Navigational Confirmation of CQD Position

Dec 2, 2000
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Michael Koch asked what does BFD mean. It means Big F*****g Deal. (Throw an indifferent shrug in with that)
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In this I can only speak from my own personal experience but crewmen on a ship...unless they're on the watch team...don't always pay very close attention to exactly what the ship is doing. It's entirely possible that a ship could do a series of turns and nobody would think twice about it or even care. It's not that they couldn't notice if they cared to, but if they have other work to deal with, it can be quite a distraction.

Engineers on watch would be concerned with feeding coal to the furnaces, deck crew would be concerned with routine tasks of maintainance and clean-up, and those off watch might be more concerned with getting some sleep or swapping a few lies sea stories with their mates. Unless there was a really sudden and radical manuever at high speed...like the rudder being put hard over...which would result in a noticable heel, it's entirely possible that something could happen and they just wouldn't pay attention.

As to authors not thinking about wind chill, well, it might not occur to them to think about what...to a seaman...is obvious.
 
Dec 4, 2000
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Boxhall really believed his CQD position was accurate. Generally, it is proper in historical research to accept what the people involved said happened than to put your faith in later, second-hand interpretations. That's why I find the theory that Boxhall's final CQD position was "correct" dead reckoning to be attractive. This does not mean that I reject the possibility he made a mistake--just that to me it is more faithful to history if we work from the standpoint that the distance between Boxhall's CQD position and the wreck originated from some other cause.

With regard to any maneuvers, they need not have been severe enough to call attention to themselves. In fact, on a passenger ship it is considered "proper" not to shake up the paying cargo any more than necessary. A shallow amount of rudder applied over a longer time gets the same degree of course rotation, but avoids heeling and centrifugal force problems. Nothing the size and mass of Titanic changes speed quickly. How noticeable would the loss of 5 miles an hour over as many minutues be? Only the men on the bridge and at the engine controls would be aware of such evolutions on a dark and cold night when a sensible passenger was tucked beneath the counterpane.

Starting with the hypotheses that Boxhall's DR position was correct...and that maneuvers can be done without attracting attention...what inferences can we draw from the distance between the final CQD position and the wreck site?

I look at this as a navigational vector problem. A force of some direction and magnitude had to be applied to Titanic for the two positions to be different. Alternatively, a series of small forces of varying magnitude and direction that summ to the larger may have been applied. It is this latter possibility that is probably true. And because there are several different "unknowns" (and maybe a couple of "unknowables" as well) that make it difficult to sort out what really happened.

But, we can still test the above hypotheses for validity by using them to "predict" future events. As I have said, what would a navigator in 1912 do who knew his DR position was correct, but necessarily not accurate? He would take into his lifeboat some means of attracting attention over distance. That way, as the rescue ship came toward the CQD position, he could divert it to the actual site of the lifeboats floating near the wreck site. And, that prediction is what Boxhall in fact did do that night.

The other major inference that can be drawn from the differences between the two locations is that Titanic was "dodging" ice prior to the accident. This is a very broad statement. It could mean swerving around icebergs, but I rather suppose it means avoiding the ice as a whole--bergs, growlers and pack. You don't swerve around that sort of mass of ice, you change course to go outside the danger. And, if this is what did happen, it puts lie to the age-old claims that Captain Smith ignored the ice dangers.

A new problem then arises--if Captain Smith did act to avoid ice that night, why did the surviving officers and crew do such an effective job of hiding his prudence from two inquiries?

-- David G. Brown
 

Erik Wood

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My problem with the notion that the ship was avoiding ice is that we don't have any proof to support it. What we have is a difference between the final position the ship gave and where the wreck lies on the bottom, we don't have any information that tells why there is a difference.

That being said I have always (and still am) a supporter of the thought that Captain Smith and his Officers not only knew of ice, but where proactively doing something about it. This can't be supported by testimony or anything else. We have to ASSuME that the men driving the ship that night had better sense then history and the traditional story has given them.
 

Erik Wood

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In addition let me add some more:

Most of accident investigation involves assumption, you have to assume some things you don't know in order to as Dave Brown said, predict future events and fit them into a larger piece of pie. This is a easy thing to do when the ship is still afloat.

Titanic is a completely diffent story. We have no ship or no log to provide us with the actions of the bridge that resulted in the loss of the ship. We have only one surviving officer who was on watch during the event, and two quartermasters who not only give us different testimony but where really in no concrete position to know what had happened and why. So the logical assumption is to go off the word of the man at the wheel not the man at the compass platform and use his testimony to guess at what the First Officer was doing in order to avoid or minimize damage. After all, he was the one carrying out the orders of the men that didn't survive to tell the story.

But then you have Mr. Olliver not calling Hitchens a liar but telling the court things that the man at the wheel didn't mention. How could that be?? Things that could prove that Mr. Murdoch successfully saved the stern from damage, this is supported by the damage known to exsist.

My wife of all folks suggested to me that perhaps when Hitchens said hard a starboard he meant going to the right, which would support Olliver. I think we can rule this out by remebering that the ship was moving to the left as Fleet was on the phone to the bridge. Which, adds another problem.

What is the time difference between the time the lookouts rang the bell and the ship struck ice?? 10 seconds, a minute?? We don't know with any certainty, so we have to go off the person who didn't see anything but heard the bells and felt the impact. This man had enough to time to get off the compass platform and appear on the starboard side of the bridge which is probably at least a 50 second walk.

One of the other problems we face in saying that Titanic was manuvering prior to it's allision is that most people don't understand that as Dave Brown said, passenger ship Captains and Officers know very well how to change course or manuver without effecting the passengers, that is partly how they make there money, by giving folks the scenary of being at sea without the feel of it.
So the ship could have been manuvering, but nobody may have known it, so we are stepping out onto a branch.

So in my opinion and opinion only (not professional) is that yes the ship could have manuvered without passengers being made aware and as Mike said with the crew not really caring.

On a side note: I usually feel course changes and changes in direction of the ship. Unless I know of a directed course change that feeling is followed up by me calling the bridge.

So from a accident investigation point of view, what do we know?

1. Titanic hit an iceberg AFTER receiving a warning from the lookouts.

2. The ship moved to the left BEFORE hitting the iceberg.

3. Damage stops at Boiler Room 5, suggesting a rounding manuver was attempted and completed to clear the stern. (Especially if left rudder was on as the initial order).

4. Neither quartermasters, or lookouts (regardless of how the questioning at the inquiries was aimed) mentioned any manuvering prior to the orders given that are possibly reaction to sighting the iceberg.

5. FULL ASTERN was ordered and recinded to ALL STOP. (FULL ASTERN did not have any time to take effect nor did the ALL STOP command).

6. The ship was operating at around 75RPM or 22 knots.

7. First Officer Murdoch successfully ordered and closed the watertight doors.

Now for a different list, what are the things we DON'T KNOW:

1. The exact location of the Captain during and before the incident.

2. The location and purpose for Fourth Officer Boxhall being away from the bridge prior to incident 20 minutes before the end of his watch?

3. Under whose order did Quartermaster Olliver trim the lamp on the compass platform?

4. The exact course in which Titanic was steaming.

5. The intentions of the Captain because of the known ice.

6. Orders (if any) given to First Officer Murdoch by Captain Smith regarding the ice.

7. Intentional (if any) course changes or alterations prior to 2340 and under whose order where they given.

8. For Fact was a port round ordered.

9. The exact time from the moment the lookouts rang the bell to the time the ship allided with the berg.

10. Exact speed of Titanic.

11. Size of berg.

12. Distance from berg to the ship when first spotted.

13. Density of ice with in a 5 mile radius of Titanic and the berg.

These are just a few of the questions that need to be answered by can't. All of these things that we don't know are all of the things that would make this an easy case to close. Notice that the things we don't know list is longer then the list we do know.

The Titanic has been and always will be a fine mystery. But I think Dave Brown is on a road that will show things in light that more mariner would understand, whether those who love the romantic story will understand it then I don't know that it will make a wave big enough.
 

John M. Feeney

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Sep 20, 2000
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It means Big F*****g Deal

Etymology Note: For those unfamiliar with that particular Victorian parlance, that's "Farthing".
"Big Farthing Deal" -- a phrase analogous in meaning to the German-derived "Three Penny Opera", which generally describes a "much ado about nothing" type of production.
("Big farthing", of course, is an intentional oxymoron, similar to "jumbo shrimp".)

Yeah, and if you believe that one ... ;^)

Mike: Looks like I owe you one large, non-abrasive cloth (for the book quote).

Cheers,
John
 
Dec 6, 2000
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Erik said:

>On a side note: I usually feel course changes and changes in direction of the ship. Unless I know of a directed course change that feeling is followed up by me calling the bridge.

However, as an officer on the ship itself, Erik is not 'normal', knows more than the average customer, and is being paid to keep abreast of changes in the ship itself.

I went on a cruise liner a year and a half ago, and could not *feel* any change in direction whatsoever. In fact, the only time I could 'feel' the ship, was when laying on my bed, when I could feel a very slow roll port to starboard. I will admit that a current cruise liner, is not a ship of 1912.
 
Dec 2, 2000
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No sweat John. Just send the cloth to the local police station addressed to "The World's Most Armed and Dangerous" They'll know who to give it to.
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Bill, it sounds to me like you enjoyed the benefit of real time weather reports...which allows cruise ships to avoid some really nast weather...and the fin stabilizers which smoothed everything out. I suspect you would have done pretty well on an Olympic class liner though. (Provided you didn't throw icebergs or mines into the mix.) While they didn't have the technical bells and whistles of today, by every account I've ever heard, they were good stable ships. Far better then what a lot of people offered.
 

Erik Wood

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I am not "normal"?? Well my wife would agree with you. Seriously though, Bill is right. I am trained and expected to do that. I agree that your average passenger probably wouldn't feel routine course changes if they where done the right way.
 

John M. Feeney

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Erik: Just wanted to congratulate you on that excellent forensic breakdown. I have to agree that while there are certain things we know with relative surety regarding the Titanic, there are a good many that are only "resolvable" via conjecture. (Naturally, some of these hypotheses are more palatable than others, but in the end they're all largely unproveable.)

I do think -- though I'd prefer to be able to model mathematically just how *much* spontaneous course deviation (or how many "swerves") would have been required to account for 13 miles of total difference in forward progress -- that evasive action due to ice encounters could have played some role. (George Behe's book -- "Titanic: Safety, Speed, and Sacrifice" -- does an admirable job of presenting the evidence supporting Fleet's remarks that suggest some previous "dodging" efforts, and also proposes with a good deal of finesse the possibility of corporate coercion by White Star in order to have certain individuals "dummy up". Hichens' own letter -- "... no job, no dole ..." -- to his brother[?] at the time of his murderous assault in Tornay on the man who'd sold him his boat at least strongly *implies* to me that he'd once been promised things that were ultimately not delivered.)

But as for the idea that Boxhall's assurances about the correctness of his calculations specifically point the way to any particular "solution" for the obvious difference in the positions, as David seems to be suggesting, I'm as inclined myself to perceive that as a potential case of "Garbage In, Garbage Out" [GIGO] or possibly "bugs in the computer". Boxhall need only have done his calculations with diligence, working with the best information available to him, to have considered *them* correct. That doesn't at all guarantee that his *result* was even remotely accurate; all Boxhall really knew was that Rostron did find the boats, so his math must have been "good enough". (Of course, If Rostron had instead been coming from the west, like Captain Moore, the outcome would have been very different, and I have to suspect, in that case, that Boxhall's "certainties" about his calculations would never have arisen.)

Some explanation is certainly required. And I don't believe that Captain Collins' own speculation -- that the ship simply moved over time from its original CQD resting place -- is at all feasible. But what exactly is embraced as the likely cause of the discrepancy is probably far more dependent on an individual's own conception of "reasonableness" than on any specific mechanism supposedly being "identified" via Boxhall's proclaimed certainty. Dave Gittins' approach to this error is quite lucid and amazingly credible in my mind. (And Boxhall, as we know from other discussions here, was likely ill and possibly fairly exhausted at the time, so a minor mistake such as Dave proposes isn't at all out of the question, "crack navigator" or not. As Boxhall himself admitted, no one had ever *checked* his calculations, nor was anybody expected to.) I also still entertain the possibility that some time confusion -- Had the clocks been set back or not? -- might potentially have thrown Boxhall's calculations off by 23 to 47 minutes. (Again, GIGO.)

But you're right. We can't know for certain. It's one of the frustrating limitations of the testimony that we were originally presented with accounts that seemed to confirm Boxhall's CQD -- to the extent that Captain Knapp, during the US Inquiry, simply regarded those conflicting accounts from other ships as "mistaken" when he mapped the disaster locale. Only much later were we presented with Ballard's discovery of the actual wreck, and by then few, if any, of those directly involved during 1912 were still around to question on this.

Cheers,
John
 

Erik Wood

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John, thanks for the kind words, I agree with most of what you wrote.

My personal opinion is that Boxhall thought that he was correct in his calculation and he had no reason to think otherwise. As John said he used the best information he had and recontructed the best he could. Whether he was right or wrong isn't IMO the point. He was correct in his own mind and I think that the calculations where right based on the information that he had.

I think that Johns second to last paragraph sums up my thoughts on Captain Collins work. That is not to say he doesn't raise a couple good points, but I just don't agree with his entire theory. Much like the no iceberg thing.
 
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I'm curious about the speculation about Boxhall being confused by the time change, or lack thereof. I would give Titanic's de facto navigation officer a bit more credit than that, especially since he worked his calculations in the same room where the Magneta system master clock was located.

Parks
 
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Titanic's 23 minute clock setback has been one of my areas of study for about three months now. From what I can see, it had nothing to do with the navigation and/or Boxhall's final CQD position. Even if Titanic did get under way again, it was stopped again prior to the clock setback. Thus, all of Boxhall's navigation was done in April 14th hours. There would have been no confusion on his part.

--David G. Brown
 

Paul Rogers

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Apologies for jumping in; I just wanted to make a quick point.

John said: "Dave Gittins' approach to this error is quite lucid and amazingly credible in my mind. (And Boxhall, as we know from other discussions here, was likely ill and possibly fairly exhausted at the time, so a minor mistake such as Dave proposes isn't at all out of the question, "crack navigator" or not.)"

I couldn't agree more. I would find it more surprising if an error hadn't been made, what with Boxall allegedly unwell and certainly under enormous pressure.

I work as a trainer for a UK Financial Adviser company, my main role being to train new staff on the UK tax system. At the end of their training, everyone sits a three hour exam which is mainly calculation-focused. Once a year, everyone in the company (including me) sits a similar three hour exam, to guard against "knowledge fade." The calculations are quite in depth, but still relatively easy if one understands and applies the theories being tested.

Despite having trained out these topics week-in, week-out, on my last paper I still managed to drop 4 marks in one question, whilst completely misreading another. (Thankfully, I spotted the latter error whilst doing a final check before handing in the paper. Otherwise it would have been very embarrasing!) Other colleagues suffered similarly - most certainly not from any lack of knowledge but just because mistakes happen.

This is why I think Dave Gittins' theory is so believable, even without any personal knowledge of navigation.

Paul.
 

Erik Wood

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I have not read Dave Gittins theory but from what I have heard of it described by John it sounds like a more then reasonable theory. I will have to try and find his website and look for it.
 
M

Markus Philipp

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Hi all,

I think it is worth to study Dave Gittins theory. Personally I am quite convinced that this is the "correct" explanation for Boxhall's error.

Boxhall used 22 knots for his calculations. This speed estimation comes close to reality.

1. From Saturday noon to Sunday noon Titanic made 546 miles. The clock was retarded by 44 minutes in the previous night (Pitman's memorandum).
Speed: 546 miles / 24.7 hours = 22.1 knots.

2. At Sunday noon Titanic was 126 miles before the corner. The position of the wreckage is 133 miles behind the corner.

Speed: 259 miles / 11 hrs 46 mins = 22.0 knots. (Boxhall used 11.46 as time for impact)

Even if we assume an easterly current of 1 knot Titanic's position would have been 2 miles west of the wreck position.

Speed in this case: 261 miles / 11 hrs 46 mins = 22.18 knots.

Thus Boxhall was perfectly justified to use 22 knots in his calculation.

Now, what went wrong with his calculation?

Lightollers star position was taken at 7.30 p.m.
Time from 7.30 p.m. to 11.46 p.m.: 4 hrs 16 mins

Titanic travelled 22 knots * 4 hrs 16 mins = 93.9 miles.
Course was south, 86° west. 93.9 miles have to be split in southerly and westerly component. Boxhall used traversion tables for this, and he found:

93.9 miles * sin 86° = 93.6 miles west

93.9 miles * cos 86° = 6.55 miles south

No error occurred up to now. To find the final longitude Boxhall now had to convert 93.6 miles into increase of longitude at latitude 42°. Mathematically spoken, he had to figure

93.6 miles / cos 42° = 126' = 2°6' degree of longitude.

Unfortunately he slipped into the wrong column and used sine instead of cosine:

93.6 miles / sin 42° = 140' = 2°20' degree of longitude, which is 14 minutes of degree more.

He found 50°14' west. He would have found 50°00' west, with correct calculation. This is just 2 miles besides the wreckage position.

When we look at the traverse table which he used to divide by sine or cosine we can easily understand how to slip into the wrong column. The same table could be used for different calculations. The same key word "Departure" appears in bold letters in one column and in cursive letters in the other one. Depending of the type of calculation he had to use the bold or the cursive key words to find the right column.

Diff. Long. . . Departure
Distance . . . Diff. Latitude . . . Departure

121 . . . . . . 89.9 . . . . . . . 81.0
123 . . . . . . 91.4 . . . . . . . 82.3
124 . . . . . . 92.1 . . . . . . . 83.0
125 . . . . . . 92.9 . . . . . . . 83.6
126 . . . . . . 93.6 . . . . . . . 84.3 correct result here: 126
...
140 . . . . . .104.0 . . . . . . . 93.7 wrong result here: 140

Instead of 93.6 in the second column he looked up 93.7 in the third column. Thus he found 140' instead of 126' minutes of degree longitude.

This is why I think Dave Gittins' theory is so believable.

Markus
 

Dave Gittins

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Nice work, Markus!

After I created that web page, I learned that in 1912 officers were taught to convert miles of departure to minutes of longitude by a calculation much like you suggest. I regret that I didn't copy the details. The Board of Trade expected a lot of navigation to be done by trigonometry and logarithms.

I can't recall the exact method, but it would have been as you suggest, except that the division was done by means of the logarithms of trigonometrical functions supplied by the books of nautical tables. I don't know if they made a correction for the fact that the earth is not perfectly spherical.

Like my idea, your method produces a small error at latitudes of about 45°. If you rework if for 20°, you'll see that the result of using the wrong trigonometrical function is obviously silly.

Another quite simple possible cause of the error is that Boxhall worked from a dead reckoning position for 8-00 p.m. instead of the stellar position. He thought this unlikely, because he was working from his own notes, but you never know. The poor devil was tired and possibly unwell.
 
M

Markus Philipp

Guest
Hi Dave,

your page and my idea that Boxhall switched sine and cosine rose independant from one another. At school I have learned to use logarithm tables. From this I got the idea that the same column might be used for some angle phi or (90° - phi). I played with 42 and 48 degree and found that the error would match the distance between CQD and wreckage. But I did not know what kind of tables the navigators really used. So it was just a weak idea. Later on I found your page, and you presented the tables which navigators use, and this is all the way a perfect confirmation of my idea.

You said: "another quite simple possible cause of the error is that Boxhall worked from a dead reckoning position for 8-00 p.m. instead of the stellar position. He thought this unlikely, because he was working from his own notes, but you never know. The poor devil was tired and possibly unwell".

Maybe. But where did he get the dead reckoning position at 8 pm from?
There is an interesting arguement between Lowe and Senator Smith in the US enquiry. Lowe explained that Titanic was 162 miles (sic) before the corner at noon. I think this is a typo, because 162 miles by 6 hrs makes 27 knots, which is quite unlikely. It must be 126 knots.
And one can find from Lowe's testimony that 126 miles is the correct value. Lowe said that he estimated the position at 8 pm. He used a speed of 21 knots for that. He even made a calculation on a chit of paper and figured 20.95 knots! From his tales one can hear that he must have divided something by six hours (noon to 6 pm) and found 20.95 knots. What did he figure then?
20.95 knots * 6 hrs = 125.7 miles. There we are with 126 miles (and not 162!) before the corner.
Lowe found 21 knots because he put the time of the turn at the corner to 6 pm: 126 miles / 6 hrs = 21 knots. But he should have calculated: 126 miles / 5 hrs 50 mins = 21.6 knots, or 126 miles / 5 hrs 45 mins = 21.9 knots!
Thus he used 21 instead of 22 knots. In eight hours he will loose 8 miles then. That means, Lowe's dead reckoning position at 8 pm is eight miles east of the correct position at 8 pm.

But Boxhall's CQD is 12 miles west of the wreck position.
I have read somewhere in the enquiry that Lightollers star position was plotted into the chart at 10 pm.
Boxhall in the US enquiry said that Lightollers observations were beautiful. There were three couple of stars for longitude and latitude, and they all agreed.
So I am inclined to believe that Boxhall really used Lightollers star position as base for his calculations. Otherwise there is no need for Lightoller to take precise stellar observations.

Cheers
Markus
 

Jim Currie

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On day 11 of the BOT Enquiry,a great deal of examination into the content of 'the ice warning message from 'Caronia' took place. Mr.Lightholler was on the stand. He stated it was the only message he saw and that he first knew about it at about 1 pm on the 14th. He further discussed it with Mr. Wilde when he relieved him at 6:pm that evening.
That particular message warned that the eastern extremity of the ice was 49 degrees west longitude.
When he went on watch at 6:00pm that night, Lightholler made a quick mental calculation and reckoned that the ship would be at the ice about 9:30pm - half an hour before the end of his watch. However,as a check, he ordered Moody to make a proper calculation. Contrary to Lightholler's timing - Moody calculated that Titanic would reach the ice an hour and a half later than Lightholler thought - at 11:00pm.
You might think that since one calculation was mental and the other was 'on paper' the latter would be the more accurate. It certainly would have been more believable had there been a few minutes of longitude or time different. However an hour and a half or 33 miles is not insignificant.
Lightholler was a very experienced Extra Master. He would, without doubt, know that a ship on a course of 266T travelling at 21.5 or 22.0 knots in latitude 42N would increase its westerly longitude by approximately 29 - 30 minutes every hour. So how come the huge discrepancy? Lightholler dismissed it by saying Moody had probably a different source of information but I do not think so and I don't think he did either!

Is this what happened?


Both men came on watch at 6:00pm.- 3.5 hours until 9:30 pm at say 22 knots is 77 miles which converted to longitude in latitude 42.00N is about 104 minutes or 1 degree 44 minutes of longitude However, 144 minutes is 2 degrees 24 minutes - a difference from Lightholler of 40 minutes of longitude which, converted to miles is 30 miles - just under and hour and a half at Titanic's speed. This would account for Moody's estimated time of arrival at the ice being 11pm instead of Lightholler's 9-30pm.

Lightholler's navigation was again tested at
Q13554 to Q13556 of the Enquiry when he mentally calculated back from Boxhall's 50-14W. CQD to the time of passing 49W. He once again, reckoned his second bit of mental maths agreed closely with his (Lighthollers) original estimate of 9-30pm for Titanic being at the eastern edge of the ice

It follows that if Lightholler's back-calculating to 49 W fitted with Boxhall's CQD Longitude - both men were reading from the same 'hymn sheet'.

In an attempt to work out how Lightholler worked back his estimated time of passing the 49th. meridian I have used two timings - 14th. time and 14th + 23 minute clock change. I term them Run A and Run B.


CQD Longitude = 50. 14 W
Time of Impact= 1140 pm

Lightholler's passing the 49 W time:0930pm(14th).

Run A- 9:30 to 1140
2hrs 10'@22.0 = 47.7 miles D.long 1. 04 E
Run B- 9:30 to 12:03 am (23' set-back).
2hrs 33'@22.0 = 56.1 miles-D.long 1. 16 E
These give:
DR Longitude @ 9:30 pm - Run A = 49. 10 W

DR longitude " " " - Run B = 48. 58 W

Applying a further Run back from 9:30 pm until 6:pm:

Run: 3hr.30min.@ 22.0 = 77 miles- D.Long 1. 44 E
Gives DR LOngitude @ 6:pm for:
Run A = 47. 26 W
Run B = 47. 12 W

Then back yet another 10 minutes to the Turn gives:

DR Longitude @ 5:50pm for Run A= 47. 21 W
for Run B= 47. 08 W

However Longitude of the wreck is 49 58 W

Turn 5:50pm to impact 11:40pm is 5hr 50 min.
@ 22 knots this makes a D.Long of 2 52 E

This gives a DR Longitude @ 5:50 of 47 06 W
This last DR is 128 miles from the wreck site and 5 miles x 240T from The Corner. The distance from The Corner to the wreck site is 133 miles.

The Lighhollers of-the-cuff DR worked-back longitude in Run B above points to him having allowed for the clocks being set back 23 minutes when calculated the distance run from crossing the 49th. meridian until impact. This would be natural since he was in bed when the impact came and would naturally expect the first part of the set-back being carried out. I also suggest that's what Boxhall did as well. How else could Lightholler have suggested that Boxhall's CQD was correct? However, it does not prove that the clocks were actually set back - the position of the wreck points to it not having been done so. To cover 128 miles in 6 hours 13 minutes,(5:50 to 12:03am next morning), Titanic would average 20.6 knots. There has never been any suggestion that she was travelling at less than 21.5 knots. I have a sneaking suspicion that Boxhall and Lightholler both knew she was averaging more than 22.0 knots!