| Author |
Message |
    
tom bates
Member
Username: system
Post Number: 32
Registered: 8-2002
| | Posted on Tuesday, September 10, 2002 - 11:53 pm: | 
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I heard there was some secret adjustments made to the engines on the Mauretania is this ture and what was here top speed.The uss nimitz top speed is 60 knots i think. |
Michael H. Standart
Moderator
Username: mstandart
Post Number: 4447
Registered: 12-2000
| | Posted on Wednesday, September 11, 2002 - 7:32 am: |
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I don't know about any secret adjustments, though my understanding is that the top speed of the Maurataina was around 26-27 knots.
And the top speed of the Nimitz is not 60 knots. Not even close. She's in the 30+ knot range.
Conterary to some popular opinion, nuclear power does not give a ship some sort of magical capabilities. When you get right down to it, a nuclear powered vessel is a steamship plain and simple. The unique capability such a ship has is that she can sustain her top speed without having to worry about running out of fuel.
Cordially,
Michael H. Standart
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tom bates
Member
Username: system
Post Number: 33
Registered: 8-2002
| | Posted on Thursday, September 12, 2002 - 2:24 am: |
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The same person who told the story was in the navy said the Nimitz top speed is 60 knots Michael you said She's in the 30+ knot range but 60 is above 30 i rest my case. the story i herd about the secret adjustments made to the engines on the Mauretania is (cunard was aware of the germans' intentions to set a new speed record so in 1928 the Mauretania is takeing out of service for seven weeks in order for top? secret adjustments made to the engines and top secret pumps and condensers installed..and her top speed was 32 to 39 knots)thank you for you time and i am looking for a empress of ireland thank you
tom bates |
Dave Gittins
Member
Username: gittins
Post Number: 761
Registered: 4-2001
| | Posted on Thursday, September 12, 2002 - 4:01 am: |
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Who told you the story, Tom? Hans Anderson? |
tom bates
Member
Username: system
Post Number: 35
Registered: 8-2002
| | Posted on Thursday, September 12, 2002 - 4:57 am: |
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sorry i for got to put in shipbuilder in and i am looking for a empress of ireland shipbuilder thank you could you help me any info will be appreciated tank you |
Michael H. Standart
Moderator
Username: mstandart
Post Number: 4454
Registered: 12-2000
| | Posted on Thursday, September 12, 2002 - 7:56 am: |
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Tom, I'm sorry, but you have no case to rest. I was stationed on the USS Geroge Washington, which is a Nimitz class ship, I've been on the bridge, I've seen the brass plaque on the Engine Order Telegraph (Which give actual revolution and speed figures!) and I know what these ships are capable of. It's nowhere near 60 knots. Never has been, and never will be. Cut that by half and you'll be in the neighbourhood. I can't get more detailed then that.
Do the math yourself with these figures;
Length;1088ft Width;257ft Draft;37 feet and a mass of up to 102,000 tons at full load. The limiting factors are hull form and the actual horsepower available to push that mass through the water.
Propulsion is provided by two A4W reactors providing steam to geared turbines at 280,000 shaft horsepower which is close to identical for conventionally powered ships of the same type.
As to the story you "Heard about", beware of such. Mr. "I Heard" has a notoriously poor track record for accuracy.
Now if you have some documented sources for the claims regarding the RMS Mauritania, I'd be interested.
Cordially,
Michael H. Standart
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David G. Brown
Member
Username: brown
Post Number: 866
Registered: 12-2000
| | Posted on Thursday, September 12, 2002 - 1:53 pm: |
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There is a limit to everything.
The maximum speed of a displacement hull vessel (like a big ship) is a function of its waterline length. The formula is 1.34 x SQ RT Waterline. A ship with a 1,000 ft waterline reaches this so-called "hull speed" at a bit over 42 knots.
Once a displacement hull vessel reaches its hull speed, applying more power simply "digs a hole" for the stern and results in little additional (if any) speed. Designers have found some ways to "cheat" on hull speed.
The U.S. Navy's famous 4-piper destroyers of the 1920s were extremely narrow and "nuttin' but engines" below decks. They could exceed their theoretical hull speed but only at an enormous expense in fuel. And, when they did, their fantails were reportedly in a self-dug hole more than 20 feet deep. Can't vouch for the size of the hole, but photos of them "at speed" show an alarming wall of water on either side of the stern.
Extremely narrow beam like those destroyers was tried on passenger vessels, but with limited success. Passenger ships require high superstructures, so quickly became too narrow for good stability. Also, the energy needed in terms of tons of coal for a 4-piper to exceed hull speed was far beyond anything a commercial ship could afford.
Other methods of "cheating" hull speed have been found. Most often, they involve finding a way to increase the effective waterline length without increasing draft or the friction of the "wetted surface" of the hull. Another trick is to change the shape of the bow wave with "bulbs" and other odd shapes on the stem. Some designers have claimed they could get speeds of 1.4 or 1.45 times the SQ RT of the "at rest" waterline length.
Skin friction is a major problem in large, high-speed displacement vessels. One way to have increased Titanic's speed (and the other riveted construction ships of the era) would have been to reverse the directly of the overlap on the vertical butts between plates. Titanic's were lapped so the "step" of the overlap faced aft. This seems the logical way. However, the aft-facing step causes a burble in the flow of water, which creates drag. Facing the step forward causes water to "pile up" in the butt, which forms a smooth wedge to improve the flow of moving water along the hull. The gain is slight, but measurable.
The speed of naval ships is always considered as "secret" despite the fact that accurate numbers are available. And, navies often issue "disinformtion." I recall during the Gulf War that a U.S. Navy aircraft carrier departed the East Coast with fanfare. Seemingly hours later it was reported in action. Dividing the distance by the time required the ship to have made in excess of 55 knots. The rumor mill was full of stories that the carrier actually made speeds illegal on some freeways.
What the military did not say, however, is that the ship was "in action" only because its aircraft could fly exponentially faster and farther.
My river ferry is designed to "push" against the pier while boarding passengers. We don't tie up, just keep the engine in forward tt slow speed. Special pusher "knees" hold the vessel at 90 degrees to the pier. We have found a specific RPM at which this pushing works best. Logically, Mr. Spock, this has been dubbed "wharf speed."
--David G. Brown |
Michael H. Standart
Moderator
Username: mstandart
Post Number: 4455
Registered: 12-2000
| | Posted on Thursday, September 12, 2002 - 5:44 pm: |
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<groan> Wharf Speed.
David, that was bad! 
Cordially,
Michael H. Standart
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tom bates
Member
Username: system
Post Number: 36
Registered: 8-2002
| | Posted on Thursday, September 12, 2002 - 7:18 pm: |
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What do you mean by this Michael (Now if you have some documented sources for the claims regarding the RMS Mauritania) I'd be interested.
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Shelley Dziedzic
Moderator
Username: shelley
Post Number: 984
Registered: 4-2001
| | Posted on Thursday, September 12, 2002 - 10:13 pm: |
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Dave- you may be just the man to exlain the Yourkevitch bulbous bow thing to me- how does that help stability and speed? Was this experimental on Normandie? |
Yuri Singleton
Member
Username: yuris
Post Number: 303
Registered: 5-2001
| | Posted on Friday, September 13, 2002 - 2:28 am: |
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Ok, I worked with a former US Navy ordanence, person. He was on a nuke carrier called the George Washington I believe, back during the Vietnam War. (Could be wrong on the name.)
Anyway, he told me about a time that his ship was docked in Virginia back in the late 60's, and that evening there came word that all crews' leave was cancelled and all hands had to report to their stations immediately. So within about 3 hours, the ship left port just as the sun was going down. He said that he had never heard the engines running as loudly as they had that night, and that the ship was vibrating tremendously all night as well.
So the next morning he wakes up for his shift on the flight deck and discovers that the carrier is now cruising slowly near the coast of an island. Turns out, its the coast of Cuba. He showed me his own calculations of time, distance and speed. And the result was that the ship must have been traveling at over 60 MPH, (yes MPH, he did the numbers in MPH instead of Knots.).
Now, he told me that was the fastest he had ever known the ship to travel. That, or any ship. The only other time he witnessed a large ship travel so fast was when he was on another carrier off the coast of Vietnam and had to respond to a distress call in the Gulf of Tonkin or something. That ship was traveling at over 40 MPH that time.
Truth, or tall tale? I personally believed the guy's story because he seemed genuinly sincere about it. He wasn't the story telling type. But of course I have no way to know for certain.
Yuri |
David G. Brown
Member
Username: brown
Post Number: 867
Registered: 12-2000
| | Posted on Friday, September 13, 2002 - 2:50 am: |
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Shelley -- I'm not a naval architect, so I can't give a definitive answer on how a bulbous bow works. I understand it changes the bow wave and the flow of water, but beyond that...I will defer to my betters.
A bulbous bow is not for stability. It is to increase speed and/or fuel economy on a large displacement hull.
Stability control is a different animal. Adjustable fin stabalizers are the the way it is done now. Titanic had bilge keels which helped to dampen roll.
Modern fin stabilizers are like stubby wings that extend at 90 degrees to the hull. A gyro sensing unit causes the fins to work opposite to the natural roll of the vessel. If the ship is rolling naturally to port, the fins try to counter by rolling the ship to starboard. The fins work much like ailerons on an airplane, although they look more like small rudders sticking out of the hull.
A little bit of stabilizing is a good thing, but too much can produce an uncomfortable, jerky ride. As I recall, too much control can also cause physical stress on the framework of the ship. Perhaps one of our big ship (large vessel, not captain) drivers can add more to this. Today's systems are pretty complex with computers to control both the angles of the fins and the speed of their response.
On some vessels the fins stick out beyond the side of the ship. This is most often the case on older yachts. Woe betide the captain who docks without retracting the fins on one of those boats. I know at least one stabilizer manufacturer that equips its units with sensors to detect boat speed. If the speed drops below a pre-set amount, the fins retract automatically.
Some inventors have tried to come up with ballast shifting systems in which water is moved to the high side to counteract rolling. In theory, this should work, but it's hard to get the water moving properly. I also recall that on the Eastland (the ship that rolled over in the Chicago River) they would roll barrels full of water from side to side to counteract listing caused by movement of the passengers.
--David G. Brown |
Dave Gittins
Member
Username: gittins
Post Number: 766
Registered: 4-2001
| | Posted on Friday, September 13, 2002 - 5:59 am: |
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"Sailors will say anything when they are ashore."
Captain Stanley Lord. |
Michael H. Standart
Moderator
Username: mstandart
Post Number: 4459
Registered: 12-2000
| | Posted on Friday, September 13, 2002 - 6:38 am: |
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Tom, when I refer to documented sources, I'm talking about technical papers, data, journals, in short anything actually in writing from a credible source. Newspapers don't count BTW.
Yuri, I suspect your friend may have been pulling your leg a bit. I spent 20 years listening to Golly-Gee-Whiz-Whillikers-Wow stories like that from 'tween the decks, but the problem with the lot is that they can't get past the laws of hydrodynamics. With any given hull form, you can only get so much speed out for the power available. After that, you could double the horsepower and at best, get only one or two knots extra, and at that, at a horrible expence in fuel.
A lot of these stories come from people who have little knowladge or understanding of how and why ships work as they do. You would be absolutely stunned at how many Navy people don't know an awful lot about the subject outside of what is covered by their own ratings...which isn't as much as you might think.
And whatever ship this was, she couldn't possibly have been the George Washington. At that time, the name was carried by a ballistic missile submarine which remained in service until 1985. The current George Washington (CVN-73) was commissioned in 1992. For the Naval Vessels Register listing, go to http://www.nvr.navy.mil/nvrships/details/CVN73.htm
For the submarine which carried the name, go to http://www.subnet.com/fleet/ssbn598.htm
The only nuclear powered carrier in service at the time you mentioned is the USS Enterprise (CVN-65) You can see a little bit about her at http://www.nvr.navy.mil/nvrships/details/CVN65.htm
Cordially,
Michael H. Standart
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Tracy Smith
Member
Username: tracy
Post Number: 1126
Registered: 12-2000
| | Posted on Friday, September 13, 2002 - 11:07 am: |
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And Scotty was NOT the Chief Engineer of this particular Enterprise, either......  |
Dave Gittins
Member
Username: gittins
Post Number: 767
Registered: 4-2001
| | Posted on Friday, September 13, 2002 - 11:28 am: |
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I have a paper by a naval architect on the Nimitz class carriers. (I must admit I don't 100% understand it). Based on publicly available material, he puts their top speed at about 33 knots. Perhaps they can squeeze out one or two more knots if the fate of the USA is at stake, but there's not a lot of point in that, when planes and missiles are much faster. And remember, a carrier is useless without her escorts. She's really part of a big team, so the team must keep up, with a bit in reserve.
Mauretania's original top speed was about 26 knots. She was overhauled on several occasions, notably in 1921/22, when she was converted to oil firing. That gave her a bit more speed and she regularly made 26 knot crossings in service conditions. In 1929, she lost the Blue Ribband to Bremen, which crossed west-east at 27.8 knots. Soon after (I've not got the exact time) Captain Rostron had a final fling with Mauretania. She was pretty clean after another refit and Rostron thrashed her east-west at more than 27 knots. (Figures for the exact speed seem to vary). Bearing in mind that Rostron got some help from the Gulf Stream, it's safe to say that Mauretania could manage 27 knots in her final form. |
Shelley Dziedzic
Moderator
Username: shelley
Post Number: 985
Registered: 4-2001
| | Posted on Friday, September 13, 2002 - 2:56 pm: |
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Was the top speed of the UNITED STATES 42 knots? Thanks for the explanation of stabilizers Dave- marvelously understandable! Was a scenario like that of the Posideon Adventure -fictional though it was- in reality possible? |
David G. Brown
Member
Username: brown
Post Number: 868
Registered: 12-2000
| | Posted on Friday, September 13, 2002 - 3:47 pm: |
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Shelley-- Any vessel can, in theory, be capsized. In my latest book, "White Hurricane," there are two 500-footers documented to have been seen belly-up after the storm. One, the Charles S. Price, floated for several days in that condition.
Great Lakes ships like the ones in "White Hurricane" are much shallower draft than ocean-going cargo vessels of the same size. This means they have less stability for a variety of mumbo-jumbo naval architect reasons. If a passenger liner were improperly ballasted, it could become "tender" (roll easily) and, therefore, more likely to capsize--like the Great Lakes freighters.
You need some outside force to roll the ship over on its top, however. A passenger liner could roll on its side, but that would extend the center of buoyancy outward toward the roll. (Ooops, didn't mean to get too technical.) The ship would sink, but on its side. To capsize it belly-up, you would need some outside event like the fiction writer's favorite "rogue wave."
During the "White Hurricane" ($$$ 3X) the waves were 35 feet or better. And, they were plunging breakers, not smooth waves. Couple this with no sea room--that is the ships simply ran out of lake and had to turn around or be pounded to pieces on shore. During those turns, each vessel found itself in the trough of the waves. More than likely that induced fatal rolling sending the ship over on its side. The force of the wave finished the job. Of course, this is speculation because nobody survived any of the capsizes to describe what happened.
One curiosity of shipwrecks is how depth determines the attitude of the wreckage on the bottom. Given enough depth, a foundered vessel will regain its stability after it sinks and return upright. Note that the forward portion of Titanic is bolt upright on the bottom. The capsized ships on the Great Lakes from the 1913 storm are upside down. They sank in water only a few hundred feet deep, so did not have time to regain stability and become upright again.
There is one exception to that rule with regard to the ships sunk on the lakes in 1913. That is the wreck of the Wexford, which was built for salt water service. It is upright, indicating that it did not capsize like those ships designed and built for Great Lakes service. This seems to indicate that its deeper center of gravity (oops, technical jargon again) kept it upright in the storm. In Wexford's case, it appears the waves simply batter the ship into submission.
So, could the Posideon Adventure happen? Sure. Could you win the Lottery for the third time? Sure. However, neither occurrence is likely in the real world. But in fiction...where is that rogue wave I left on the desk yesterday morning?
-- David G. Brown |
tom bates
Member
Username: system
Post Number: 38
Registered: 8-2002
| | Posted on Friday, September 13, 2002 - 10:07 pm: |
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Where am i soposto get that stuff Michael Do you have the book The cunard turbine-driven quadruple-screw atlantic liner Mauretania page v or 5 And do you know whare i can get a aquitania shipbuilder do'nt tell me to go to the libray they dont have it |
Michael H. Standart
Moderator
Username: mstandart
Post Number: 4462
Registered: 12-2000
| | Posted on Saturday, September 14, 2002 - 1:30 am: |
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Actually, I will suggest you go to the library. Some of thevery best researchers start right there. Ever hear of interlibrary loan? Even if your local library doesn't have a particular book, if it exists in general circulation, they can get it. Also, how about contacting Cunard? Their website is at http://www.cunard.co.uk/
You could also do an internet search, or you could go looking for books on the subject by way of the internet.
And you might want to consider discussing the source for your information about the secret modifications you're talking about. You didn't just get it out of nowhere did you?
And we have some subject experts who post right here on ET who could help you out. The Sauder brothers for example.
Lot's of possibilities out there if you're really interested, but you have to take the initiative on this.
Cordially,
Michael H. Standart
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Yuri Singleton
Member
Username: yuris
Post Number: 304
Registered: 5-2001
| | Posted on Saturday, September 14, 2002 - 2:03 am: |
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I can't believe he was pulling my leg. He was too sincere. But he may likely have been wrong and thought he was correct.
In any case it astounded me at the time that a vessel as large as an aircraft carrier could actually move through water at that kind of speed. If it isn't possible then I guess you can't argue with physics. Oh well.
You know, I've always wondered why Titanic had those fins of metal that stuck out from her hull near the bilge on either side. Anyone care to explain those fins?
Thanks,
Yuri |
Adam Leet
Member
Username: leet
Post Number: 283
Registered: 5-2001
| | Posted on Saturday, September 14, 2002 - 2:11 am: |
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This reminds me, according to Tom Clancy's "Carrier", there were rumors that the Enterprise was able to achieve close to 40 knots during a speed trial off the Virginia capes. I didn't know if it had any truth, but the ship *did* have eight PWRs for power plant.
Adam |
Michael H. Standart
Moderator
Username: mstandart
Post Number: 4463
Registered: 12-2000
| | Posted on Saturday, September 14, 2002 - 3:06 am: |
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Yuri, what you're talking about there are the bilge keels. What they do is to minimize the rolling of the ship.
Cordially,
Michael H. Standart
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Yuri Singleton
Member
Username: yuris
Post Number: 306
Registered: 5-2001
| | Posted on Saturday, September 14, 2002 - 2:14 pm: |
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From the pictures of the bilge keel, it doesn't look like it was big enough, compared to the rest of the ship, to have much of an effect. Was this feature considered normal to ships then? Or was it more of an experiment?
And considering its location on the hull, shouldn't it have been destroyed by the iceberg? (Assuming that the iceberg was still that close to Titanic as it passed amidships.)
I wonder if its presence on the wreck indicates that the ship had definetly cleared the iceberg by that point?
Yuri |
David G. Brown
Member
Username: brown
Post Number: 872
Registered: 12-2000
| | Posted on Saturday, September 14, 2002 - 6:28 pm: |
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Yuri -- the bilge keel works not only by its width, which is small, but also by its length. On Titanic, the bilge keels were equal in length to about half the ship's overall dimension. That's a lot of square feet of bilge keel to interact with the water. Also, water is much more dense than air. This means that smaller appendages will provide much larger results than on an aircraft.
Good thinking on the affect of ice on the bilge keel. It would certainly have been easily damaged compared to the rest of the ship if it came into contact with the berg. For that to have happened, however, the underwater shape of the iceberg would have had to remain pretty much the same after the accident as before. This is highly unlikely. And, I think that Titanic did a lot of damage to the ice as well. That may explain why direct ice damage stopped so abruptly.
There will be more to come on the damage to the iceberg...after Cap'n Erik's big gam in Topeka
-- David G. Brown
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Noel F.Jones
Member
Username: ver1tas
Post Number: 27
Registered: 7-2002
| | Posted on Saturday, September 14, 2002 - 7:02 pm: |
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BULBOUS BOWS:
Shelley: I am not aware that Vladimir Yourkevitch had a bow configuration named after him. In "Normandie" he seemed to be following German practice in "Bremen/Europa" in that specific, although his overall hull design did have innovations.
The following does not purport to be a complete or definitive exposition of the concept:
Projections forward of the forefoot in the form of ram bows for combat purposes have been around since ancient time. As to whether the likes of Marcus Agrippa discerned any propulsive advantage accruing from the ram bows of their ships is a matter for further research. (Octavian's naval forces commanded by Agrippa defeated those of Marcus Antonius and Cleopatra at Actium September 02, 31 BC).
'Ocean greyhounds' notwithstanding, it was the Japanese naval architect Innui who first applied the concept of bulbous bows to deep-drafted full-bodied vessels such as bulk carriers and tankships in the 1950s.
Aircraft, and submarines when in the fully submerged condition, are totally immersed in their sustaining fluids. Surface ships on the other hand operate at the air-water interface which poses a problem in that the underwater pressure field generated by the ship's forward motion can be relieved by a dynamic elevation of the surface in the form of what are known as 'gravity waves'. So called because the water is literally being dynamically elevated above still water level. At a tonne per cubic metre, in a ship-generated wave system the amount of energy this consumes at anything above 'dead slow ahead' can be considerable.
It was the Thames shipbuilder John Scott Russell who c.1841 first propounded a 'wave-line' system for abating this energy loss. It was Scott Russell and William Froude MA, 1810-1879 who largely transformed ship design from an empirical craft to a modern science. Froude determined that ship resistance has two main components, frictional resistance and wave making resistance (also known as 'residuary' resistance). Other physicists contributed academically but it was these two who really sold fluid dynamics to ship operators.
To digress awhile ....
If you're ever in Torquay, Devon, UK, take time to visit the Manor House Hotel which Froude originally had built for his home in 1867. There is a comemorative plaque to him alongside the reception desk. Froude was a close friend of Isambard Kingdom Brunel, designer of the "Great Eastern" and commissioned the latter's brother Henry to build a unique and spectacular flying staircase which spans the lobby. You can also see the tank in which Froude conducted his experiments on the rolling of ships and which now serves as the hotel swimming pool.
Nearby in Seaway Lane is a comemorative tablet placed there at the behest of international naval architects to mark the site of the world's first towing tank (the Admiralty Experimental Works 1872-86). It was here that Froude arrived at his enduring Law of Comparison and the Froude Number, the inverse of the Reynolds Number much referenced by fluid dynamists. After Froude's death his work was carried on by his son R.E.Froude and in 1886 the operation was moved to Haslar near Portsmouth.
And if you're ever in Dumbarton on the Clyde, there is a masonry bust and dedication to Froude on the gable end of the old Denny shipyard towing tank in the Glasgow Road, placed there at the behest of Peter Denny the shipbuilder. The Denny towing tank is now preserved as a heritage site.
To revert ....
The Victorian steam navy was equipped with ram bows and I wouldn't be surprised if someone in the service had noticed that there was some discernible gain in speed or fuel consumption to be got from these protuberances. More research might elicit something.
At a ship's designed service speed the bulbous bow generates a wave ahead of that of the main ship body, the trough of the former coinciding with the crest of the latter — in other words they cancel each other out. The effect of this is to suppress the formation of such 'gravity waves' and thereby lessen the propulsive energy demand so as to save on fuel or augment speed.
Another benefit of the bulbous bow is to lengthen the effective buoyant mass of the vessel and this tends to suppress the tendency to pitch and slam in heavy weather. The bulb can also detract from the spectacular "bone in the teeth" (actually a 'wave of translation') that springs from the cutwater of 'ocean greyhounds' at speed and which amounts to a further dissipation of energy. There is also some evidence that the bulbous bow reduces apparent frictional resistance, probably by replacing it with less-taxing eddy-making resistance.
There is an unresolved anomaly in the wave-profile damping effect of the bulbous bow ....
A ship under way generates three wave systems: 'bow-divergent', 'stern-divergent' and 'transverse'. The transverse system is mostly evidenced by the undulating profile along the run of the hull. The fully developed transverse system has an effect on design towards the stern in that the designer has to aim (by means of tank testing etc.) to achieve a crest in way of the screw propeller(s). According to trochoidal wave theory, the orbiting particles in the cresting wave will then be moving in the same direction as the ship and therefore the ship stands to gain an augment of speed (the diminution gradient of interpolated sub-trochoids is asymptotic and therefore infinite but particle orbiting ceases for all practical purposes at a depth about one half wavelength).
The aforementioned anomaly is that the effect of the bulbous bow lessens any benefit deriving from an optimised transverse wave profile.
Since the wave profile optimisation only occurs at her designed service speed and in deep water, whenever the vessel moves away from her service speed or enters shallow water the optimum wave profile decays and the augment of speed must fall away. Furthermore, wave profile optimisation becomes complex in triple or quadruple screw vessels where the outboard screws are necessarily positioned some considerable way forward of the inboard screw(s).
In view of all that it could well be that the greater benefit accrues from the reduction in wave making resistance of the bulb rather than wave profile optimisation.
The above does not purport to be a complete or definitive exposition of the concept.
BILGE KEELS
I notice something something going on in this thread about bilge keels.
Bilge keels extend to about 30 to 40% of a vessel's length and obviously offer a static resistence to rolling. Their disadvantage is that if the vessel is running out of trim or pitching they increase frontal area and exert a vertical component of resistence; in effect the vessel either tries to plane uphill against the gravity of her mass or downhill against her buoyancy.
Noel |
Shelley Dziedzic
Moderator
Username: shelley
Post Number: 986
Registered: 4-2001
| | Posted on Sunday, September 15, 2002 - 2:49 pm: |
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Thank you gentlemen- I am now enriched, informed and ready to dazzle the multitudes with my new-found knowledge. I am wondering if the bulbous bow configuration is standard on passenger and warships now? It has been awhile since I stood at the bottom of a drydock in Charlestown looking up at the hull of a 1040's Class Destroyer Escort. I hear they are Fast Frigates these days! Ah, Navy life- not a job- an adventure. |
tom bates
Member
Username: system
Post Number: 40
Registered: 8-2002
| | Posted on Monday, September 16, 2002 - 2:39 am: |
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I found pouf in the the book The cunard turbine-driven quadruple-screw atlantic liner Mauretania page 5 there is your pouf |
Michael H. Standart
Moderator
Username: mstandart
Post Number: 4468
Registered: 12-2000
| | Posted on Monday, September 16, 2002 - 3:09 am: |
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I'll be sure to check it out when I have the chance Tom. (That is, if you're referring to the Shipbuilder Specials. I have the reprints that were edited by Mark Warren)
Cordially,
Michael H. Standart
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tom bates
Member
Username: system
Post Number: 41
Registered: 8-2002
| | Posted on Monday, September 16, 2002 - 3:29 am: |
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Coud you tell me all the titles in the Shipbuilder reprint series Michael and im referring to the engineering reprint edited by Mark Warren thank you |
Michael H. Standart
Moderator
Username: mstandart
Post Number: 4470
Registered: 12-2000
| | Posted on Monday, September 16, 2002 - 3:46 am: |
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Tom, the Shipbuilder has been in business for well over a century and there is no way I could possibly give you every single title and special put out. The titles listed in the index of both volumns of Mark Warren's reprint alone are a formidable number and just cover the period of 1906-1914, and at that, only the liners. The publication is now known as Shipping World and Shipbuilder in it's current incarnation.
I have to wonder if even they could answer your question.
Cordially,
Michael H. Standart
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tom bates
Member
Username: system
Post Number: 42
Registered: 8-2002
| | Posted on Monday, September 16, 2002 - 3:55 am: |
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Michael i ment the 1970 Shipbuilder reprint series. And do you know if the shipbuilder is on microfilm? |
Michael H. Standart
Moderator
Username: mstandart
Post Number: 4476
Registered: 12-2000
| | Posted on Monday, September 16, 2002 - 5:48 pm: |
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Mmmmmm..if you're talking about the Great Liners of the Past series, I know of only one, and that the Maxtone-Graham reprint that I have. Unfortunately, it's no longer in print. As to whether the thing is on microfilm, I'd be surprised if it wasn't. Every once in awhile, somebody does a reprint project, and they have to get the material from somewhere.
Cordially,
Michael H. Standart
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tom bates
Member
Username: system
Post Number: 43
Registered: 8-2002
| | Posted on Tuesday, September 17, 2002 - 3:46 am: |
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How menny plans are in your Shipbuilder reprint books Michael and coud you post them thank you |
tom bates
Member
Username: system
Post Number: 44
Registered: 8-2002
| | Posted on Tuesday, September 17, 2002 - 3:58 am: |
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What are the names of the shipbuilder reprint books you have. The reprint books i have are The cunard turbine-driven quadruple-screw atlantic liner Mauretania and the ocean liners of the past queen mary |
Michael H. Standart
Moderator
Username: mstandart
Post Number: 4481
Registered: 12-2000
| | Posted on Tuesday, September 17, 2002 - 6:38 am: |
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The One's I have are of the Ocean Liners of the Past dealing with the Olympic and Titanic as well as the two volumn series edited by Mark Warren. I'm afraid that even if I had the means to scan and post the deckplans, (I don't) I still couldn't do it as all this material is copyright protected. I haven't counted how many deckplans I have by way of these books.
Cordially,
Michael H. Standart
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Brian Hawley
Member
Username: olympic400
Post Number: 88
Registered: 1-2002
| | Posted on Tuesday, September 17, 2002 - 7:21 pm: |
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Also around in addition to the ones Mike mentioned are Ocean Liners of the Past Aquitania, and Mauretania (1939), as well as Empress of Britain 1931. I am currently looking for these 3.
There might also be one for the Queen Elizabeth however I am not certain.
Brian
Check out my web page
http://www.bytenet.net/rmscaronia
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tom bates
Member
Username: system
Post Number: 45
Registered: 8-2002
| | Posted on Tuesday, September 17, 2002 - 9:07 pm: |
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yes ther is a Ocean Liners of the Past Queen Elizabeth brian |
Scott Reigel
Member
Username: scott_reigel
Post Number: 2
Registered: 7-2002
| | Posted on Wednesday, September 18, 2002 - 3:08 am: |
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Ocean Liners of the Past for Queen Elizabeth? Is this a reprint or an original issue? I'd love to see a copy.
Thought there were only 7 reprints from the Shipbuilder:
#1 Olympic/Titanic
#2 Lusitania/Mauretania
#3 Aquitania
#4 Empress of Britain
#5 Normandie
#6 Queen Mary
Unnumbered Canberra.
There are also the Engineering reprints by Mark Warren.
Lusitania
Mauretania
Aquitania
and various ships covered in Volumes 1 and 2
Have I missed any?
Not sure if Mauretania 2 might have been reprinted at some time as well.
--SDR
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Eric Sauder
Member
Username: eric
Post Number: 203
Registered: 1-2001
| | Posted on Wednesday, September 18, 2002 - 3:40 am: |
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Hi, Scott:
You're quite right. As far as I know, a Queen Elizabeth edition was never produced in the Ocean Liners of the Past series.
The Mauretania 2 edition of Engineering was reprinted as was that for Campania/Lucania.
Eric Sauder |
Scott Reigel
Member
Username: scott_reigel
Post Number: 3
Registered: 7-2002
| | Posted on Thursday, September 19, 2002 - 12:45 am: |
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Thanks Eric --
"The Queen Elizabeth: The World's Greatest Ship" by Winchseter Publications (c)1947 is probably about the closest thing ther is to a "Shipbuilder" on her. No plans, but you have to love the colorized photographs.
--SDR |
tom bates
Member
Username: system
Post Number: 46
Registered: 8-2002
| | Posted on Friday, September 20, 2002 - 1:49 am: |
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Michael did you check your book for the number of engine and dynamo room plans? and dose anny of your books cover the Empress of Ireland coud you answer thees qustins Ware was the dynamo room on the Empress of Ireland and how many
boilers,pumps and dynamos were there.Are there any plans of the engine,boiler and dynamo rooms?and did yo check out my clam on the Mauretania ?
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Michael H. Standart
Moderator
Username: mstandart
Post Number: 4499
Registered: 12-2000
| | Posted on Friday, September 20, 2002 - 5:35 am: |
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Tom, I've been so busy the past week that I haven't had time to check anything. I do remember the Empress Of Ireland and the deck plans are included.
I'll be out of town for four days to attend the Topeka Event that Erik Wood is hosting. I'll be taking my volumns with me so I'll have a look then.
Cordially,
Michael H. Standart
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tom bates
Member
Username: system
Post Number: 60
Registered: 8-2002
| | Posted on Friday, October 11, 2002 - 4:13 am: |
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Hears some thing you dident know the Mauretania went 29.7 knots from eddystone to cherbourg wich is a bout 106 miles in 1929 . |
Mark Chirnside
Member
Username: mark
Post Number: 1246
Registered: 1-2001
| | Posted on Saturday, November 9, 2002 - 11:49 am: |
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Trust me, some of us knew. 
If you ask me it's even more incredible that Mauretania briefly attained 32 knots for several hours in July 1933. For a 26-year-old ship designed to maintain 25 knots, isn't *that* something! I have nothing but admiration for her performance.
Best regards,
Mark.
Mark Chirnside, Warwickshire, England
http://www.hospitalshipbritannic.com/rms_britannic.htm
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Adam Leet
Member
Username: leet
Post Number: 305
Registered: 5-2001
| | Posted on Tuesday, January 14, 2003 - 4:05 pm: |
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I just remembered, I have a copy of Mark Warren's reprint of the Engineering publication on Mauretania. I also checked out page 5, as Tom suggested, but I didn't see anything suspicious there indicating incredible speed capabilities.
Anyone else have the publication?
Adam |
Mark Chirnside
Member
Username: mark
Post Number: 1332
Registered: 1-2001
| | Posted on Wednesday, January 15, 2003 - 8:19 am: |
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Yes. I'll check.
Mark Chirnside, Warwickshire, England
http://www.hospitalshipbritannic.com/rms_britannic.htm
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Mark Chirnside
Member
Username: mark
Post Number: 1334
Registered: 1-2001
| | Posted on Friday, January 17, 2003 - 6:22 pm: |
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I do have the publication. Whether I could find it or not was another matter. If you want any sources as regards some of the changes to Mauretania, I might be able to help as I've got some archival records on her from Cunard.
Best regards,
Mark.
Mark Chirnside, Warwickshire, England
http://www.hospitalshipbritannic.com/rms_britannic.htm
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Adam Leet
Member
Username: leet
Post Number: 307
Registered: 5-2001
| | Posted on Sunday, January 19, 2003 - 1:20 am: |
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There was a thread in the Lucy forum discussing the differences between the two. I just gave a brief summary of their external differences, but I'm sure you've got the best sources for mechanical differences.
Adam |
tom bates
Member
Username: system
Post Number: 126
Registered: 8-2002
| | Posted on Sunday, January 19, 2003 - 3:01 am: |
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It was betwen 1927 to 1928. I could not supply any more info that i did not post already. It was in the intro in the Mauretania Engineering reprint.
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