Rudder

Cal Haines

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Dec 2, 2000
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Hi Nigel,

Welcome aboard! No need to apologize, we're always happy to have another set of hands on the oars!

Have a look at the Reversing Engines discussion, further down in this section. You will find a lengthy discussion of the engine orders.

I'm curious about the Olympic trials that you mention. Could you provide some additional details?

Warm Regards,

Cal
 

Sam Brannigan

Member
Feb 24, 2007
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Hi all!

Just how powerful was the steering engine on the Olympic and Titanic. Is there any record of how it performed under emergency conditions during trials?

Sam
 
Jan 5, 2001
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Sam,

This may be of interest, but Britannic's steering gear failed after brief movement when the ship was listng by some twenty degrees. They used the propellers to turn her.
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Nigel,

Thanks for your post. I am also curious like Cal about the trials, could you tell us the source as well? Thanks.

Best regards,

Mark.
 

Senan Molony

Member
Jan 30, 2004
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As Parks said:
"So, was Titanic’s rudder big enough?"

I dunno, because I have techie-difficulties, but I did notice today a piece in the Waterford News of June 1912 saying that the Titanic's steering gear could have played a role in the disaster because "American marine engineers are nearly universally of the view that the Titanic's rudder was too small"...

This is surely the earliest ever airing of this familiar chestnut... wherever the truth might lie.

The Waterford News piece, which was only a few pars, then went on to report that British warships of the same tonnage as large passenger vessels routinely had rudders *twice* the size of their civilian counterparts.

The argument was that warships naturally needed greater manouevrability in a tight spot. The corollary, of course, is that passenger liners would be less manouevrable.

As I say, I have no idea whether rudder size played any significant role in the impact - obviously speed was the prime culprit - but it was very interesting to see the rudder question raised as early as June 1912.

I came across it when looking for something else, a little theory Hermann Soeldner and I are working on, but I can dig it out again and post it if it's of galvanising interest to anyone.
 
Mar 3, 1998
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Funny thing about subject matter experts, like those "American marine engineers"...where were they before the fact? It was accepted practice then, as it is today, that maneuverability is more crucial for warships than it is for merchants. Shipping line owners, and this would include the White Star Line, only pay for what they have to.

I'd wager that the crew of the U-103 had wished that Olympic's rudder could have been smaller still.

Parks
 
Jan 5, 2001
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Speaking of that, Lusitania and Mauretania had bigger rudders and more advanced hull forms, and they were built to Admiralty specifications.

However, I've read that their hulls had a hidden defect, costing Cunard thousands of pounds of extra fuel consumption over the years and robbing one knot off the ship's speed. It was in the article in 'The Great Ocean Liners.' Can anybody elaborate?

Best regards,

Mark.
 
Mar 3, 1998
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Mark,

I'm not aware that Lusitania's rudder was significantly larger than Olympic's, in surface area below the waterline. Olympic used an unbalanced design, while Lusitania used a semi-balanced rudder. That means that Olympic had more rudder up the stock, while Lusitania had more rudder before the stock. Just eyeballing the plans, it looks to me that Lusitania's rudder is slightly larger, but Olympic has the advantage of having a screw directly in front of her rudder. As Bill Sauder would explain, the Admiralty was concerned primarily with Lusitania having the entire rudder surface under the water, so that it would not be vulnerable to gunfire.

Eric Sauder explains in his book how the "deadwood" was cut away in Lusitania's keel to enhance her turning characteristics, but I haven't heard of any hidden defects. If there was a defect, it didn't keep Mauretania from surpassing 30 knots later in her life.

Parks
 
Jan 5, 2001
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Parks,

I was unclear before, I meant to indicate that her rudder was deeper and as all was below the waterline it seemed to me that it was larger. Then again, as you point out Olympic had a centre screw behind her rudder to help it.

I found it hard to believe the 'hidden defect' information in this article, as the Admiralty assisted with the hull, but then we know what rumours there are on popular historical subjects!

Best regards,

Mark.
 
Mar 18, 2008
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No. Quartermaster Hichens and Captain Smith stated how well the ships (Olympic & Titanic) react. If it was to small or slow to turn the ships would have not pass the sea trials and the test by the Board of Trade. Olympic's rudder remained the same during her career.
 

A. Gabriel

Member
Jun 13, 2018
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Philippines
Quoth the above post: "The total weight of the rudder is 101-1/4 tons, while its length over all is 78 feet eight inches and its width fifteen feet three inches. The diameter of the rudderstock is 23-1/2 feet.’

Unenlightened as I am, how can the rudderstock's diameter be larger than the rudder's width when the photos of the Olympic-class rudder show the hinged portion to be quite narrow in comparison to the blade? Is there something obvious which I am missing out on?
 

B-rad

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Jul 1, 2015
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The rudder stock is twenty-three and a half inches not twenty-three and a half feet, in diameter. So a half inch shy of two feet in diameter. Whooo, you got my brain going for a second. :eek:
 
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Mike Spooner

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Jan 31, 2018
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Interesting discussion between semi-balanced and unbalanced rudders. As I understand the Titanic rudder was rather out of date in designed. As the British Government gave Cunard a very low interested loan of over a period of twenty years to build the two ships. The Admiralty had a strong say in want type of rudder and base on a war ship were movability plays an important part giving a better chance dodging against shell fire in war years. I would of thought a rudder all underwater must be better than one party hanging out of water. As I see cruise ships to day are all under water. What type I don't know? I can see trying to keep the rudder in a straight line to prevent drag. However can see to assist a ship in a straight line by adjusting the propeller speed one turning fasting than the other one. If that is the case Lusitania and Mauritania have advantage's with four screws against three screws! As what type of power Lusitania and Mauritania used to move the rudder I don't know? As hydraulic power is used to day on large ships a considerably improvement over a gearbox and a steam engine. O though I thought what is used on the SS Shieldhall ship steam power rudder work very well, was far simpler than the cumbersome clumsy system as used on the Titanic. The Titanic rudder may of been the right size, but Olympic on her maiden crossing in New York had a difficult time in docking. Finger was pointing at the rudder not been big enough for docking purposes?
 

Kevin Tischer

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Dec 24, 2011
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I know they didn't have computers to help turn ships back then so how did the wheel turn the actual ship? I heard it was quite hard for the helmsman to turn the wheel hard over.
 
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Dec 2, 2000
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The helmsman wouldn't have done it directly. The wheel would have sent commands to the steering engine by way of the telemotor. Turning the wheel was hardly the problem. Getting the ship to respond to the commands sent to the rudder, that was the problem!
 

A. Gabriel

Member
Jun 13, 2018
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It gets worse, re modern cruise ships: some of them have no rudder entirely due to having azimuth thrusters. This was the planned design for Clive Palmer's Titanic II: the rudder would've been merely cosmetic due to the use of azimuth thrusters instead of the original propulsion mechanism.