Boxhall's CQD position

[Jim Currie]

Cut the avoiding tactics, Sam.
Smith ordered a turn at a certain time and he based that order on knowledge. The ship turned at that time. Forget about Pitman and Boxhall for the moment, concentrate on building a picture based on happenings.

 

[Jim Currie]

Next questions:

Q3: What course did CaptainSmith set Titanic on from Noon to the turning point at The Corner?
A3: 240.5 True.
Q4: The calculated final course to The Corner turning point on the last bit of the Great Circle Track being followed by Titanic is 236.5 True, so why did Smith set a course 4 degrees to the left of that...240.5 True?
A4: Because at Noon April 14, when the exact position was found by observation of the Sun, Titanic must have been at a position 5.5 miles South East of where she should have been at that time. Smith would then have calculated the true course to point Titanic directly at The Corner.
Q5: What chance was there that Titanic would follow the new course exactly and arrive exactly at the position of The Corner.?
A5: About as much chance as a snowball on a fire-guard.

So far I have not speculated for a second. For those of you who prefer pictures, here is a rough idea of what I am getting at.

 

[Samuel Halpern]

Cut the avoiding tactics, Sam.

I guess you don't want to say or speculate why two of T's officers swore that the ship should have been at the Corner well before the time that was set. Boxhall's exact words were: "Yes, I saw it and I remarked to the Chief Officer between 4 o’clock and 6 o’clock that I considered the course ought to have been altered some considerable time before 5.50 - that is, if it was meant to be altered at the corner, 42 N., 47 W."

 

[Rob Lawes]

I was always under the impression that a ship's position is only as good as it's last fix? All the discussion of the timing and location of the turn to the final course seems a bit 'smoke and mirrors' to me.

What I find strange is that 2 highly experienced navigators couldn't work out the ships position after 4 hours (give or take) in a straight line from a known good fix. Conditions that night were pretty much perfect for taking fixes and for keeping on track. Clear skies, flat seas and light airs. The QM could hold the ship on course with the tips of his fingers.

Boxhall worked up the fix taken at around 19:30. All he needed to know was the speed of his ship and the course to know where they were at 23:40.

That's 4 hours and 10 minutes at, between 21 and 22 knots.

Captain Smith's position was about 20% too far and Boxhall's about 10%. Ships don't end up 20 and 13 miles from a known good fix in 4 hours unless someone screwed the maths.

 

[Aaron_2016]

Is it possible that the Titanic was fighting against the current and both Smith and Boxhall did not realize the current was stalling their progress, and as a consequence they both plotted their ship's position further west?

Similar to this video. Fighting the current.

.

 

[Rob Lawes]

There may have been a current, I don't know in which direction however its unlikely to have been an easterly around 5 knots to produce Smith's miscalculation and around 3 knots to produce Boxhall's.

Putting that into context in terms of current strength, the Bristol Channel has the second largest drop between high and low tides in the world. At maximum flow the current speed is between 6 and 7 knots.

 

[Jim Currie]

I guess you don't want to say or speculate why two of T's officers swore that the ship should have been at the Corner well before the time that was set. Boxhall's exact words were: "Yes, I saw it and I remarked to the Chief Officer between 4 o’clock and 6 o’clock that I considered the course ought to have been altered some considerable time before 5.50 - that is, if it was meant to be altered at the corner, 42 N., 47 W."

You still don't get it, Sam. Or rather, don't want to.
Titanic turned The Corner at 5-50 pm...8-48 pm GMT.
You believe she had 126 miles to run from Noon to The Corner. The minimum average speed from Noon was 20.95 knots (Lowe) The maximum average speed was 22.1 (As per previous Day's Run). It follows that the distance run from Noon to 5-50 pm was between 122.2 and 128.9 nautical miles. This is equal to an overshoot of 2.9 miles maximum if we use your 126 miles to go number. It is a 4.9 miles overshoot if we use the calculated figure of 124 miles.
No skilled Navigator would automatically assume a previous average speed to be a constant. Boxhall used propeller rpm for speed and said so.
Consequently, when mentally calculating ETA The Corner, he was thinking in terms of 21.5 knots...4.9 miles at 21.5 knots would take 13.7 minutes..."A considerable time".

 

[Jim Currie]

I was always under the impression that a ship's position is only as good as it's last fix? All the discussion of the timing and location of the turn to the final course seems a bit 'smoke and mirrors' to me.

What I find strange is that 2 highly experienced navigators couldn't work out the ships position after 4 hours (give or take) in a straight line from a known good fix. Conditions that night were pretty much perfect for taking fixes and for keeping on track. Clear skies, flat seas and light airs. The QM could hold the ship on course with the tips of his fingers.

Boxhall worked up the fix taken at around 19:30. All he needed to know was the speed of his ship and the course to know where they were at 23:40.

That's 4 hours and 10 minutes at, between 21 and 22 knots.

Captain Smith's position was about 20% too far and Boxhall's about 10%. Ships don't end up 20 and 13 miles from a known good fix in 4 hours unless someone screwed the maths.

Hello Rob

Rob, you are right! Two such men could perform such simple tasks standing on their heads. A Second Year Cadet or Midi could do the same thing. We are not considering professional incompetence.
Captain Smith used false information provided by A. N. Other. Boxhall obviously mis-judged the speed and used the wrong run-time.

By your "Smoke and Mirrors" observation are you suggesting "the obscuring or embellishing of the truth of a situation with misleading or irrelevant information."?

Nothing could be farther from the truth.

In fact, Titanic's behavior between Noon, April 14 and 5-50 pm that early evening, is the
lynch-pin of the clock alteration argument as well as the basis on which Boxhall built his distress position. Simply because it determines exactly where Titanic was when 2nd Officer Lightoller took his star sights and consequently established the exact position from which Boxhall worked his distress position. If that period in the short life of Titanic is glossed-over without proper examination, then we go on having this endless argument.

Aaron's current suggestion is a start.

Here is another question.

Q7: Was there any evidence to suggest that such a current existed? Might it be reasonable for an experienced officer to expect such a current and allow for it?
A7: Yes! The evidence of 5th Officer Lowe very clearly indicates a reduction in expected speed, which, if using propeller revolutions would be judged as 21.5 knots. Lowe very clearly quoted an average speed of 20.95 knots...0.55 knots slower than expected.

 

[Samuel Halpern]

What I find strange is that 2 highly experienced navigators couldn't work out the ships position after 4 hours (give or take) in a straight line from a known good fix.

Your right, and you answered how they screwed it up when you said: "Captain Smith's position was about 20% too far and Boxhall's about 10%. Ships don't end up 20 and 13 miles from a known good fix in 4 hours unless someone screwed the maths.."

 

[Samuel Halpern]

The Calculated distance to run from Daunt Rock departure to The Corner is exactly 1673 nautical miles. The distance is made-up of 55 miles from Daunt Rock to 1 mile south of the Fastnet Rock, then 1618 nautical miles on a Great Circle course to The Corner.

Absolutely! But to suggest that Titanic was tracking along the GC route perfectly is ludicrous, and you Jim of all people should know that. But don't take my word for it. Here are the travel distances of Olympic from Daunt Rock to the Corner for the first three westbound voyages in 1911 over same exact route: 1674,1676, 1677. In Feb 1912, it was 1675.

 

[Rob Lawes]

Him Jim

I understand the need to track back and review the ships course in the run up to the collision in order to attempt to reconstruct the events up to that point.

My point is that it is misleading and obscuring the truth when talking about the distress position in that the bridge crew wouldn't need to refer to the corner turn in order to calculate there final position.

The purpose of your and Sam's discussion is to retrace the steps taken. I completely understand why since the location of that 19:30 fix went to the grave of all concerned.

I still contend, as you also described, that the matter of working out the final position of the ship starting from the last know fix was absolute bread and butter for an experienced navigator. Therefore the size of the error is bizarre.

There may have been a current affecting the westerly progression of the ship, I don't know, but as you point out, that difference was .55 of a knot which over 4 hours equates to 2.2 miles. That still leaves Smith's position 17.8 miles out and Boxhall's 10.8. A statistically significant error.

 

[Samuel Halpern]

Here is a little thought to ponder. I believe, based on the 1549 miles run from Daunt's Rock to noon April 14th, Titanic was 126 miles from the Corner. The sum of those two distances equates to 1675 miles from Daunt Rock to the Corner, matching Olympic's Feb 1912 run. If you work out the distance of the Smith CQD, 41° 44'N, 50° 24'W, back to the Corner at 42°N, 47°W, you find a distance of 153 miles. Add the two and you get 126+153=279 miles from Noon to the Smith CQD. Now how long would it take for the ship to travel that distance at an average speed of 22 knots? 279/22=12.68 hours, or a smidge over 12 and 2/3 hours which is equal to 12 hours and 40 minutes. That is ONE hour greater than the 11 hours and 40 minutes from noon to when the ship struck the berg. To me, this suggests a simple mental error that resulted in a 1 hour overrun when it came time to work out the initial CQD position. Something easily done in the haste to work out a set of distress coordinates.

Well, enough speculation.

 

[Jim Currie]

Absolutely! But to suggest that Titanic was tracking along the GC route perfectly is ludicrous, and you Jim of all people should know that. But don't take my word for it. Here are the travel distances of Olympic from Daunt Rock to the Corner for the first three westbound voyages in 1911 over same exact route: 1674,1676, 1677. In Feb 1912, it was 1675.

Where did I ever suggest such nonsense? I showed that she was set to the southeast.

Captain Smith was in charge of Navigation. He would decide when to turn onto the next course. It is unlikely that he would share his thoughts with his lowly 4th officer. However, that same 4th Officer and likewise the 3rd Officer were in charge of routine navigation and needed DR positions to carry out that work. Since they would not have any idea what Smith had planned, they would simply follow his orders. They both would need to have dead reckoning positions for various duties. These would include DRs for 5-50 pm, for 6 pm, 7-30 pm evening sights and 8 pm
Until they obtained a fixed position, they would simply use the intended course from Noon to 5-50 pm then the intended course thereafter. Boxhall could not have known what course the ship was actually making until he worked the 7-30 pm sights. Then he simply used his 5-50 pm DR combined with the 7-30 pm fix position to obtain a course being made good from the turn position. But keep in mind, that was a DR position.
You will recall that he was of the opinion that Smith compensated for an overshoot of The Corner and instead of steering 265.5 True, was making 266 True.

 

[Jim Currie]

Him Jim

I understand the need to track back and review the ships course in the run up to the collision in order to attempt to reconstruct the events up to that point.

My point is that it is misleading and obscuring the truth when talking about the distress position in that the bridge crew wouldn't need to refer to the corner turn in order to calculate there final position.

The purpose of your and Sam's discussion is to retrace the steps taken. I completely understand why since the location of that 19:30 fix went to the grave of all concerned.

I still contend, as you also described, that the matter of working out the final position of the ship starting from the last know fix was absolute bread and butter for an experienced navigator. Therefore the size of the error is bizarre.

There may have been a current affecting the westerly progression of the ship, I don't know, but as you point out, that difference was .55 of a knot which over 4 hours equates to 2.2 miles. That still leaves Smith's position 17.8 miles out and Boxhall's 10.8. A statistically significant error.

Hello Rob.

It has all to do with runtime.

If there was a reduction in speed between Noon and 5-50 pm... and the evidence suggests there was, then the distance covered would be the same, but the time to cover it would be longer.

Everyone approaches this problem in the calm of their respective locations. Boxhall did not have that luxury. He was working under immense stress.

By the way, I'm sure you know that the equivalent RN name for "Midi" is "Snotty"

 

[Aaron_2016]

There may have been a current affecting the westerly progression of the ship, I don't know, but as you point out, that difference was .55 of a knot which over 4 hours equates to 2.2 miles. That still leaves Smith's position 17.8 miles out and Boxhall's 10.8. A statistically significant error.

Would be fascinated to learn if the survey ships had difficulties with the currents when they conducted the Titanic expeditions. I wonder if there were problems when the submersibles were exploring the wreck and the survey ships on the surface had to keep their own engines on slow ahead in order to fight the current and stay in position so that the submersibles could conduct their search without interference from the currents above?


The Titanic had the misfortune of steaming against the gulf stream below and the labrador current curling towards it from above.

I believe this affected the distance she covered and altered the atmosphere around the ship as she lay between two temperatures.

When the ship broke apart the middle section was carried a great distance with the currents towards the east. Heavy sections of the ship landed up to half a mile to the east practically in a straight line with the current. This could be a strong indication that the current was powerful because the middle section woud have sank in a short time, and yet it was scattered half a mile towards the east.

I recall several survivors who rowed a short distance away towards the east and they believed the explosions on the ship had caused their lifeboat to be pushed a great distance away from the ship as it went down. I believe it was simply the strong currents which had pulled their lifeboats far to the east. e.g. Lifeboat 11 was rowing towards the east, but they were overloaded with people and it was difficult to row away, however Edith Rosenbaum was in the lifeboat and she said:

"There was a very heavy explosion under water, a second and then a third. We were surprised that instead of sucking us in, the effect was to the contrary, it pushed us out and onward."

I believe it was most likely the strong currents that had pushed them out and onward towards the east and away from the ship. Back in the 1980's the original research teams that were out there trying to find the wreck believed the Titanic had drifted away up to 5 miles from her original distress position before she sank. They probably came up with the 5 miles drift because they had been in that region and felt the power of the currents affecting their survey ship.


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