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David G. Brown
Member
Username: brown
Post Number: 1946
Registered: 12-2000
| | Posted on Tuesday, April 17, 2007 - 1:51 pm: | 
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There are two "logs" kept. One is the rough log, often just notes usually kept by the junior officer. The other is the "smooth log," or the official log of the voyage. It is traditional at the end of a watch to enter the rough details into the official log so there are no errors or omissions. It may also be that the inconvenient details are not recorded during the "smoothing" of the rough notes.
What we do not know for certain is the timing of the transcribing of the rough log. Did it happen in conjunction with the change of watch for the senior officers? or the junior? Depending, the official log would be up to date as of either 8 p.m. or 10 p.m. If the earlier time, we would not have the 7:30 stars as they were not completed as of 8 p.m. However, both updates would contain the dead reckoning for 8 p.m.
Sam's drawing is excellent, and is accurate within the "circle of confusion" surrounding any positioning done using 1912 methods of navigation. However, I believe he has the location of the DR of the accident too far east by almost 9 miles. This discrepancy between our impact positions is due to our ongoing argument over the duration from "The Corner" to the accident.
To the uninitiated, Sam and I are in perpetual--but friendly--argument over time. He follows a straight-line reckoning with the 8-to-12 watch not yet having served its 23/24 extra minutes. I believe those extra minutes had already been served in the 10 p.m. hour prior to Murdoch coming on duty. During those 23/24 minutes at issue, the ship would have gone almost 9 miles westward, putting Titanic's dead reckoning west of 50 West longitude.
This is more critical than it appears. Depending upon whether you use my DR or Sam's completely alters the surface current drift. I show a generally easterly drift. Sam's plotting produces westerly drift.
A westerly drift is out of keeping with the historical and oceanographic records for that area. The following information comes from a 1926 edition of Bowditch:
"525. After passing beyond the longitude of the easternmost portions of North America, it is generally regarded that the Gulf Stream, as such, ceases to exist; but by reason of the prevalence of westerly winds the direction of the set toward Europe is continued until the continental shores are approached...
528. The Arctic or Labrador Current sets out of Davis Strait, flows southward down the coasts of Labrador and Newfoundland, passing the eastern shoulder of the Grand Bank and to a variable extent beyond, according to the season, into the region between the parallels of 41 and 42 of latitude where, upon encountering the Gulf Stream drift, it turns to the eastward, acquiring a movement parallel with the direction of progress of the Gulf Stream waters toward the northward and eastward."
Currents are not totally predictable. There is nothing which would absolutely prevent westerly drift in the vicinity of the accident on 14 April 12, but the history of current in the area makes a westerly drift highly unlikely. By my reckoning of the duration from "The Corner" to impact, however, the appropriate (and expected) easterly drift appears. Due to the easterly drift of the surface current in the area, I believe Titanic did not get as far west as its dead reckoning would indicate. My guess is that for practical purposes Titanic and the berg met at 50 West longitude. It continued an easterly drift until sinking.
Surface drift does not have to be the same as the current drift at depth. We can observe from the coal "smear" on the bottom that the subsurface drift that night was apparently almost due south.
Sam's map indicates a simultaneous southerly drift on the surface of about 1.25 knots. This can be reckoned by dividing the distance in miles between the latitude of the sinking and the latitude of the accident by the duration of the sinking. This seems a bit large, but not impossible. If we properly extend the duration by adding the time the wreckage took to hit the bottom, the drift comes down to a more believable speed for flat calm water of under 1 knot. We must use this longer duration because the wreckage continued to be affected by current until it fell into the mud on the bottom.
The easterly and southerly components of drift did not occur in isolation. Rather, they took place simultaneously. And, they would have affected the navigation of ship's coming to Titanic's aid. This could have placed the reported DR longitude of the wreckage too far west and south. (Remember, the wreckage should have drifted easterly in the historically recorded currents for the area of the wreck.)
The distance between the latitude of the wreckage to that of the reported wreckage indicates a southerly drift of 1.2 knots. While possible, it is about 0.4 knots larger than should be, again reflecting a DR uncorrected for the effect of current drift.
My guess is that the real location of the wreckage was on the longitude of the wreckage and about three miles north of the latitude given.
All-in-all, Sam's chart is accurate enough to prove that Californian's position was not as claimed by Captain Lord. Sam is, in my view, being extremely kind the Californian's captain. Using my version, Lord looks even worse.
And, Sam and I will continue arguing over times, both time of day and duration. I presently see no way to solve our disagreement as both of us lack the same facts necessary to "prove" things one way or the other. What we don't know about some aspects of the ship's navigation far exceeds what we do know. There is nothing wrong with a good academic argument as long as it generates more light than heat.
--David G. Brown |
Ellie-Amber Taylor
Member
Username: alainn_mactire
Post Number: 17
Registered: 4-2007
| | Posted on Tuesday, April 17, 2007 - 4:05 pm: |
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Wow, detailed stuff David 
I do find the whole "mystery ship" point very interesting. Both theories sound plausible, but yes I quite agree, good academic arguments are all good as long as they don't get out of hand
Bíonn dhá insint ar scéal agus dhá leagan déag ar amhrán.
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Samuel Halpern
Member
Username: cmdrsam
Post Number: 1531
Registered: 3-2003
| | Posted on Tuesday, April 17, 2007 - 8:24 pm: |
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I think a little clarification concerning log books may be needed here. In Rule 111, which I posted above, there was a paragraph that said: "Collisions and similar occurrences should be briefly entered in the Official and Ship's Log-books."
It should noted that these are two different log books that were required to be maintained. The "Official Log-book" was kept by the Commander (Smith) and was distinct from the ordinary "Ship's Log-book." (IMM Rule 103.) It had to conform to government regulations which were printed within it.
The Ship's Log-book, which conformed to IMM rules, was the responsibility of the Chief Officer (Wilde) who was required to write it up every day. (IMM Rule 215.) The entries entered by the Chief Officer had to be initialled by each watch officer and then submitted to the Commander to sign off on. (IMM Rule 216.)
The Officer of the Watch, OOW, (which rotated every 4 hours from 2/O Lightoller, to 1/O Murdoch, to C/O Wilde) was responsible for noting everything of importance in their watch on deck on what used to be called the "Log Slate," or more commonly the "scrap log." All data required for the navigation of the vessel was noted in the scrap log which was required to be written up every Watch by the OOW. (IMM Rule 257.) The actual written entries in the scrap log were made by the fifth (Lowe) and sixth (Moody) officers who actually wrote the details down as they occurred, including calling up the engine room to get the number of revolutions carried over the last 4 hours. The OOW was responsible for seeing that all this was done. These scrap log entries for all 4-hour OOW watches were then written up by the Chief officer in the Ship's Log-book once each day. My guess is that Wilde did this after come off duty as OOW at 6 am after taking breakfast.
There were other log books on board as well. There was a Quartermasters log book where the taffrail log readings were recorded every two hours by the stand-by QM when they were telephoned to the bridge by the QM stationed out on the poop. (The 3rd QM was at the wheel.) Also the temperatures of the air and sea, and the barometer readings. All these were transferred from the QM's logbook to the scrap log every 4 hours.
Dave mentioned the 8 pm DR. There was also what was called the Night Orders Book which was written by the Commander in ink that had the course to be steered and all other necessary instructions, including circumstances when he was to be called, that was given to the OOW. These orders had to be initialed and followed by the OOW. This book was passed from one OOW to the next during the nighttime hours. A requirement was added that the ship's position for 8 pm ATS was to be entered into the night orders books (IMM. Rule 118.) We know this position was worked up by 5/O Lowe between 6 and 8 pm and given to Smith on the night of Apr 14th.
The Chief Engineer (Bell) was required to maintain the Engine Room Log-book which included times and orders received from the bridge, the temperature of engine rooms and stokeholds at the beginning of each Watch, the quantity of coal consumed and remaining from noon to noon each day, etc. This logbook had to be submitted to and signed-off by the Commander each day. (IMM Rules 413-415.)
Alterations were forbidden to be made in any of the logbooks. If something was lined off, it had to be initialed.
There was also a separate log kept by the Chief Engineer for the refrigeration holds were the temperatures were recorded every 4 hours.
As a separate item, the ship's position and daily progress (distance run) on a track chart was posted in 1st, 2nd, and 3rd class companion ways each day shortly after the noon position was worked out. It was these daily run numbers that 3/O Pitman submitted in a memorandum to the American Inquiry.
There are no Unsinkable Theories.
Sam Halpern
40° 23' 50'' N, 74° 13' 55'' W.
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Michael H. Standart
Moderator
Username: mstandart
Post Number: 12524
Registered: 12-2000
| | Posted on Wednesday, April 18, 2007 - 4:17 am: |
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>>Wow, detailed stuff David <<
David and Sam alike thrive on "detailed" and I think that Titanic research has benefitted because of that. I've been following their discussions and debates for years and have found both to be illuminating. If they differ...and they do...I think it's because there are enough gray areas in the navigation of the time to make it just about impossible to find the one thing that would settle it once and for all. The people who were there weren't using GPS and they made enough mistakes of their own that trying to sort it out is not a game for the mathamatically disinclined.
If you want to learn something, keep an eye on these guys. One of them could be right, but both could also be wrong and they're both smart enough to know it and wise enough to admit it.
Even with that, my bet is that they're both a lot closer to the reality then most other contenders have come over the years.
Cordially,
Michael H. Standart
Equal Opportunity Curmudgeon
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Samuel Halpern
Member
Username: cmdrsam
Post Number: 1536
Registered: 3-2003
| | Posted on Thursday, April 19, 2007 - 12:02 am: |
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I hope my above post regarding logbooks was more enlightening than confusing to readers. Now to respond to my good friend Dave Brown.
The position I showed for the stopping point of the Titanic, 41° 47'N, 49° 56'W, is not within a circle of confusion caused by 1912 navigation methods. The location has nothing to do with the way the Titanic was navigated.
The stopped location was based on just two known inputs; one is the location of the wreck site at 41° 43.5'N, 49° 56.8'W taken at center of the boiler field. The other input was the reported location of wreckage for 11:20 a.m. Californian time on Apr 15, 1912, at 41° 33'N, 50° 01'W. This last location was given by Capt. Lord and entered by C/O Stewart into their log book based on a noontime observation of the sun that showed the Californian at 41° 33'N, 50° 09'W, when coming out of the field ice on the western side after resuming her voyage to Boston. This noontime location can be confirmed by Capt. Hattorff of the SS Frankfurt which had the Californian in sight ahead about 5 miles off his port bow as the latter was exiting the pack ice at that time. The Frankfurt, heading SE toward the spot that the Californian came out of, was reported at 41° 35’ N, 50° 15’ W at 15:20 GMT, one minute before local apparent noon for that particular longitude on that date. It should also be pointed out that the longitude given by Capt. Lord for his noon position on the western edge of the pack ice is just about the same as the longitude reported by Capt. Moore of the Mount Temple when Moore took a Prime Vertical sight of the sun on the western edge of the ice field earlier that morning.
The heading of the Californian when she left the wreckage was N89°W (271°) true. The time from when they left the wreckage to taking that noon sun sight was 51 minutes. The distance from the reported wreckage position to their noon position works out to 6 nautical miles steaming at 7 knots almost due west over ground. Capt. Moore had reported the width of the ice field as between 5 to 6 miles. Lord testified that was about 5 miles wide in width down there. All the data here fits together perfectly.
Now with the wreckage position fairly well established, and now that we know the location of the wreck site with absolute certainty, it is very easy to work out the average set and drift of the surface current over the 9 hours between the time Titanic foundered and the time the Californian left the scene of the floating wreckage. That surface current set and drift works out to 197° true at about 1.2 knots, a number in good agreement with what was written in the 1992 MAIB Reappraisal Report.
To get to the Titanic’s final stopping point we only have to apply this current in reverse for about 2 ½ hours, the time that the Titanic remained afloat before she sank. The result 41° 46.6’N, 49° 55.6’W which I rounded to 41° 47’N, 49° 56’W. (The MAIB report had 41° 47’N, 49° 57’W as the collision point, and used 41° 43.6' N 49° 56.9' W as the wreck site location. Our results are essentially identical.)
Now Dave believes the dead reckoning position of the accident was 9 miles further west than I or the MAIB show. First, let me repeat that dead reckoning has absolutely nothing to do with Titanic’s final stopping point. We don’t need to assume anything about Titanic’s speed or heading here. Second, Dave presented an argument that a westerly component drift is out of keeping with historical and oceanographic records for the area, and quoted a few passages from Bowditch which indicated that Labrador current in the area would take on an easterly drift parallel to the Gulf stream. He guessed that the real location of the wreckage was about 3 miles more to the north of the wreckage latitude given because he believes the surface current would have been under 1 knot.
What I’d like to say about using average current set and drift is summed up in an old Bronx expression which says, “forget about it!” In any given year, conditions can be quite different from expected. Look at the following, http://rads.tudelft.nl/gulfstream/gif/gulf_060401_vel.gif. This is data by modern satellite imagery of current vectors across the Atlantic for Apr 01, 2006. Notice in the region of interest, 41°-42°N, 50°W, how the Labrador is converging with the Gulf Stream and what is also formed is a cold water eddy with counter-clockwise circulation. Now we of course don’t know what this picture would have looked like on Apr 14, 1912, but what we do know is that the ice was seen far to south of where it was expected for that time of year suggesting a very strong, dominant Labrador current. Not only that, but we also have specific evidence submitted at the American Inquiry (submitted May 25, 1912) that freezing surface water was encountered well to east of the wreck longitude beginning about 48° 25’W. This evidence, and the position of a vast field of pack ice ranging for miles from north to south near longitude 50°W suggests a very strong, cold southerly surface current drift dominating the region. The fact that the Californian appeared to be making slightly better than 11 knots over ground before she was forced to stop also suggests she encountered a small westerly component as well which is indicative of some counter-clockwise circulation in the region. The strong southerly drift component in the region that affected the Californian for so many hours well after her noontime sight was taken is what caused the Californian to end up quite a bit south of where Capt. Lord believed he stopped for the night. And we know the Californian had to end up on that line of bearing running from SE to NW true from the Titanic, as show in the chart in my post above, for Titanic’s rockets to have been seen by Gibson and Stone in the direction that it was.
So the issue of the stopping point for the Titanic really has nothing to do with the time issue that Dave mentioned, nor DR positions, nor how Titanic was navigated. It has to do with the location of the wreck site and the now known surface current that affected all vessels that steamed into that region. However, with the stopping point known to the accuracy of this estimate, probably less than a mile, it can be shown that a collision with the iceberg could not have happened 12 hours and 4 minutes past noon on April 14 as Dave believes it did. I believe this weekend Phil Hind will be posting a joint article that Mark Chirnside and I wrote for TIS’s Voyage 59 journal called “Olympic and Titanic: Maiden Voyage Mysteries.” Although the major focus of that article is on the maiden voyage of the Olympic, it also addresses this time issue in part from a purely navigational sense. What it shows is that a collision 12 hrs 04 minutes from noon is inconsistent with what the Titanic was actually doing that night in terms of speed made good over ground from her noontime location, a location independent of any assumptions about speed or course headings. In a separate article in the future I will extend all of this to show not only navigationally is 12 hours 4 minutes not correct, but I will include detailed independent testimonial evidence to show that the collision did indeed occur about 11 hours and 40 to 45 minutes past noon on the 14th of April. In addition, I will show independent external observational evidence that also supports this conclusion as well as the foundering time of the Titanic. The multipart article will also address several time enigmas and paradoxes that have caused so much confusion to so many.
At least the one thing Dave and I do agree on regarding time is that Titanic’s clocks for April 14 were set for 2 hours and 2 minutes ahead of New York time, something which is at variance with three differing conclusions presented in the two inquiry reports and the limitation of liability hearings of 1913. This too is summarized in the paper that Mark and I wrote.
There are no Unsinkable Theories.
Sam Halpern
40° 23' 50'' N, 74° 13' 55'' W.
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Paul Lee
Member
Username: dpl
Post Number: 1746
Registered: 8-2003
| | Posted on Friday, April 20, 2007 - 1:43 pm: |
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Hi Sam,
You're quite right about how the MAIB deduced the Titanic's stopping location. This extract is from their working papers:
http://www.paullee.com/MAIB.jpeg
One thing that jumps to mind; in Discovery of the Titanic, Ballard said that the drift was deduced from the Californian's logbook and it was found to be 0.7 knots, at a heading of SSE. This doesn't quite jibe with the MAIB report.
Paul
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http://www.paullee.com |
Samuel Halpern
Member
Username: cmdrsam
Post Number: 1542
Registered: 3-2003
| | Posted on Saturday, April 21, 2007 - 11:52 pm: |
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What Californian logbook was Ballard really talking about? I understand that it no longer exists anywhere. I have read that statement in Ballard's book some time ago and have questioned where he got his information from. In his book (p.67) he states the Californian drifted 5 miles to the SSE from her stopped position at 10:22 PM the night before on the 14th, to 6 AM on Monday morning on the 15th. That is how he got a 0.7 knot drift. I have never seen any reference anywhere that has Californian 5 miles south of Lord's 42° 05'N overnight latitude by 6 AM from something recorded in her log book except for Ballard. There is no such reference in any of the primary sources that I am aware of.
Ballard also shows the Carpathia lifeboat pickup point very close to 41° 40'N, 50° 00'W in his search area charts in his book. Where did he get that from? He does speak in his book of input from Bill Tantum who had guessed that the wreck should be found close to 41° 40'N, 50° 01'W. Tantum's longitude is the same as the wreckage longitude reported by the Californian. The latitude is also very close to that on the Foweraker chart that is marked "Titanic-struck 11.40 PM" at a latitude of 40° 39'N, just 1 mile north of that.
The Foweraker chart, supposidly based on data from Lord, also showed a 3 mile due south drift of the Californian between 10:20 PM on the 14th, and 6 AM on the 15th, a southerly drift that works out to 0.39 knots. That chart also shows "wreckage at 8.30 AM" at 41° 36'N, and "wreckage at 11.20 AM" at 41° 33'N, all these three points are on the same longitude line but 3 miles apart from each other north to south.
Three miles from 11.40 PM to 8.30 AM is a drift a 0.34 knots. Three miles further drift south from 8.30 to 11.20 is a drift of 1.06 knots. Foweraker was all over the place with drift.
Those three Foweraker points are the three points on the left side of MAIB working paper extract you provided a link to. That data is from Foweraker, not Lord. At least it gives some insight as to what the MAIB folks had considered.
There are no Unsinkable Theories.
Sam Halpern
40° 23' 50'' N, 74° 13' 55'' W.
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