Optimal speed to avoid collision

Arun Vajpey, even if the Titanic was going only 10 knots, and so covered the same distance in a longer time, the turning circle hasnt changed... it takes longer because the speed is slower... so even if the longer time means things happen in relation - faster, like the commands on the bridge and the action in the engine room and the rudder turning - the result doesnt change, it just takes longer.. because the distance from the berg to the titanic doesnt change, just the time to cover the distance... and if the distance isnt large enough and the turning circle is the same, it doesnt matter how fast you can make the rudder turn because even if your going slower... 500 yards want enough distance... ? the titanic needed 800 plus yards to turn sufficiently ( 2 degrees? ) ?
 
if the Titanic had been travelling at only 10 knots instead of 21.5 knots that she actually was, Murdoch's first helm order would have come when the ship's bow was 400 feet further away from the icerberg than it actually was that night.
Do you want to know what would have happened is the ship started her turn away from about 400 feet further back than what she actually did? She would not have contacted the berg in her bow. She would have, however, initially made contact with the iceberg in the vicinity opposite the fourth funnel, near the juncture between the reciprocating and turbine engine rooms, and contact would probably have extended further aft of that point to include the dynamo room. (see below.) The ship would have been lost if the damage to the hull caused flooding in those 3 compartments.
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The problem that most people have in conceptualizing the accident is that a ship turns like a motor car when going ahead. That is just not the way things are. It is more like motor car being run in reverse. Her stern swings out away from the direction of the turn. The danger zone is along the side of the vessel all away to the stern.
 
Just to add to the scenario above, where the turn starts about 400 feet further back from where it did. If it is realized early enough that the ship would strike the berg near her quarter if no further action taken, the OOW could order the helm shifted hard over to port in an effort to swing her stern away from striking. Timing is critical, but if pulled off successfully, the berg might have been sidestepped completely.

Lots of ifs.
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Just to add to the scenario above, where the turn starts about 400 feet further back from where it did. If it is realized early enough that the ship would strike the berg near her quarter if no further action taken, the OOW could order the helm shifted hard over to port in an effort to swing her stern away from striking. Timing is critical, but if pulled off successfully, the berg might have been sidestepped completely.

Lots of ifs.
Thanks for that Sam. I know that this is not an easy question to answer but given that Murdoch, probably the most competent officer on board was on the bridge, do you think that he could have timed the second helm (hard-a-port) order well enough that night to miss the berg going by your "if" scenario above at 10 knots?

I am thinking about your conjecture in another thread (to which I agree) that on the actual night, Murdoch quickly realized that an impact with the iceberg was inevitable and sought to minimize the damage. The one and only thing that I believe differently is that rather than assume that inevitability even before he gave the first hard-a-starboard order, I think that it was perhaps 6 or 7 seconds later when he realized that the berg was closing too fast and the ship was not turning enough.

Ironically, the reason I think that way is because my mind keeps going back to your serial diagrams in the article Encounter in the Night. Even if your thinking about distances have slightly changed since you published that article, I think the "blossom effect" of the closing icerberg is demonstrated extremely well. Adding my own medical knowledge to that, human depth perception is relatively mediocre and reduces at night. In other words and using arbitrary figures only, any man in Murdoh's position and with good vision might have not been able to make an accurate judgement of size-speed-distance when that berg at 1800 feet from the bow but be able to do so with a fair degree of accuracy at 1300 feet. (The distances mentioned are just examples to explain what I am saying).

Correct me if I am wrong but the way I read your earlier posts and opinons expressed elsewhere on this subject compared with the one above in this thread, Murdoch had no chance whatever of avoiding an impact with the iceberg that night with the Titanic going at 21.5 knots. But if the ship had been going at 10 knots instead, there was a chance of avoiding impact altogether provided Murdoch gave his helm orders at the right time, even allowing for a bit of luck to be involved.
 
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Just to add to the scenario above, where the turn starts about 400 feet further back from where it did. If it is realized early enough that the ship would strike the berg near her quarter if no further action taken, the OOW could order the helm shifted hard over to port in an effort to swing her stern away from striking. Timing is critical, but if pulled off successfully, the berg might have been sidestepped completely.

Lots of ifs.
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Only if the 2nd helm order is given immediately after the fist and the engines are left severely alone ;)
 
Slowing down in ice, fog, restricted seaways and weather is subjective, and not all ships are the same of course.
On a 21knot container ship we slowed down to around 15knots in ice at night and in fog, depending on the conditions and didn't maintain full speed. That's quite a reduction.
On the same run and conditions in a 12knot iron ore carrier, we slowed down to 8-10knots!
The container ship had an ice-strengthened bow so in clear ice conditions in daylight we just barrelled through it at 21knots. On the ore carrier we tried that at 12knots and put a hole in the bow from a bergy bit...
In other words it's not that simple, and often you don't know what's out there until you meet it.
 
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