Boxhall's CQD position


Rob Lawes

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I should know better than to address subjects about which I know nothing, but did Smith himself work out Titanic's position that night, or just Boxhall?
Boxhall spent the evening plotting the set of star sights taken by the 2nd Officer at around 19:30.

Smith worked up the initial distress position presumably based in part on the information provided by Boxhall and by dead reckoning.

Immediately after the first distress messages were transmitted Boxhall worked up a slightly more accurate position which was then provided to the Marconi room and transmitted in all subsequent messages.
 

Jim Currie

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Hi Jim,
What is wrong speculating on Murdoch mind? After all there is lots more speculating of the Titanic last movements as the log book and chart maps are all loss with the ship, making a difficult task to sort out and trying put together what exactly happened that night and probably never ever know 100% for sure. Speculation indeed!
I am trying to understand why such an experience captain as Smith has got the navigation position wrong followed by Boxhall too?
I just get the feeling Murdoch knew (speculation if you like) there was some was just quite right by smell the ice comes to mind! But he was stuck in that position having to carry out the Captain order. Come to think about it why hasn't Murdoch work out the position too?
Hello Mike.

There is absolutely nothing wrong with speculating about an historical event, if the result of such speculation begins with "What if?"
The problem on this site and many others is that Eurika! and "Ah! That's what happened then." moments, are often developed into historical fact.

If you understand what was going on at a moment in time or can clearly visualize a description of what was going on at that time, then there is no need for speculation. Suitably qualified individuals more easily visualise missing connections.
For example...following a great flood, road re-construction teams can easily visualise a missing bridge.:rolleyes:

Technical re-construction of the evidence given by Boxhall and Smith shows that Smith was simply fed improper data and Boxhall made the wrong assumptions regarding speed and steaming time.
However, these reasons will not be accepted by those who revel in conspiracy theories or who start with an answer, work backward and while doing so, reject important evidence which does not fit.
Why should we be surprised at such an approach, when professionals in the shape of Captain Knapp USN and Captain Rostron of the Carpathia blatantly bent the truth to suit the occasion.
 

Jim Currie

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Boxhall spent the evening plotting the set of star sights taken by the 2nd Officer at around 19:30.

Smith worked up the initial distress position presumably based in part on the information provided by Boxhall and by dead reckoning.

Immediately after the first distress messages were transmitted Boxhall worked up a slightly more accurate position which was then provided to the Marconi room and transmitted in all subsequent messages.
Small correction:
According to Boxhall, Smith used the 8pm DR position as the starting point to calculate his distress position. Also, according to Boxhall, that 8 pm Position was 20 miles out.
The 8 pm DR position was calculated by 5th Officer Lowe. To do so, Lowe would have used 3rd Officer Pitman's DR for use with Lightoller's sights
Coincidentally, Captain Smith's distress position is also 20 miles out. Admittedly in the wrong direction from that given in Boxhall's 1962 BBC interview, but 20 miles never-the-less.
In fact, Boxhall had nothing to do with the 8pm DR and no reason to consult it at any time.
 

Mike Spooner

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I should know better than to address subjects about which I know nothing, but did Smith himself work out Titanic's position that night, or just Boxhall?
Hi Mark,
I would agree with you a person like me who is not a navigation and looking into as an outsider point of view.
I have now had the time to read Jim Currie article: Re-Opening Can of Worms. First I do respect Jim as a experience professional seaman and contributed an enormous amount into ET. My personal congratulation to him.
Reading his article I am quite shock to see so many officers and captain are making mistakes after leaving Queenstown. I am thinking this is the cream of the crop officers and yet Atlantic crossings are nothing new to them either.
So I am going back to the navigation equipment and was it giving correct reading at the time? If not it doesn't how many times Boxhall recalculate the position he will get it wrong.
Now with your little help from you experience seamen. If the ship leaves Belfast, Southampton, Cherbourg and on to Queenstown. Would I be right to say like land references: Hill tops, Lighthouses and buildings are a good guide for navigation? As at this stage things like compass, chromite clock, sexton, RPM, stars and sun etc are not the bees knees for dead accuracy.
However when leaving Queenstown you are now on your own in the Atlantic with no land reference as guidance were now the dead accuracy of navigation equipment is required? True or false!
 
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Dead reckoning is just a method of recording a ship's movements between fixes using its "run" from the starting fix. The "run" i was calculated on duration (aka "time"), speed, and direction. In 1912 the process was done using the methods of traverse sailing which originated as ships began making extended offshore voyages. The instruments necessary for dead reckoning were something to measure speed (taffrail log) an ordinary clock, and mariner's compass. The compasses in Titanic could be read to 1/2-degree accuracy.

Pencil and paper were also needed. Data recorded during the run would be combined mathematically into a lat/lon position.

It was never intended for dead reckoning to be perfectly accurate. The DR is expected to be "off" compared to a fix taken for the same moment in time. This is not an error as such, but rather the inevitable result of wind and current. Comparison of the fix to the DR allows the navigator to determine the set and drift caused by these natural forces.

A "fix" is a lat/lon position based on either observation of fixed objects ashore (best) or on stellar observations at sea (less accurate). A minimum of two observations of fixed objects and three is considered the "gold standard." each observation produces a line of position, or LOP, based on the true compass direction from the ship to the object. These lines of position are plotted on a chart, the ship's position is taken as where they cross. Or, more likely inside the small triangle (called a "cocked hat") produced by their crossing.

Even though highly useful, fixes were not perfectly accurate. For instance, assuming it took the navigator of Titanic 6 minutes to obtain the bearings or celestial observations for a fix. At 22 knots this would mean that the first bearing was taken 2.2 nautical miles from the last one. (6 minutes= 1/10th hour X 22 knots = 2.2 miles run.) American navigators learned to apply a bit of "Kentucky windage" to their work in an effort to compensate for this time distortion effect.

-- David G. Brown
 
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American navigators learned to apply a bit of "Kentucky windage" to their work in an effort to compensate for this time distortion effect.
Sights were taken over a period of about 10 minutes, and the exact time of each site was recorded. Each line of position was adjusted by the speed and direction of ship movement so that they all would corresponded to the same exact time, usually the time of the very last sight taken. Over ten minutes, any error in speed or course angle in these adjustments would be essentially insignificant compared to other errors in measurement. A fix obtained would usually be good to within about a nautical mile barring no errors in the calculations or a systematic error in measurement.
 

Jim Currie

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Sights were taken over a period of about 10 minutes, and the exact time of each site was recorded. Each line of position was adjusted by the speed and direction of ship movement so that they all would corresponded to the same exact time, usually the time of the very last sight taken. Over ten minutes, any error in speed or course angle in these adjustments would be essentially insignificant compared to other errors in measurement. A fix obtained would usually be good to within about a nautical mile barring no errors in the calculations or a systematic error in measurement.
These 6 sights would have been completed by Lightoller in 5 minutes or less A great deal of preparation would have been made by Pitman, long before Lightoller appeared on the bridge after dinner.
Pitman would have calculated the time at or near the meridian of three stars. these would be used to obtain Latitude by Meridian Altitude. He would also select 3 other stars to be worked as Longitudes
Before Lightoller appeared on Deck, Pitman would have prepared a sights sheet. On it, in pairs, would be the names of the celestial bodies to be measured as well as their approximate sextant altitudes of each.
The stars used would already be well known to Lightoller and he would know that they were on the Meridian about 4 minutes earlier each day
When he arrived on the bridge, he would set his sextant to the approximate altitude of the first body. When ready, Pitman would be stationed over the chronometer box with pencil at the ready. Lightoller would measure the first altitude with his sextant and shout "Time" at the appropriate moment. Pitman would note the time on his sheet. Thereafter, Lightoller would reset his chronometer, take the sights in pairs and in order and shout "Time" as each body was brought to the horizon. The whole operation would take less than 5 minutes. More so since the weather was text-book perfect for taking sights.
At the end of it all, Boxhall and Pitman would have calculated between them 3 latitude position lines and 3 longitude position lines.
Since the course was almost westerly, an error in latitude would be instantly obvious.
Boxhall believed that Titanic was making less than 22 knots at that time, therefore, her westerly longitude was changing at the rate of about 1.5 minutes every 3 minutes. This means that there would be a maximum difference of longitude of about 2.5 minutes or 1.68 miles.
It is quite possible that when he was happy with the results...that they crossed checked OK,...Boxhall would have used the middle set of sights. to obtain the fix position of the ship at that time. That would be the position and GMT to be used when calculating subsequent DR positions until the next fix could be obtained.
 

Mike Spooner

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Why are you shocked? They were human beings, and they made mistakes, especially when under the pressure of a ship sinking beneath them.
Sam,
They are making mistakes before the thought of a sinking ship. Which I am trying to get the bottom of the matter why? This are very experience officers and the Atlantic is nothing new to them. Now I may trying to bit too precise of a ship position in those days, and it was only approximate position by what margin I don't know?
 

Georges Guay

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Robert Duane Ballard, a US Navy officer and professor of oceanography at the University of Rhode Island, discovered in the early morning hours of September 1st,1985, the RMS TITANIC wreck. The most probable position where the liner sank was given as 41°43.5’N / 049°56.8’W. Titanic enthusiasts jumped on the occasion to compare the wreck position against Smith and Boxhall CQD’s. It was found that the former distress position was 20 nautical and the latter 13 miles, both further to the west. Boxhall 41°46’N / 050°14’W CQD is recognized to be the official distress position.

Since 1985, every enthusiast tried to explain how a 13 miles offset could have happened. However, deducing 13 miles offset from the CQD against the Wreck position is at the source an incorrect navigation and shiphandling principle. It is absolutely impossible that at the time of collision, the liner was brought dead stop in split seconds, in still ocean waters and iceberg right by her side so to rest at exact wreck position. At the time of collision, the vessel was further east and south due to set & drift meaning that the erroneous distance was even greater!

Everybody saw in the movie Smith rushing in the navigation bridge. After hearing what Murdoch had to say, he ordered to close the watertight doors and the engines all stop (which was already done in real life), then he ordered finding the carpenter to sound the vessel. There is something missing here; the captain should then have told the mate that he was taking over command. The mate would then have notified him that the engines were ordered all stop, the elm hard over to port, the vessel swinging to starboard and there was nothing in sight.

The captain would then make sure the berg was clear before ordering the elm amidship. Later, we have testimonies that the commodore clutched the engines astern and then ahead followed by stop for good. That was a very audacious for not saying a reckless maneuver to fiddle about the engines after hitting ice in open waters. A damaged or loosen propeller(s) blade(s) could have been propelled against the hull and or a shaft been misaligned making the stern tube via the stuffing box, to both ingress more water. At least, the engine settings were slow and for a short period of time to the extent that the liner drifted mostly dead on her own inertia for a minimum of 15 minutes.

In the very best conditions, a fully standing by engine crew would crash stop the lightship giant in over half a nautical mile while being beaten up by enormous vibrations. That never happened. Titanic colliding at 22½ knots was developing 2 billion ft/lbs kinetic energy! According to Samuel studies, the titan went from 38 ft/s (22½ knots) at elm amidship, to 35 ft/sec (20¾ knots) at elm hard over and then to 34.5 ft/sec (20½ knots) after impact.

In 2013, A New Method for Accurate Prediction of Ship’s Inertial Stopping Distance calculated by the ALE (Arbitrary Lagrangian Eulerian) algorithm was elaborated. When compared with shipbuilders’ experimental basin data, the results calculated by ALE algorithm reach a precision of 98% while the results calculated by Captain Topley empirical formula (1988) reach a relative precision of 90.4%. Here is the formula:

1586787734766.png

SJ = The inertial stopping distance
v1 = The ship’s speed at dead stop or dropping anchor
v0 = The ship’s initial speed at stopping
C = The time halved constant of ship’s speed and can be calculated or interpolated from Table 1.

1586787781576.png

If we use 20½k as v0 for the ship’s speed after impact, 0.2k as v1 for the ship’s speed at dead stop and 9.8 as C interpolated from table 1 for Titanic deadweight, we found that SJ (the inertial stopping distance) equates 4.95 nautical miles.

If we then use Captain Topley empirical formula with the same data to corroborate ALE algorithm, while taking advantage of inserting the time it took for Titanic to stop as witnessed (11:45pm – 12:00pm), we found that SJ equates 5.0 nautical miles within a ¼ of an hour.

1586787821682.png


If we draw the result neatly on a nautical chart, making the vessel turning more rapidly at first to then equilibrate her lateral pressure forces and finally stabilize on a North heading by compass, the distance found from the wreck is 15.8 nautical miles, not the celebrated 13 nautical miles.

1586787864418.png

As I was reading Samuel’s book, I came across and froze to that sentence;
Senator SMITH; Mr. Boxhall, you seem to be the one upon whom we must rely to give the difference between ship's time and New York time; or, rather, to give ship's time and give the New York time when this accident occurred.
Mr. BOXHALL; At 11.46 p.m., ship's time, it was 10.13 Washington time, or New York time.


That very single reply is a very significant and reveling phrase! Like Samuel stated, it certainly played a role in the CQD miscalculations, since at 11.46p.m., ship's time, it was not 10:13pm New York time, but 09:44pm! Let’s see what I come up with…

«At 11.46 p.m., ship's time, it was 10.13 p.m. New York time»

In modern notation, at 23:46 LAT it was 22:13 NYT. Thence, 23:46 LAT – 22:13 NYT = 01h33 time difference between the liner and New York or 03h27 between the liner and Greenwich or 05h00 between New York and Greenwich.

When Boxhall made is famous calculations to deduce the CQD position, he used 23:46 LAT for the collision, 22:36 GMT as noted in his Celestial Navigation Logbook for the evening celestial fix and a speed of 22 knots.

1. Boxhaul Calculated Distance Run:
Collision Time:
23:46 LAT = 22:13 NYT
23:46 LAT – 22:13 NYT = 01h33
05h00 – 01h33 = 03h27 GMT

Running Time between the 22:36 GMT celestial fix and 03:27 GMT collision time:
[(24:00 – 22:36) + (03:27)] = 04h51

Distance Run:
04h51 x 22 knots = 106.7 nautical miles

2. True Distance Run:
23:46 – 02h02 = 21:44 NYT
23:46 + 02h58 = 02:44 GMT

Time elapsed between 23:46 LAT and 22:36 GMT celestial fix:
23:46 + 02h58 = 02:44 GMT
[(24:00 - 22:36) + 02:44] = 04h08

Distance Run:
04h08 x 22 knots = 90.9 nautical miles

Difference:
Boxhall 106.7 miscalculated miles - 90.9 true miles = 15.8 nautical miles

As I said previously; «If we draw the inertia stopping distance on a nautical chart, Boxhall CQD distance found from the wreck is 15.8 nautical miles.». Strange coincidence isn’t it?

Notes:

Astern power equates 40% Ahead power

Thomas P. Dillon;
engines brought to stop 1½ minute after impact
engines stop for ½ minute
engines brought to Slow Astern for 2 minutes
engines stop
engines brought Ahead for 2 minutes
engines Stop for good

Engines brought Ahead for 2 minutes supersedes engines brought Slow Astern for 2 minutes.

Case 2. Frederick Scott:
engines brought to stop 1½ minute after impact
engines brought Astern for 5 minutes
engines Stop
engines brought Slow Ahead for 10 minutes
engines Stop for good

Engines brought Slow Ahead for 10 minutes supersedes engines brought Astern for 5 minutes.

Thence, the liner drifted mostly dead on her own inertia...
 

Georges Guay

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Thank you Samuel but honestly, without your book(s) data I would never have been able to expose such an analysis! Thanks to you then … ;)
 
Last edited:

Georges Guay

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Smith Calculated Distance Run:

Collision Time:
23:46 LAT = 22:13 NYT
NYT + 05h00 = GMT
22:13 + 05h00 = 03:13 GMT

Time elapsed between 23:46 LAT and 03:13 GMT:
[(24:00 - 23:46) + (03:13)] = 03:27

Running Time between 22:36 and 03:27:
23:46 + 03:27 = 03:41 GMT
[(24:00 - 22:46) + (03:41)] = 05h05

Distance Run:
05h05 x 22 knots = 111.8 nautical miles

True Distance Run:
23:46 – 02h02 = 21:44 NYT
23:46 + 02h58 = 02:44 GMT

Time elapsed between 23:46 LAT and 22:36 GMT:
23:46 + 02h58 = 02:44 GMT
19:38 + 02h58 = 22:36 GMT
(24:00 - 22:36) + 02:44 = 04h08

Distance Run:
04h08 x 22 knots = 90.9 nautical miles

Difference:

Smith; 111.8 calculated miles - 90.9 true miles = 20.9 nautical miles :oops:
 

Alex Clark

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Robert Duane Ballard, a US Navy officer and professor of oceanography at the University of Rhode Island, discovered in the early morning hours of September 1st,1985, the RMS TITANIC wreck. The most probable position where the liner sank was given as 41°43.5’N / 049°56.8’W. Titanic enthusiasts jumped on the occasion to compare the wreck position against Smith and Boxhall CQD’s. It was found that the former distress position was 20 nautical and the latter 13 miles, both further to the west. Boxhall 41°46’N / 050°14’W CQD is recognized to be the official distress position.

Since 1985, every enthusiast tried to explain how a 13 miles offset could have happened. However, deducing 13 miles offset from the CQD against the Wreck position is at the source an incorrect navigation and shiphandling principle. It is absolutely impossible that at the time of collision, the liner was brought dead stop in split seconds, in still ocean waters and iceberg right by her side so to rest at exact wreck position. At the time of collision, the vessel was further east and south due to set & drift meaning that the erroneous distance was even greater!

Everybody saw in the movie Smith rushing in the navigation bridge. After hearing what Murdoch had to say, he ordered to close the watertight doors and the engines all stop (which was already done in real life), then he ordered finding the carpenter to sound the vessel. There is something missing here; the captain should then have told the mate that he was taking over command. The mate would then have notified him that the engines were ordered all stop, the elm hard over to port, the vessel swinging to starboard and there was nothing in sight.

The captain would then make sure the berg was clear before ordering the elm amidship. Later, we have testimonies that the commodore clutched the engines astern and then ahead followed by stop for good. That was a very audacious for not saying a reckless maneuver to fiddle about the engines after hitting ice in open waters. A damaged or loosen propeller(s) blade(s) could have been propelled against the hull and or a shaft been misaligned making the stern tube via the stuffing box, to both ingress more water. At least, the engine settings were slow and for a short period of time to the extent that the liner drifted mostly dead on her own inertia for a minimum of 15 minutes.

In the very best conditions, a fully standing by engine crew would crash stop the lightship giant in over half a nautical mile while being beaten up by enormous vibrations. That never happened. Titanic colliding at 22½ knots was developing 2 billion ft/lbs kinetic energy! According to Samuel studies, the titan went from 38 ft/s (22½ knots) at elm amidship, to 35 ft/sec (20¾ knots) at elm hard over and then to 34.5 ft/sec (20½ knots) after impact.

In 2013, A New Method for Accurate Prediction of Ship’s Inertial Stopping Distance calculated by the ALE (Arbitrary Lagrangian Eulerian) algorithm was elaborated. When compared with shipbuilders’ experimental basin data, the results calculated by ALE algorithm reach a precision of 98% while the results calculated by Captain Topley empirical formula (1988) reach a relative precision of 90.4%. Here is the formula:

View attachment 48362
SJ = The inertial stopping distance
v1 = The ship’s speed at dead stop or dropping anchor
v0 = The ship’s initial speed at stopping
C = The time halved constant of ship’s speed and can be calculated or interpolated from Table 1.

View attachment 48363
If we use 20½k as v0 for the ship’s speed after impact, 0.2k as v1 for the ship’s speed at dead stop and 9.8 as C interpolated from table 1 for Titanic deadweight, we found that SJ (the inertial stopping distance) equates 4.95 nautical miles.

If we then use Captain Topley empirical formula with the same data to corroborate ALE algorithm, while taking advantage of inserting the time it took for Titanic to stop as witnessed (11:45pm – 12:00pm), we found that SJ equates 5.0 nautical miles within a ¼ of an hour.

View attachment 48364

If we draw the result neatly on a nautical chart, making the vessel turning more rapidly at first to then equilibrate her lateral pressure forces and finally stabilize on a North heading by compass, the distance found from the wreck is 15.8 nautical miles, not the celebrated 13 nautical miles.

View attachment 48365
As I was reading Samuel’s book, I came across and froze to that sentence;
Senator SMITH; Mr. Boxhall, you seem to be the one upon whom we must rely to give the difference between ship's time and New York time; or, rather, to give ship's time and give the New York time when this accident occurred.
Mr. BOXHALL; At 11.46 p.m., ship's time, it was 10.13 Washington time, or New York time.


That very single reply is a very significant and reveling phrase! Like Samuel stated, it certainly played a role in the CQD miscalculations, since at 11.46p.m., ship's time, it was not 10:13pm New York time, but 09:44pm! Let’s see what I come up with…

«At 11.46 p.m., ship's time, it was 10.13 p.m. New York time»

In modern notation, at 23:46 LAT it was 22:13 NYT. Thence, 23:46 LAT – 22:13 NYT = 01h33 time difference between the liner and New York or 03h27 between the liner and Greenwich or 05h00 between New York and Greenwich.

When Boxhall made is famous calculations to deduce the CQD position, he used 23:46 LAT for the collision, 22:36 GMT as noted in his Celestial Navigation Logbook for the evening celestial fix and a speed of 22 knots.

1. Boxhaul Calculated Distance Run:
Collision Time:
23:46 LAT = 22:13 NYT
23:46 LAT – 22:13 NYT = 01h33
05h00 – 01h33 = 03h27 GMT

Running Time between the 22:36 GMT celestial fix and 03:27 GMT collision time:
[(24:00 – 22:36) + (03:27)] = 04h51

Distance Run:
04h51 x 22 knots = 106.7 nautical miles

2. True Distance Run:
23:46 – 02h02 = 21:44 NYT
23:46 + 02h58 = 02:44 GMT

Time elapsed between 23:46 LAT and 22:36 GMT celestial fix:
23:46 + 02h58 = 02:44 GMT
[(24:00 - 22:36) + 02:44] = 04h08

Distance Run:
04h08 x 22 knots = 90.9 nautical miles

Difference:
Boxhall 106.7 miscalculated miles - 90.9 true miles = 15.8 nautical miles

As I said previously; «If we draw the inertia stopping distance on a nautical chart, Boxhall CQD distance found from the wreck is 15.8 nautical miles.». Strange coincidence isn’t it?

Notes:

Astern power equates 40% Ahead power

Thomas P. Dillon;
engines brought to stop 1½ minute after impact
engines stop for ½ minute
engines brought to Slow Astern for 2 minutes
engines stop
engines brought Ahead for 2 minutes
engines Stop for good

Engines brought Ahead for 2 minutes supersedes engines brought Slow Astern for 2 minutes.

Case 2. Frederick Scott:
engines brought to stop 1½ minute after impact
engines brought Astern for 5 minutes
engines Stop
engines brought Slow Ahead for 10 minutes
engines Stop for good

Engines brought Slow Ahead for 10 minutes supersedes engines brought Astern for 5 minutes.

Thence, the liner drifted mostly dead on her own inertia...
Georges, im just getting my head around all the figures, is the suggestion that Boxhall position for the collision was perhaps closer to the mark but that the ship drifted to the wreck position afterwards, hence the seeming inaccuracy in Boxhall’s CQD position?
 

Jim Currie

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There is no evidence to show that a second helm engine order was given as part of the berg avoidance tactic. To be effective such an order would have to have been given immediately. In fact. the helmsman was pointedly asked about that and was very positive in his answer. I quote:

1314. You were given the order to hard-a-starboard? A: - Yes.
1315. Was that the only order you had as to the helm? A: - Yes.

A second helm order was given... but much later... when the iceberg was astern. This second order has been stretched by researchers to include Murdoch's attempt to clear the berg. However, an experienced officer like Murdoch would know that to be effective if at all, it would need to have been given as part of a flowing sequence of events.
 

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