Engines working in opposite directions

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Did Titanic have the ability to reverse one screw to the other.. As in on the Port Round could Murdoch have gone full ahead Starboard screw and full reverse Port?

- Hindsight is always 20-20
 
Jim Currie

Jim Currie

Senior Member
Did Titanic have the ability to reverse one screw to the other.. As in on the Port Round could Murdoch have gone full ahead Starboard screw and full reverse Port?

- Hindsight is always 20-20
Yes he did, every twin screw ship has that capability but it is not an emergency action. Such an action takes time and he did not have time to do that. Normally it is used as an assist to the rudder when turning in narrow, confined areas... not in open ocean.
Hope that helps.
 
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Thanks Jim, yes it helps, I guess it's not as simple a thing to set up as just popping the clutch and selecting reverse...
 
Stephen Carey

Stephen Carey

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Thanks Jim, yes it helps, I guess it's not as simple a thing to set up as just popping the clutch and selecting reverse...
Ha ha, no, not quite. I think I included a dit somewhere on this site copied from my Quora answers. It's quite a long job, then as now. Let me know if you want a copy.
 
Steven Christian

Steven Christian

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Maybe they didn't know how to double clutch...:rolleyes:
 
Mike Spooner

Mike Spooner

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I shall be sailing on the SS Shieldhall ship with triple expansions steam engines this coming week end from Southampton. I certainly be asking the questions on how to reversing the engines and time scale to so.
If any body else has a question to ask please let me know.
 
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Steven Christian

Steven Christian

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I shall be sailing on the SS Shieldhall ship with triple expansions steam engines this coming week end from Southampton. I certainly be asking the questions on how to reversing the engines and time scale to so.
If any body else has a question to ask please let me know.
Sounds like a cool trip. I'm envious. No questions offhand but a 30 sec video clip would be cool if they let you do it. Cheers.
 
Sec'

Sec'

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Running propellers in opposite directions to help swing the ship is only really effective while maneuvering with the ship barely moving, and takes a looong time. At full service speed the water would just stall/cavitate around he reversed prop.
The strain on the framing, blades, and shafting would make it very very risky.

I believe that they rang down 'Stop' prior to collision to avoid the fear utmost in their minds, having a turning prop striking the berg.
 
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Jim Currie

Jim Currie

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Running propellers in opposite directions to help swing the ship is only really effective while maneuvering with the ship barely moving, and takes a looong time. At full service speed the water would just stall/cavitate around he reversed prop.
The strain on the framing, blades, and shafting would make it very very risky.

I believe that they rang down 'Stop' prior to collision to avoid the fear utmost in their minds, having a turning prop striking the berg.
At last! A bit of common sense.

Your "belief" is spot on.
No experienced bridge officer would touch the engines if the intention was to steer the ship out of danger. However, the second the starboard bow hit any underwater obstruction - let alone ice - the first thought would be for the propellers.
During a hard LH turn, on a twin-screw ship, you would stop both props. Because if you simply stopped the starboard one, the thrust of the port one would negate any LH turning motion, and, as you say, the rudder would be useless due to turbulence and cavitation.
Unfortunately, when Murdoch stopped both props, the turbulence caused by them and the dragging center prop. would have rendered the rudder useless in a very short period of time.

By the way, having actually maneuvered ships driven by triple expansion engines, I can confirm that an emergency request for full astern was normally a two-part action-- STOP...then Full astern and always with a double ring. (telegraphs were chain-driven in the "olden days".;)
If I remember correctly, the reason for this was that four sets of rings in a noisy engine room would be heard as prolonged alarm-sounding bells which would be sure to be heard and immediately recognised as an emergency. Then, of course, there was also the changeover procedure from ahead to astern which took time and effort.
 
Tim Aldrich

Tim Aldrich

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No experienced bridge officer would touch the engines if the intention was to steer the ship out of danger. However, the second the starboard bow hit any underwater obstruction - let alone ice - the first thought would be for the propellers.
I agree with that statement Mr. Currie. I think any sane person, in charge of any sort of watercraft, even the jet ski squids, could agree that a loss of propulsion is, probably, the worst scenario outside of being afire.
 
Sec'

Sec'

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I agree with that statement Mr. Currie. I think any sane person, in charge of any sort of watercraft, even the jet ski squids, could agree that a loss of propulsion is, probably, the worst scenario outside of being afire.
And to add to that Olympic losing a blade on her maiden voyage would really make it fresh in their minds
 
Mike Spooner

Mike Spooner

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I was on the SS Sheildhall last Sunday down in the engine room and asked about the reversing. It takes about two second flat at 75rpm. OK the engines are considerably smaller than Titanic had. The steering gear as to Titanic design was quick to with two steam motors doing the work
I took a video of the working engines. The noise, heat with escaping steam in places was great stuff. But my video needs a bit of editing sort out before I show it.
 
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Jim Currie

Jim Currie

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I was on the SS Sheildhall last Sunday down in the engine room and asked about the reversing. It takes about two second flat at 75rpm. OK the engines are considerably smaller than Titanic had. The steering gear as to Titanic design was quick to with two steam motors doing the work
I took a video of the working engines. The noise, heat with escaping steam in places was great stuff. But my video needs a bit of editing sort out before I show it.
I presume you mean engaging the astern gear when you say "about 2 seconds, Mike? Ringing the telegraph takes about 2 seconds. ;)
 
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