Two Points in Thirty-Seven Seconds

Mar 22, 2003
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A new article of mine dealing with the turning characteristics of Olympic and Titanic was posted in PDF format on the Titanic Research & Modeling Association (TRMA) website. It is called: She Turned Two Points in 37 Seconds. Based on data presented by H&W's naval architect Edward Wilding, we were able to recreate the turning circle of these ships with the helm put hard over at full speed ahead. We also were able to determine the performance during several zig-zag maneuvers where the helm is ordered shifted to the opposite side at a specified time following an initial helm order.

We also looked at the classic story of Titanic’s encounter with the iceberg and found that some of the conclusions in the British Wreck Commission report were not entirely consistent with information given by both lookout Frederick Fleet and QM Robert Hichens. We also show that QM Hichens’ claim that the ship had turned two points just as she struck the iceberg is inconsistent with his claim that he just managed to get the wheel hard over just as she struck. We also considered the claims of Fourth Officer Joseph Boxhall and QM Alfred Olliver, and how they fit into the overall picture.

We also looked into the dynamics of the initial impact with the iceberg and quantified the initial loss of energy that resulted from damage to the ship's structure. Furthermore, we showed that once the ship’s underwater hull form widened out to the full breadth of the ship, any remaining side contact with the iceberg would not be enough to cause any deformity in the shell plate, but would allow ice to be deposited through open port holes and onto windows as was observed in different parts of the ship.

Several appendices are included with show the details behind the various curves and data that is presented. Included in the appendices are the estimated hydrodynamic force acting on the ship's rudder when put hard over at full speed, the angle of heal of the ship during a full speed turn with hard over helm, the loss of speed due to added hydrodynamic drag as a function of drift angle during a turn, and what would be the expected force of the berg against the ship's side assuming the rudder is kept in a position to keep ship's hull pinned against the berg during an allision event.

Despite the length and technical detail of this article, I hope you will find the information that is presented to be interesting and informative.
 

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Tad G. Fitch

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This is a really good article Sam, and very well-written. I found the discussion about what really transpired prior to the collision particularly interesting.
 

Jim Currie

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Well done Sam! Excellent presentation and a great deal to think about.

I have one or two comments:

I note all the work on the turning circle and zig-zag is based on the vessel with her engines running on full ahead.

There is so much to take in that I probably missed not a few things.

As you know, the pivot point moves about according to the applied forces. I note you place it somewhere aft of the C.of G. after the impact. I also assume you know that the Centre of Lateral Resistance can be as much as 10% forward of the C.0f G.on a fast ship. Probably about 350 feet from the bow. This being so, the impact of ice would impose a force against the ship's side - similar to that of a tug pushing in that area. Hence the subsequent movement of the pivot point from it approximate position 0.3L from the bow to about 0.25L from the stern.
Since the force against the rudder would have been considerably diminished by that time (Engines stopped) - and the impact point was getting near to the C.of L.R.- I wondered if you had considered side-ways displacement?

You are obviously still sold on the Zig-Zag theory. As you've told me "you're entitled to you opinion". I would however take issue with a few of your assumptions.

First, I note you are now thinking that the Zig was emergency and the Zag was precautionary.

The second observation concern the 'meat' of your article.

Hitchens's 2 points in 10 seconds is of course a farce. However, I cannot see any reason to doubt the ship's head moved 2 points before the impact. Forget the timing, he didn't have a stop watch - just a compass which showed that the ship's head had swung about 23 degrees from her original heading at the moment of impact. As you point out in your article - he claimed that was what happened in his original statement in any case.

You mention Boxhall and Oliver as witnesses. That's a strange pair!

Boxhall stated he was just about at the Captains accommodation (60 feet?) from the bridge at time of impact. While olliver stated he was just at the bridge at that exact same time. This means Boxhall was about 50 or 60 feet behind him.
Both men said they heard the lookout bells but onl;y the one farthest from the bridge heard the shouted hard-a-starboard order and the ringing of the engine telegraph. The farthest away man did not see the berg as it passed the bridge wing although he was less that 20 feet from it while the other did see it as it passed the bridge wing.
Both men saw Murdoch at the WT door handle.
This is not just simple absent mindedness. Someone was telling 'porkies' as they say.
If Boxhall was 50 feet behind Olliver - no matter what side of the bridge the latter was on, then Olliver must have heard exactly the same thing as Boxhall.

Boxhall's timing is not too exact either but then he did not have a particular reference for time - Olliver did; he was just finishing his work at the compass when he heard the bells. You have established it would have taken him about 55 seconds to reach the bridge from his post at the standard compass therefore there was a 55 second interval between bells and impact.
Since the builders said it took 37 seconds to make the turn of 2 points, it follows that if Olliver's timing is correct then there was an interval of between 13 and 15 seconds from the last bell of the three untill the order of hard-a-starboard was given. This seems about right and the ice was nearer to 1800 feet ahead of Titanic when the lookouts first saw it.

You mention about the apparent alteration of heading as seen by the lookouts. This was a relevant measurement and these guys did have a point of relevance - the iceberg.

You also mention that a witness saw the berg on the starboard quarter when the ship was almost stopped.

I notice you also used Boxhall's UK evidence as to what Murdoch told Smith rather than the US version. In the first version Boxhall has Murdoch telling Smith that he was attempting to 'port round it' i.e. avoid it by going to port. The second version has the 'hard-a-' bit in it. But even in the second version, Boxhall has Murdoch saying he was 'going' to hard-a-port round it. Murdoch did not say that he did do so or had even started to do so!

Got to go now but I would be interested to know when the witness saw Titanic almost stopped with the berg on her starboard quarter, There is only two positions where that could happen. The first one would be south and ahead of the berg and the other to the north west of it. Considering the second point is near to 4000 feet away while the first is less than half that, I would be betting the first point was where she was when she was almost at a stand still. She was only moving at a little over quarter sped 2 minutes after impact according to Lightholler and the engines were stopped at that time.

I really did enjoy your work and ceratinly found no fault with the rechnicalities.

Happy New Year,

Jim
 
Mar 22, 2003
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Hello Jim and happy new year to you and to everyone.

>>I have one or two comments<<

Just one or two? You never have just one or two.
happy.gif


>>I note all the work on the turning circle and zig-zag is based on the vessel with her engines running on full ahead. <<

Yes, that is correct. The rationale is that the evidence shows that whatever engine orders Murdoch may have sent down, there just was not enough time for them to be carried out before the ship struck the ice. As I pointing out in the article, most witnesses said the engines came to a stop about one to two minutes after the collision event. Even Lightoller noticed that, as well as quite a few others. The evidence also suggests that the engines were backed briefly after they first came to a stop to take the way off the ship. But again this was about two minutes after the collision.

>>I wondered if you had considered side-ways displacement? <<

Yes, the collision analysis that I talk about (App. G) showed that a sway velocity component of 1.4 ft/sec would have been introduced by the impact plus an added yaw component of 1 degree per sec. The analysis assumed a iceberg of infinite mass to keep things simple. So I think these numbers are really upper bounds. As you know, a ship has the greatest resistance in the lateral direction, and added sway movement without a force to sustain it would be dampened out relatively quickly.

>>I note you are now thinking that the Zig was emergency and the Zag was precautionary.<<

I think I've been saying that all along. The first order was an attempt to avoid a collision. The second, which took place after the collision, in my opinion was to minimize further damage as the berg was passing aft. As I said in that other thread, I cannot believe a ship handler would not try to swing the stern away from an object that was in contact with the ship's side.

I know that you have suggested that the hard-aport order was done much later to bring the ship back on course when the order was given to to move the ship ahead again briefly. I don't believe that for two reasons. One, is that the helm order was given by Murdoch, but it was Smith who was seen to have rung down 1/2 ahead on the telegraph when the ship was moved ahead again. I believe Smith would would be the one to give both orders if that is what they were trying to do. If Smith left it to Murdoch to give those orders, then it would be Murdoch on the telegraph, not Smith as was witnessed. Secondly, putting the ship's head back on her course heading to NY seems to me like the last thing to worry about after colliding with an iceberg, especially without knowing what the full extent of damage was. Also, the movement of the ship ahead again through the water was witnessed about the time they started to uncover the boats (Beesley).

>>Hitchens's 2 points in 10 seconds is of course a farce. However, I cannot see any reason to doubt the ship's head moved 2 points before the impact.<<

If Hichens was wrong about striking the berg as soon as he got the helm over hard, then why do you think he was right about the ship turning 2 points just before she struck? That is why I compared what he said to what Fleet said. I agree that Hichens had the compass in front of him. I also agree he saw the ship swing about 2 points off her course heading. What I don't agree with is that the two-point swing happened entirely before first contact with the ice.

>>You mention Boxhall and Oliver as witnesses. That's a strange pair! <<

Why a strange pair? You are not suggesting that one is more reliable over the other, are you?

>>Boxhall stated he was just about at the Captains accommodation (60 feet?) from the bridge at time of impact. While olliver stated he was just at the bridge at that exact same time. This means Boxhall was about 50 or 60 feet behind him. <<

Actually, Boxhall was very specific as to where he allegedly was when he heard the lookout bells. He said was coming out of the officers quarters (15344) which is only about 60 ft from the bridge. He also said he was almost on the bridge when the ship struck (15349). His timing suggests about 15 seconds between the three bell warning and the collision. He presents a very accelerated time frame, and I have to question what exactly did he really witness, and that includes the minute or two after walked onto the bridge.

>> it follows that if Olliver's timing is correct then there was an interval of between 13 and 15 seconds from the last bell of the three untill the order of hard-a-starboard was given.<<

That assumes that about 37-40 seconds went by from the hard-astarboard order to when the ship struck. Hichens said it was about 1/2 minute between the three bells and when the order was given. Fleet said he was at the phone for about 1/2 minutes after striking three bells, and first noticed the ship starting to veer to port after he left the phone. That would make it about 20 seconds for the ship to turn before striking, and that puts the berg over slightly to starboard of the centerline as Fleet sketched it when first seen. It could be that somewhere in between 15 to 30 seconds went by before the order was given, which would put the berg almost dead ahead when first seen. But why would Murdock wait any longer than the time it would take him to see that and react before ordering the helm over?

>>You also mention that a witness saw the berg on the starboard quarter when the ship was almost stopped. <<

I believe I said there were a number witnesses who said they saw the berg disappearing off the starboard quarter following the collision as the ship was coming to a stop.

>>I notice you also used Boxhall's UK evidence as to what Murdoch told Smith rather than the US version...Murdoch did not say that he did do so or had even started to do so! <<

Yes, that is correct. In the US he said: "I intended to port around it...But she hit before I could do any more." In the UK he said: "I was going to hard-a-port round it but she was too close." To me, he was saying the same thing but using different words. Of course we only have Boxhall for this information as to Murdoch's intent. Neither Olliver nor Hichens say anything about this, let alone that Murdoch told Smith that he ordered full speed astern as Boxhall also claimed.

On a completely separate issue. Why, in your opinion, was Moody stationed in the wheelhouse at night leaving Murdoch alone to keep lookout by himself out on the bridge? Other than keeping an eye from time to time that the QM was holding to the course written on the course board, or when they had to do a compass check, what does keeping a J/O in the wheelhouse accomplish, especially since they expected to be coming up to the ice at any moment?
 

Jim Currie

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Good morning Sam!

In biblical terms: 'the last shall be first'.

I have no idea what was in the wheelhouse of Titanic but using that awful word 'experience' : as a a junior officer in exactly the same position as was Moody: I would do exactly as you described with perhaps a few extra chores depending on how the particular ship was run.

Arriving or leaving port, Moody's post would be as Hichens described it - abaft the helmsman, seeing every order was carried out to the letter.
In the case of ice and/or poor visibility, Moody would be stationed on one side of the bridge and his watch boss on the other. From time to time, Moody would leave his post to carry out essential routine chores. One of which was to answer the bridge telephones. My guess is he did exactly that and thereafter stayed beside the helmsman throughout the emergency.

You will recall that a minute or so after the impact, Murdoch was seen on the port wing of the bridge and Smith on the starboard side. At that time, Moody would still be in the wheelhouse with Hitchens.
Olliver, as testified by Hitchens, was by then back at his post at the rear bulkhead of the wheelhouse). This suggests that the ship was still going ahead, but as Lightholler said - very slowly.

My observation about the ship coming to a halt with the berg on the starboard quarter, points-out that the berg's relative bearing at that time was somewhere about 45 degrees to the right of astern when Titanic was almost stopped. Using your own turning diagram, this means that Titanic was either heading north or west at that time.
Still using your diagram; the berg was therefore about 4000 feet or 2000 feet away from the ship at that time depending on how she was heading.
All of the witnesses to seeing the berg had emerged from brightly lit accommodation. All were looking toward the berg through the side-glare of the ship's starboard side. If the lookouts, with perfect night sight, who were trained to do so could not see the berg much more than 2000 feet ahead, how on earth did all these folks see it under the conditions I have just described? Remember, Boxhall stated in all honesty he was not sure of seeing it and his night vision had probably been 75% restored.
I don't think those witnesses could have seen the berg at a distance of more than half a ships length astern of Titanic. i.e. little more than 1000 feet from where they were standing at the time on the ship's forward well deck.


There was only two ways to find out what the initial engine order was - by actually hearing it or by seeing the pointer on the telegraph dial.
On a ship, unless the senior Officer of the Watch or Commander gives a subordinate an engine order, such an order will not be heard by anyone.
The senior man will ring the telegraph himself.
In the case of Murdoch's emergency; he would ring 'stop' then 'full astern'. If the control platform lads in the engine room were handy at the time, the bridge order would be acknowledged immediately. Thus the double order of 'stop' then 'full astern' would be almost simultaneous.

When Boxhall looked at the illuminated dial on the telegraph, he would see the arrow on one side pointing to 'full astern'. At that moment, the steam to the engines would have been shut-off and the pistons slowing down rapidly. There would be no cavitation vibration until the engines actually started turning the props in reverse.

I am not surprised that neither Hichens of Olliver did not know how the engines were operating during the initial phase.
However, I am absolutely sure that there would be only two times when Captain Smith would lay hands on the telegraph and give a direct order to the helmsman: one would be in a dire emergency when there was little or no time for the normal protocol and/or the other, when there was no subordinate nearby to carry out both duties. In the case of Smith being seen to operate the telegraph: I contend it was the latter.
I envisage the following:
Smith would be in the outer wheelhouse with Murdoch. Olliver would be either leaving the bridge or arriving on it. Otherwise he might have been standing by as the Captain's 'runner'.
Moody would still be at his post in the wheelhouse with Hitchens.

My best guess is that Smith would assess the situation, discuss it briefly with Murdoch. Then, since protocol was all in such a ship, Murdoch would assume his previous roll. Boxhall was on his way below decks.
By prior agreement, Murdoch would sing-out hard-a-starboard when the engine order was executed on the telegraph by Smith. This would let Smith know where the wheel was. Both Hichens then Moody would acknowledge that the order was in fact carried out.
This had to be the case since otherwise, Olliver would be at his station behind Hitchens and would not have seen Smith operating the telegraph.

In fact, in Anchor Line passenger ships, this might just be the scene on the bridge approaching or leaving the the pilot station in a narrow water way when engine movements might be required.

As for the timing expression of 'half-a-minute'. I would caution you not to take that expression too literally. In the UK, there are several expressions used to describe a very brief period of time. 'Half-a-minute', 'wait-a-minute',
'wait-a-mo' are but a few. In Scotland they have the ultimate 'wait-a-wee-minute'. that is most definitely less than 60 seconds! In the States you have a New York version if I remember correctly!

I'm sure you'll agree the best 'guess' we can get on timing lies in the evidence supplied by the two Quarter Masters Hitchens and Olliver and the turning time tests made on Olympic. From these we have about 55 minutes between bells and impact - Ship's steering compass showed an alteration of about 2 points (22.5 degrees) during an approximate time of 55 seconds and 37 seconds to change a sister ship's head by 2 points at a known speed.
None of these three sources give exact values for Titanic. It follows that it would be incorrect to attribute such values to a second by second timing sequence.
The reason we have to accept Hitchens's 2 point to port evidence is simply because that apart from what he heard, that was the only visual contribution to evidence he could give. In fact his first utterance on the subject was volunteered by him during his description of the event. Then he said 'about two points'.
The only other treatment we can make about this is also based on approximate reckonings about time. We have to start somewhere. Your works suggests different scenarios which places is in the grey area as regards what really did happened

The only way Beesley could know the ship was actually moving ahead was by observing relative motion - i.e. by ripples from the ship's side (which he would not be able to see) or by a trail left by an overboard discharge. If by the latter, I'm not the least surprised! A ship does not come to a complete standstill unless forward and backward momentum is in equilibrium. A ship tied to a dock in still water will move!
Smith would have had the boats prepared as part of a pre-determined procedure. He would not have moved the ship after he knew the full extent of the damage and that boat launching had become a reality.
In any case any corrective course order had to come before Smith received his first evidence of serious damage.

As for the Zig-zag turn. To be effective, this has to be a seamless operation. On a fast ship it cannot be an afterthought.
You will note that in both cases, Boxhall has Murdoch telling Smith he was 'GOING' / 'INTENDED' to port/to hard-a-port round the ice. 'The world is full of good intentions'.
According to Rowe, when the berg passed him at the aft bridge it was not in contact with the stern - close to it, less than 5-10 feet in fact.
The ship was already slowing down at that time and probably loosing steerage-way due to propeller turbulence. It would be quite a few minutes and a kick ahead on the engines before the rudder would be effective again.
have you factored-in the turbulence effect on rudder efficiency during the time the shafts stopped turning until they came to a complete standstill. We know that the minute the engines started going astern, the rudder would need to be put mid-ship to avoid any unwanted change in the ship's heading.

What I do know about the effect of a strong push on or near the point of lateral displacement is that the vessel will most definitely be moved to the opposite side of the applied force. How far, depends on the force. I also know that such force applied to a moving ship will cause an un-looked for reactions in the way the ship swings. In certain cases it has the effect of making the ship slalom. i.e. briefly cant her head toward the applied force. I don't think this happened then.

The main thrust of my argument lies in the facts that the ship was slowing down the minute she swerved left and the engines stopped turning. Her steering efficiency fell off rapidly at the same time. A Zig-zag, to be effectively would need to have taken place seamlessly with the first helm order and with the engines still running. I am quite sure that Murdoch knew all of this. As you pointed out, he had previous experience and was a quick thinker.
I also do not think Titanic had enough momentum or rudder efficiency left after impact to get to a point 4000 feet NW of the berg. However I am willing to be convinced otherwise.

Regards,

Jim.