(The Searches for SS Koombana, Kerry Thom)
There is a different way of looking at this conundrum and an important correction to be made.
Therefore, Captain Upjohn had a far better idea where Bedout Island was in relation to his ship and the various wreckage discoveries than is implied by the quoted "27 to 37 miles".
The answer to this, in part, can be derived from the Inquiry transcript which in turn illustrates the potential inaccuracies in newspaper reporting. The following extract is drawn from the Koombana Days online site, a truly helpful resource:
Did you take any samples of this oily substance?
- Yes, two or three dozen bottles.
What depth was there at this place?
- 30 or 35 fathoms. 55 m - 64 m (mean 59.5 m / 195 ft.)
Did you see any trace of the vessel at that depth? There would be nothing to indicate that the Koombana or any other vessel would be there?
- It was getting dark and it looked like the outline of a vessel. The Chief Officer said "It must be one of her decks," I said "No, the decks would not look like that." I could see no more. The engines were stopped and we drifted about 4 miles."
What was the stuff in the bottles?
- Oily, greasy water.
Have you any idea as to how that came there?
- It looked as if it came from a wreck.
There would be stuff on a ship to make this?
- Yes.
Where are these bottles?
- At the Company's office.
We will produce these if desired.
Mr. Dowley. You saw this at dusk?
- Yes.
'It looked like the outline of a vessel' does not come any more graphic or compelling than this!!
Why?
Reluctance to be the one pin pointing the site of the wreck of Koombana? Magnetic ore in bedrock interfering with compass readings and dead reckoning?
If one examines the navigation chart for Bedout Island (see link below), only when plotting a position to the northward of the coordinates, 1.85 miles, bearing 2.55 degrees, does one get an average depth between 30 and 35 fathoms = 33 fathoms; 200 ft.; 61 m.
Referring to the image below we see that there are 3 options for this depth in the vicinity of the original oil patch coordinates, the depth of which is 164 ft. (50 m; 27.3 fathoms).
The far bottom right figure of 180.4 ft. (55m) is 27.5 miles, bearing 45.38 degrees from Bedout Island, which is the closest we get to Captain Upjohn's estimate of 27 to 28 miles from Bedout Island.
The upper 187 ft. mark is 30.9 miles from Bedout Island, which is well beyond Captain Upjohn's 27 to 28 miles estimate and 7 ft. deeper.
The 180.4 ft. mark to the left is only 25 miles from Bedout, short of the 27-28 miles.
courtesy i-boating |
courtesy i-boating, navigation charts. |
27.5 miles = 19 15 51 S, 119 26 48 E 25 miles = 19 12 19 S, 119 17 22 E |
If we are to nitpick given that Captain Upjohn's coordinates are basic in terms of omitting 'seconds' we can extrapolate an outer range for the original coordinates with a bias towards the 27.5 mile mark = 1.25 miles deviation.
Therefore, the 27.5 mile mark can be considered to be either 4 or 5 miles from the original coordinates.
What is fascinating is that the bow plank etc discovered '20 miles' north of Bedout Island is 19.7 miles from the 27.5 miles position as per image below, rather than the 18.4 miles to the original coordinates. Captain Upjohn referred to it being 20 miles. He also referred to the bow plank etc. being 20 miles north of Bedout, which it WAS!!
How close can one get!!!!
It does seem progressively compelling that the position marked 27.5 miles could very well be our target of interest - a resting place for the steamer Koombana; a section of seabed predominated by sand rather than coral and shells (not a target for pearlers or incidental discovery).
Also note that the bow plank etc is almost due west of the 27.5 mile mark - within the parameters of the post-cyclone westward trending current.
It is interesting that Captain Upjohn decided to collect as many bottles as 'two to three dozen' stressing the importance of the find and that the bottles, according to the outcome of the Inquiry, stayed at the Company's offices.
If we take a closer look at the distribution of wreckage discovered (1 - 11), there is further compelling reason to pursue this potential site of the wreck of the lost RMS Koombana:
Important to note that Captain Upjohn discovered a spar awning and plank close to the oil patch coordinates, in effect the true starting point. |
courtesy: https://3denergi.com.au/projects/offshore-bedout-wa/ |
There is a further option depending on the 'steamer track':
The steamer Albany, 1898:
"At noon on Friday Bedout Island was passed about 6 miles out."
If we are to return to speculation, it is generally assumed that if Captain Allen had decided to follow the standard course rounding the northern aspect of Bedout Island, given the gale force winds and long rolling seas coming up from the southwest, he would likely have given the island a sensible 10 mile plus clearance (some say about 9.5 miles).
But what if visibility was still good and the worst of the cyclone was bearing down towards Balla Balla some 100 miles to the southwest, he might have done what was described by the extract above, passing Bedout Island '6 miles' out. The risk factor vs. getting as far away from the cyclone conditions as fast as possible, if you will...
If this hypothetical case is true we might need to review the trajectory from a 6 mile clearance point heading towards Gantheaume Light (Broome). An interesting picture emerges of the steamer track Koombana would have followed before disaster suddenly overtook her.
If this hypothesis has merit, we are looking at a potential search block significantly further south of the original coordinates - some 8 miles, in 53-63m water, depending on tidal variations.
In fact, the wreck might lie significantly to the south of the presumed track and should be factored into future searches.
In the quest to find Koombana NE of Bedout one must also not lose sight of the possible coordinates deviation factor (James Martin, 10.5 miles further out).
All factors considered one hopes that ultimately a broad airborne magnetometer survey will reveal Koombana's final resting place whether she be intact or a significant debris field.
No comments:
Post a Comment