stated over an extended period of time courtesy vesselfinder.
"Charter fishing and recreational fishing are allowed in the marine park, though most people tend to stay a little closer to shore."
https://parksaustralia.gov.au/marine/parks/north-west/eighty-mile-beach/
This broader marine park zone, during many past decades, attracted spear fishermen and pearlers who would surely have stumbled upon Koombana. It seems virtually impossible not to have found the wreck, should she lie there.
Let us pause to take a closer look at the details of the pearling industry in the Pilbara.
Broome:
"By 1910 there were nearly 400 pearl lugger boats and 3,500 people in the industry supplying up to 75% of the world output of MOP. Production reached 2000 tonnes (approx. 2 million individuals) of pearl oyster collected per year (Malone et al., 1988)."
"Pearl oyster fishing grounds are located from the Lacepede Channel, north of Broome down to Exmouth Gulf in the south."
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| courtesy Wikipedia note the broad inshore band of pearling. |
"Pearl oyster patches in very deep water (>30m) are not fished at all as the safety factor does not allow an economical dive time limit." Present day.
Period (circa 1912) anecdotes:
"The Diver was working in about 19 fathoms of water remaining down 1 hour ." 35 m.
"The powers of the natives in diving, especially the females, are spoken of as something wonderful, they go down to a depth of seven fathoms [c.13m] and remain below a time that astonishes their white employers."
"The Pearl Oyster Fishery, which targets the Silverlipped Pearl Oyster (Pinctada maxima)
comprises both wild-caught and hatchery-reared oysters. Diving for pearl oyster wild stock
occurs mainly along Eighty Mile Beach, ideally in water depths less than 20 m"
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| A diver is assisted into the water by three deck hands from a pearling lugger. Thursday Island, Australia. 1948. courtesy: Frank de Langhe, facebook |
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| It is highly unlikely, given all of the above that Koombana would likely be south of a hypothetical line east of Bedout Island where water depths equate with 30m and less; without even having to take into consideration the improbability of such a large steamer negotiating the Amphinome Shoals without grounding. |
Gas exploration vessels predominate in the area of interest but although activity has been prolific in short bursts (as observed on vesselfinder over an extended period of time) the finding of a wreck or debris field has not been reported by this quarter. One would hope that anomalies found would be shared and explored by marine archeaology experts under the guidance of Dr Anderson.
https://3denergi.com.au/projects/offshore-bedout-wa/
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| During March (2024) there was a great deal of vessel activity in the zone of interest surrounding Captain Upjohn's coordinates (marked one to thirteen on image). According to 'vesselfinder' these were reported as fishing vessels but after some investigation it appears that these vessels were in fact allegedly connected with the gas and oil industry. |
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| 19 - 24 August (prior to this, for months, no significant vessel activity in this zone) |
Captain Irvine made an interesting comment during the time of the search for Koombana that she was unlikely to be found 'south of' Port Hedland. We can speculate as to the rationale of this statement but given it as it stands there was not a belief that Captain Allen steamed west due to concerns about weather conditions.
Captain Irvine, chief harbormaster, hasbeen in conference with representatives ofthe steamship companies at Fremantle, andhaving charts available, is arranging acourse as deemed most advisable.Regarding your enquiry as to the search beingmade south of Port Hedland, Captain Irvinepoints out that the Bullara passed near thecoast from Cossack to Port Hedland, alsothat a number of luggers are out. He doesnot think there is any probability of asuccessful search being made south of thatport.
In conclusion, I believe Koombana will ultimately be found NE Bedout, taking into account the factors outlined and dependent on success of an airborne mag search identifying a significantly intact Koombana wreck hull. If Koombana broke up or her hull has collapsed this will be more challenging but within the realm of expert data analysis.
https://www.mmaoffshore.com/mma-news/mma-awarded-department-of-defence-contract
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