Model Boat Mayhem
Mess Deck: General Section => Full Scale Ships => Topic started by: tony52 on September 22, 2010, 01:53:46 pm
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New evidence released today, or another twist to this one?
http://www.guardian.co.uk/world/2010/sep/22/titanic-secrets-criminal-decision-officers
Tony
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It's about time we had another story/rumour about the loss of Titanic, hasn't been one for a while. Last one I heard was that Elvis was at the helm...singing 'shaking all over'.
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Surely all this is going a bit far?
There's a perfectly simple reason why the wheel was turned the wrong way. Forget all the guff about different steering systems and all that. It was purely a fault in the films continuity.
As you will remember, only half the "model" Titanic was built. So when filming from/on the side that didn't exist the film was reversed. This meant that uniforms and all sorts of other things had to be reversed as well. But when the helmsman was told "hard a port" that's what he did. But he should have gone had a stbd, so when the film was reversed it would appear that he'd gone hard a port. Seemples. A film continuity error, pure and seemple. BY.
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Are you sure it wasn't because the propellors had been screwed on backwards Bryan? (and maybe the funnels installed back to front?) Withe theTitanic, anything is/was possible.
If Madame Patten has know this since the age of 10 then why has she only divulged it just as her novel is being published?
Colin
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Colin, do I understand that you don't agree with me? Think about it, watch the film again (at least that bit of it). Bryan.
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Bryan, I agree with you 100%. I was just being a bit sarcastic about the fact that this 'revelation' has coincided with the publication of Ms Patten's novel.
There is also a book on the market which suggests that it wasn't the Titanic that sunk but the Olympic and that the two ships swapped identities when Olympic was being repaired after the collision with HMS Hawke. The theory was that Olympic was structurally weakened by the impact and was sent to sea as the Titanic to find a suitable iceberg so that her owners couild cash in on the insurance. Of course the change was done in great secrecy.....
Colin
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I think Bryan is under the impression that the sinking of the Titanic only happened in a fictional film ok2
Anyway what is so special about a ship that didn't complete even one voyage and killed a lot of people in the process ?
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Bryan, I agree with you 100%. I was just being a bit sarcastic about the fact that this 'revelation' has coincided with the publication of Ms Patten's novel.
There is also a book on the market which suggests that it wasn't the Titanic that sunk but the Olympic and that the two ships swapped identities when Olympic was being repaired after the collision with HMS Hawke. The theory was that Olympic was structurally weakened by the impact and was sent to sea as the Titanic to find a suitable iceberg so that her owners couild cash in on the insurance. Of course the change was done in great secrecy.....
Colin
This is my favourite story. Even though it has been proven time and again that it isn't true, there are always a few people who don't like the facts getting in the way of a good story.. {-)
Jonny
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Anyway what is so special about a ship that didn't complete even one voyage and killed a lot of people in the process ?
I think that is what most people consider to be special about it!
Most ships complete many voyages and don't kill anyone - even the Isle of Wight Ferry.
Colin
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There have been a lot of people killed on a lot of ships Colin, while do we seem to celebrate this one.
If you lived down here you would be sick of hearing about it.
Even Malvina Dean the last survivor made a living giving talks on the sinking and she was only 2 months old at the time. She must have had some memory. {:-{
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There have been a lot of people killed on a lot of ships Colin, while do we seem to celebrate this one.
It caught the public imagination in a number of ways that's all. Height of the self confident Edwardian period, lots of posh passengers on board, maiden voyage, took quite a while to sink, possible rescue never materialised etc. etc. Ticked all the boxes really.
When the Empress of Ireland went down a couple of years later it made much less of an impact(!). No famous faces and overshadowed by the war.
In our local publioc library, over half the books on shipping are about the Titanic. I suspect it's the same all over the country. The legend feeds on itself. I've even got some books myself although they are of a technical nature.
Did enjoy the film though, especially when the ship broke in half.
Colin
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Will anyone be sailing on the cruise in 2012 which will follow the Titanic's itinerary? The cruise is on board the MV Balmoral.
http://www.titanicmemorialcruise.co.uk/?gclid=CPj91Ojvm6QCFUg-4wodzHEYDg
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That's Fred Olsen's cruise ship - not Waverley's companion!
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I thought the Waverley's companion was being brave, venturing across the pond. Thanks for the clarification Colin.
Tony
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{-) going to say- are they trying to replicate everything- even the MCA (DOT's replacement) ignoring it's regulations (not unlike the DOT in 1912)?!?!?
Glad I googled MS Balmoral and saw an ocean-going liner and not a small coastal vessel!!!!!
Greg
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Due to our location O0 O0 we in Oz see things in a different perspective O0 O0
Seems to make perfect sense, usual normal mistake didn't know his left foot, in this case his hand, from his Right %) %) %)
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Yea, seeing that article yesterday in the Telegraph made me laugh. {-)
Whatever became of the hustlers who tried to capitalize on the movie's popularity & wanted to build a replica of Titanic for modern day cruising? I remember looking over their website in '98 & thought it first had to be someone's attempt at satire but apparently it was legit until a few people regained their senses.
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There is a programme about Titanic on UK TV tomorrow Monday 26 Sept, Channel 4 at 9pm. The subject matter is the construction of the vessel from an enineering viewpoint. Apparently they have built a reproduction of part of the bow.
Probably worth a look.
Colin
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Looks very interesting from the trailer- including a rivetted full scale bow section/recreated engine room (large pumping station triple and boiler room methinks) as well as other things they have recreated.
Greg
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At about the time of the movie's release, a letter appeared in the Times recounting that in about 1932 an international convention was implimented changing the sense of the steering in all the world's ships to the modern intuitive method. The letter writer said that his father had been a sea captain and that, before the war, he had bought a car but had been unable to drive it because he could not master the steering! Does anyone know if there was such a convention? Googling for it doesn't produce much.
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Merchant Shipping (Safety And Load Line Conventions) Act 1932 (c.9)
FIRST SCHEDULE International Convention for the Safety of Life at Sea, 1929
Chapter V.-Safety of Navigation {no text}
Article 41
Helm Orders
The Contracting Governments agree that after midnight on the 30th June, 1931, helm or steering orders, i.e., orders to the steersman, shall on all their ships be given in the direct sense, e.g., when the ship is going ahead an order containing the word “starboard” or “right” or any equivalent of “starboard” or “right” shall only be used when it is intended, on ships as at present generally constructed and arranged, that the wheel, the rudder-blade and the head of the ship, shall all move to the right.
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Wow! Thanks for that speedy reply!
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Interesting that it took 19 years for the government to implement commen sense- anybody have any idea why it took so long after the the Titanic disaster?
Greg
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Interesting that it took 19 years for the government to implement commen sense- anybody have any idea why it took so long after the the Titanic disaster?
If it is shown that a bureaucracy is wrong there is a problem. Bureaucracies can't (or won't) punish themselves. Instead they will play a waiting game, putting off any allocation of blame. Eventually, all the staff associated with the old mistaken policy will have retired, died or moved on, and the new staff are free to change the policy with no loss of face or need to blame anyone. I suppose that takes about 20 years....
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I don't think the change was a direct consequence of the Titanic disaster but simply reflected the change from sail to steam - there were still a lot of sailing ships in service right up to the 1930s. It was also necessary to get International agreement and that would have taken a long, long time anyway.
Colin
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Apart what anything else that has been said, how on earth would Lightoller have any idea about whether the wheel was turned the wrong way or not? When the collision ocurred, he was off watch and fast asleep in his cabin! They would all have had far too much on their plate when they realised the ship was sinking than to start blaming someone for turning the wheel the wrong way after the deed had been done. It is generally accepted that if the ship had rammed the berg head on, it would have been very badly damaged, but also unlikely to have sunk. But I can't see anyone deliberately giving an order to hit it head on (human nauture) with only seconds to make the decision. More likely to try and avoid it and hope for the best. Even if it had been turned the wrong way, and someone did tell Lightoller, he would probably either have not have believed it, or if he did, would not have breathed a word to anyone, not even his wife!
I take it all with a pinch of salt as a ploy to publicise the book and would not set much store on an author who still thinks the TITANIC was a "boat!"
In any case, as soon as the officer of the watch ordered the wheel hard over, he would be watching the compass and ships head for signs of her answering, and any miistake would very quickly have been put right.
Bob
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Quite right Bob, the idea of the officers having a meeting in a cabin while the ships was sinking under them and passengers clamouring for places in the lifeboats is rather ridiculous. As you say, the OOW would have been watching for the ship's resposnse like a hawk and presumably it did have a rudder indicator on the bridge showing the actual helm position.
Colin
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The information in Wickipedia gives a short but quite comprehensive summary of the incident which is worth reading. especially subsection 7.2 :
http://en.wikipedia.org/wiki/RMS_Titanic
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Back in the days of the whipstaff, we never had these problems. Starboard was starboard! %%
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back in those days wasnt starboard steerboard ?
{-)
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we still have the same problem today..... say right - mean left, or say left and mean right........ just look in the house of commons!!!!
:embarrassed:
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A large model of the 'Titanic' photographed at Bury, North Manchester in 1998.
The builder had problems with this model, it ran into the bank on its maiden voyage. It was sold shortly afterwards.
(http://s3.postimage.org/f7HwA.jpg) (http://postimage.org/image/uperk7es/)
Tony.
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Titanic's Gloria Stuart (Old Rose) dies aged 100.
http://www.cinemablend.com/new/Titanic-s-Gloria-Stuart-Dies-At-Age-100-20841.html
RIP
Tony
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Hi Colin,
Just 2 things. 1, The rudder indicator would be mechanical and unlit in a unlit wheelhouse on a black night.
2, A vessel like the Titannic, when it starts to move at speed, I should think would take a long time to check it's turn then move back. After all she only had a single basic barn door rudder.
But at the end of the day it was a tragic accident with no reliable witnesses, with a huge loss of live. If the Master had survived under todays regs he would have probaly gone to prison and most certainly lost his ticket for recklessly hazarding his ship by not proceeding at a SAFE SPEED in Hazarded conditions.
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Good points there, I have seen a reference to the rudder indicator being electrical but that doesn't necessarily mean it would have been illuminated and they would have been concentrated on trying to see the iceberg clearly. As you say, it's really impossible to get to the entire truth after so much time has elapsed.
Straying slightly off the subject, there was also controversy concerning the Bismarck/Hood episode when Admiral Holland was accused of heading directly towards Bismarck for too long which meant that only his forward guns would bear. When the wreck of Hood was discovered the rudder was found to be turned to port showing that orders had actually been given for the ship to open her 'A Arcs' so as to bring her full broadside into action - unfortunately too late!
Colin
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A large model of the 'Titanic' photographed at Bury, North Manchester in 1998.
The builder had problems with this model, it ran into the bank on its maiden voyage. It was sold shortly afterwards.
(http://s3.postimage.org/f7HwA.jpg) (http://postimage.org/image/uperk7es/)
Tony.
Nice model. Makes a change from hearing about all the banks running into problems................
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Has anyone taking part in this so called "debate" thought about Captain Smith's Past? What types of ships did he "captain" etc?, Did he have a history of "Banging ships up?" So to speak?
I think you guys need to read a bit of history!
HIS "Captain Smith's" orders as being the master of the vessell, would have been the standing orders for any bridge OOW , therefore whould have been following his orders in any event, if the standing orders issued by the master where followed in this case, they would have done that "at the time" from the "masters" experience/ orders! I think you will find that Captain Smith, was about to retire and that this voyage of the Titianic, was his last "as we all know" claim to fame, infamy! What ever you want to call it, the guy was past his "sell by date" and things had moved on, do not forget, he was doing 21 kts in a 60000 ton plus ship, tripple screw, with only the third centre prop as a reversing engine/ manouvering engine.
I can run rings around you boys with this to be honest, but, sufficed to say, the bloody ship sank at the end of the day and alot of people died cos of it, OH! And by the way the Hood theorists have been proven wrong too!
It happened, we so called learned, get a life!
Paul...
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Seconded
Ned
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tripple screw, with only the third centre prop as a reversing engine/ manouvering engine.
I can run rings around you boys with this to be honest, but, sufficed to say, the bloody ship sank at the end of the day and alot of people died cos of it, OH! And by the way the Hood theorists have been proven wrong too!
It happened, we so called learned, get a life!
Paul...
Your 'rings' are a little wonky mate- the centre screw was a slow revving prop off the low pressure exhaust steam turbine- the two outer prop's were the reversing Triple expansion engine shafts.
Greg
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And Titanic's tonnage was 46,000 gross and 52,000 displacement!
Not sure what you mean by Hood theorists Paul, I was simply referring to the reports (and photos) from the expedition which discovered her wreck. I think the theories were all to do with what set off the explosion that actually sank her. I don't suppose that will ever be resolved.
Colin
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Your 'rings' are a little wonky mate- the centre screw was a slow revving prop off the low pressure exhaust steam turbine- the two outer prop's were the reversing Triple expansion engine shafts.
Greg
Not according to my drawings mate!
Paul...
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http://www.encyclopedia-titanica.org/titanic_prime_mover~chapter-0~part-3.html
According to the above the turbine was designed to cut in above 50rpm on the recips
The turbine was bypassed for manoeuvering and going astern
Ned
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I actually find this a very good read:
http://www.professionalmariner.com/ME2/dirmod.asp?sid=&nm=&type=Publishing&mod=Publications%3A%3AArticle&mid=8F3A7027421841978F18BE895F87F791&tier=4&id=076123ADBC76430FA727A38386136514
As with most Titanic related theories there is no definitive conclusion, which I think is why it is still debated to this day and why it continues to interest historians and mariners alike. I find it fascinating to try to understand the way in which a ships bridge operated in those days as opposed to how we operate a vessel today. Just reading that attachment above gives you a bit of an insight into the dysfunctional way in which the bridge team operated and how it would be extreemly difficult for any single member of the bridge team to know what was going on. It's also interesting to note that the compass was lit with an oil lamp!!
As for running rings around anyone, I'm not sure even the experts would be brave enough to say that because at the end of the day there are still many unknowns. As for captains reaching retirement I have seen first hand marine accidents involving captains both young and old and I firmly believe that we can train for the incident but we really don't know how we will respond until it happens. When it does is a young captain, alert and clued up on the latest practises but lacking in experience, any better than an old captain with a wealth of experience but not quite as up to date on the latest technologies?
We could debate that one forever and not reach a conclusion as well!!
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http://www.encyclopedia-titanica.org/titanic_prime_mover~chapter-0~part-3.html
After looking at the GA of this installation could anyone please answer the following question -
The centre shaft was driven by a Parsons (through flow) steam turbine. My understanding of steam turbines is that they should always use superheated steam to prevent the damage that would be caused to the blades by using saturated steam. In this set up the steam turbine uses exhaust steam from the after the LP recip. Would the steam be superheated after having been used in the HP, IP and LP recips thus removing the need for superheating or would the low pressure not cause damage to the turbine blades?
Thanks
Tony.
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The book I have got on the building of the Titanic and her sisters stresses that this was an early type of turbine and not very sophisticated. Presumably the design must have worked as Olympic had one and that ship had a long career.
Colin
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Saw a programme about the collision. Simulations seemed to prove that if the ship had turned to run headlong into the iceberg, although it would have caused major damage it would not have opened enough of the hull to sink her unlike the long gash that did.
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There is also a book on the market which suggests that it wasn't the Titanic that sunk but the Olympic and that the two ships swapped identities when Olympic was being repaired after the collision with HMS Hawke. The theory was that Olympic was structurally weakened by the impact and was sent to sea as the Titanic to find a suitable iceberg so that her owners couild cash in on the insurance. Of course the change was done in great secrecy.....
Is this the book you're thinking of? http://www.amazon.co.uk/Olympic-Titanic-Truth-Behind-Conspiracy/dp/0741419491 - this book actually debunks the Olympic/Titanic switch conspiracy, with detailed explanations of the many ways that the two ships differed from each other (the different promenade deck windows are just the start. I have this book in my own reference library, as it's the best (only?) reference source for converting a Titanic model to Olympic, and has a lot of interesting detail close-up photos of both ships.
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No it was Robin Gardiner's books:
http://www.amazon.co.uk/Riddle-Titanic-Robin-Gardiner/dp/0297815288/ref=pd_sim_b_2
and
http://www.amazon.co.uk/Titanic-Ship-That-Never-Sank/dp/0711034869/ref=pd_sim_b_1
Colin
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After looking at the GA of this installation could anyone please answer the following question -
The centre shaft was driven by a Parsons (through flow) steam turbine. My understanding of steam turbines is that they should always use superheated steam to prevent the damage that would be caused to the blades by using saturated steam. In this set up the steam turbine uses exhaust steam from the after the LP recip. Would the steam be superheated after having been used in the HP, IP and LP recips thus removing the need for superheating or would the low pressure not cause damage to the turbine blades?
Thanks
Tony.
Hi Tony,
A very good qeustion indeed.
The main reason would be the volume of steam at the low pressure exhaust from the recip's would be huge- to pass this through a superheater and makeit worthwhile the superheater would be massive, and so much condensate would be carried over it would be little more than a steam drier.
While today our understanding of superheated steam and it's properties is absolute so we can design turbines that are small in comparison to thier forebearers in relative comparison to the powewr they supply.
However don't go thinking that all high tech modern turbines are superheated and innefficient- the Oberon class subs using a nuclear reactor could not superheat of course, and using a 7 stage turbine they were very efficient, yet the last stage was almost water!
Greg
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I thought the Oberons had conventional power plants?????
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I thought the Oberons had conventional power plants?????
Oberon's were diesel/ electric subs definitely not nuclear
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Yes....& very quiet too.....one of our OZ Oberon Commanders got into a lot of trouble when one of his crew sold a photograph to a Perth newspaper of the USS Enterprise CV?? in the perescope cross hair viewer during a combined exercise north west of Exmouth in WA .....like :police: this cannot happen >>:-( >>:-( ...like this was not supposed to happen :kiss: :police: ....but it did!
The minister for Defence at the time was that {-) {-) Mr Beazley.........& instead of egg on his shirt [he was a very messy eater onboard HMA vessels] it was his face...... %) ....
I have tried to GOOGLE this story.....but as expected ....back then it was declared by our D of D as a hoax .........to save face for our US....friends........Derek
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Sorry...I know this is getting a little off track....but here is an extract from a much later incident....."New Depths in Australian - US Relations - the Collins Class Submarine"...where they acknowledge that a quiet sub can breach US defences ....Derek
"viii. American Recognition
Horden Wiltshire, former Commanding Officer of HMAS Sheean, has recorded of the
Collins submarines that the ‘media smoke screen has disguised the full potential of
the platform which, in an uncertain strategic environment, remains one of the most
versatile and potent in the Australian Defence Force’.110 The US too were soon to
discover just how potent. More positively for those associated with the Collins
project, such was the lauded but little reported, success of HMAS Waller at Nthe
RIMPAC 2000 naval exercises off Hawaii in May, that the US interest was
heightened. Despite being restricted by some aspects of its noise performance and
limitations in the combat system, Waller, in these structured events, pursued and
'sunk' a Los Angeles class nuclear submarine and in taking periscope photographs of
the aircraft carrier, Abraham Lincoln, demonstrated that it could enter into torpedo
range of the carrier denying detection.111 Just why there was such a dearth of
publicity surrounding Waller’s success may indicate further, the strength of the
interest in securing US involvement.
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On the subject of turbines and superheat, to the best of my layman's knowledge turbines generally require dry, though not necessarily superheated steam. The Isle of Man Steam Packet had been operating turbine vessels for close to fifty years before the first superheated boiler (Babcock & Wilcox sectional header type fitted to Manxman in 1955) was used.
I think (and I'm happy to be corrected in any of this) that it is the presence of condensate which leads to problems with out-of-balance forces and eventually blade erosion. How dry the exhaust from a reciprocating engine is I wouldn't know. I suspect that the overall design of the plant would a) design the main engines to leave the exhaust sufficiently dry b) construct the turbines with adequate strength to cope with the expected saturation level c) ensure sufficient vacuum at the condenser to minimise condensation within the engines. Certainly exhaust turbines were in use for a very long time, though I suspect that main turbine propulsion came first.
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I thought the Oberons had conventional power plants?????
You may be right Colin, one of the lads at work was project manager at Vickers on the first nuke subs there, I thought those were the O-boats, but I may be wrong.
Either way, the first nuke powered subs built there were turbines of course, and they had no superheaters and their turbine's worked with seven stages, the last being almost water; the real point of the post.
On the subject of turbines and superheat, to the best of my layman's knowledge turbines generally require dry, though not necessarily superheated steam. The Isle of Man Steam Packet had been operating turbine vessels for close to fifty years before the first superheated boiler (Babcock & Wilcox sectional header type fitted to Manxman in 1955) was used.
I think (and I'm happy to be corrected in any of this) that it is the presence of condensate which leads to problems with out-of-balance forces and eventually blade erosion. How dry the exhaust from a reciprocating engine is I wouldn't know. I suspect that the overall design of the plant would a) design the main engines to leave the exhaust sufficiently dry b) construct the turbines with adequate strength to cope with the expected saturation level c) ensure sufficient vacuum at the condenser to minimise condensation within the engines. Certainly exhaust turbines were in use for a very long time, though I suspect that main turbine propulsion came first.
You are correct in saying it is condensate which is the major unbalancing force in a turbine- rather like throwing ball bearings into a food blender. The turbines I mentioned in the early nuke subs at Barrow had specially designed blades on the last two stages to cope with the high saturation.
Recip's need dry steam in the cylinders, however the exaust in a condensing plant should be as wet and cool as possible- tjis means it's giving up as much energy as possible in working the engines, which as you also correctly say is reliant on having a large air pump to shift as much condensate as possible.
Turbines and exhaust turbines were actually developed along with each other as they were seperate technologies in themselves, yet lent themselves to being utilised in the same engineroom. Certainly in some o;ld steam manuals I have it mentions them both together around 1911 as bedfellows.
Greg
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Just out of interest, since yesterday's post I've been doing a bit of digging on the nature of steam. There seems to be a bit of a grey area in the definition of wet, saturated, dry and superheated steam.
From my experience of land-based steam usage (primarily for heating purposes) I have always used the term 'dry' quite loosely to describe steam which contains no obvious water droplets. In this instance it would be fair to say that the steam leaving the boiler was saturated, and indeed dry, but would become progressively wetter as it cooled on the way to its destination. Even with the best lagging in the world there must be some degree of condensate mist bound up in the flow by the time the steam comes to be used. The only way to avoid this situation is by superheating the saturated steam so that any cooling does not progress beyond the point at which condensation appears - i.e. the steam continues to behave as a gas until it begins to work expansively.
It appears that there are only really two important definitions here:
1. SATURATED STEAM - Steam at which the temperature of the steam corresponds to its boiling point at its current pressure.
2. SUPERHEATED STEAM - Steam which has been further heated until its temperature exceeds its boiling point at the current pressure.
From this it can be seen that any steam even fractionally cooler than Saturation Point will contain condensate and could be described as wet. Saturation therefore describes a boundary between wet and superheated steam. So DRY steam has to be either precisely on the boundary or it has to be superheated.
Thus much so-called dry steam is technically at least partly wet. In a theoretical sense there cannot be any absolutely dry steam in a non-superheated installation. In practice I think my definition of dry steam being that which contains no excessive presence of water droplets is probably the one which is generally recognised.
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Doesn't superheat depend on pressure as well as temp, Ie steam could still be considered superheated at 70 Deg C providing the absolute pressure was at -11 psi ( cheated a little here and looked it up) ;D
Most turbines use condensers after the final stage to ensure the maximum is extracted out of the steam, I know power stations utilise wast heat in between turbine stages as well to reheat the lower pressure steam.
Nick
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Like yourself nsa66 I have been further researching this subject and I hope you don't mind me adding the following to your research. Again like yourself my experience is of land based steam (mainly for heating purposes) and throughout the distribution network the steam mains would fall and be trapped at the lowest part, commonly known as a dirt leg, this would be to keep the saturated steam as dry as is practical. Steam mains were never designed with level pipe runs and branch 'take offs' were always on the top. Sometimes when a steam pressure reducing station was used a degree of superheat would occur over the reducing valve's seat.
Returning to the Titanic's power plant installation I came across this on tinternet. The article shows (in Part 3) that this type of installation, which uses a turbine to be driven from the exhaust steam from a recip plant was to save coal, rather than increase speed. The item's author is not 100% correct as the Titanic's tonnage is stated as 60,000 whereas Colin Bishop has already identified this to be incorrect.
http://www.history.rochester.edu/steam/parsons/part1.html
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Doesn't superheat depend on pressure as well as temp, Ie steam could still be considered superheated at 70 Deg C providing the absolute pressure was at -11 psi
Yes, that's right. The definition I have is that Superheated Steam has to have a temperature which is above its boiling point at its current pressure. So yes, if the BP of steam at -11psi was less than 70c then steam at 70c would be superheated.
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.. steam mains would fall and be trapped at the lowest part, commonly known as a dirt leg ...
Oh yes, and steam traps seemed to give trouble in inverse proportion to their size. The smaller the trap the bigger the pain in the @r5e!
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the bigger the pain in the @r5e!
Far worse were Spirax's modern replacement of the Ogden Pump. That was a pain in the ****
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Far worse were Spirax's modern replacement of the Ogden Pump. That was a pain in the ****
Oh yes I remember it well. Only ever saw the Spirax and it was not held in the highest regard by those familiar with the "Oggy". Why pump the condensate back to the boiler when you can leave it sitting in the pipework. Someone's bound to come and drain it off eventually.
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From my experience of land-based steam usage (primarily for heating purposes) I have always used the term 'dry' quite loosely to describe steam which contains no obvious water droplets. In this instance it would be fair to say that the steam leaving the boiler was saturated, and indeed dry, but would become progressively wetter as it cooled on the way to its destination. Even with the best lagging in the world there must be some degree of condensate mist bound up in the flow by the time the steam comes to be used. The only way to avoid this situation is by superheating the saturated steam so that any cooling does not progress beyond the point at which condensation appears - i.e. the steam continues to behave as a gas until it begins to work expansively.
It appears that there are only really two important definitions here:
1. SATURATED STEAM - Steam at which the temperature of the steam corresponds to its boiling point at its current pressure.
2. SUPERHEATED STEAM - Steam which has been further heated until its temperature exceeds its boiling point at the current pressure.
From this it can be seen that any steam even fractionally cooler than Saturation Point will contain condensate and could be described as wet. Saturation therefore describes a boundary between wet and superheated steam. So DRY steam has to be either precisely on the boundary or it has to be superheated.
Thus much so-called dry steam is technically at least partly wet. In a theoretical sense there cannot be any absolutely dry steam in a non-superheated installation. In practice I think my definition of dry steam being that which contains no excessive presence of water droplets is probably the one which is generally recognised.
You are correct on every count- permit me to clarify one point though- DRY STEAM is the boundary line between superheat and saturated- ANY steam taken from the boiler is going to be saturated, no matter what pressure it is at (though this doesn't really include flash steam for anyone that feels like being pedantic), however this can be overcome by the use of a STEAM DRYER, this usually looks very similar to a superheater but differs in detail- it has far less surface area and usually a single pass, allowing the steam to move at the same velocity as it would in the main steam pipe.
The purpose of this device is to keep the steam at the same temperature (within a few degrees) but drys it very well.
The reason for this device was that Recips with superheated steam needed constant maintainance- the high pressures and temperatures involved meant slide valves couldn't be used and had to have piston valves- which need a good oil film to work reliably- something that is hard at superheat temperatures.
Greg
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Thanks Gondolier, that tidies up the definitions nicely.
The description of the "steam dryer" is interesting. I'm not sure I've come across that before (or if I have, I may have confused it with a superheater). Would the dryer be incorporated into the boiler in the same way as a superheater? Whereabouts would this be fitted in, say, a scotch boiler?
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Hi nsa66,
In a Scotch it would normally be located in the dryback combustion chamber- if it was a wetback I imagine it would be in the flue smokebox, though I can't say I've seen any diagrams of them used in a wetback.
Greg
Ps- a quick search on Google books with 'steam dryer' brought up quite a few interesting publications with the definition and practical use of the 'steam dryer'.
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There is one book (actually two very large volumes) that actually contains facts in immense detail about these ships rather than endless speculation. It's called "Titanic": The Ship Magnificent and has a web site here (http://www.titanic-theshipmagnificent.com/). The content is of great interest to period ship modellers and explains the ship's fittings as well as the detailed construction of the hull and machinery. Copies are on Amazon at modest prices (Vol1 is most likely to be of interest to us) and as a bonus it doesn't contain a single sinking theory or survivor's recollection!
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... this doesn't really include flash steam for anyone that feels like being pedantic ...
Am I right in assuming that "flash steam" is essentially superheated steam in that (due to the nature of a flash boiler) it is further heated away from contact with the water - i.e. in effect the flash boiler acts as both steam generator and superheater in a single unit?
I have never come across flash steam except in magazine articles describing its use in very high speed steam-powered models. Has there been much use of flash steam (as opposed to conventionally generated superheated steam) in full size vessels? I suppose early attempts at high-speed running may have been candidates - light weight installation etc.
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Am I right in assuming that "flash steam" is essentially superheated steam in that (due to the nature of a flash boiler) it is further heated away from contact with the water - i.e. in effect the flash boiler acts as both steam generator and superheater in a single unit?
Yes, you assume correctly- the pressure vessel is kept at a very hot temperature- 'dull straw' if you were annealing steel to the same colour.
Some experiments (by White Steam Cars Inc, if I remember correctly) used a thick steel barrel at around 30" dia wrapped in spring steel to an overall thickness of around 2" had working pressures of 1500psi. Though quite how you would use steam at that pressure and temperature in a reciprocating engine I don't know!!!
We have a flash steam plant at the Steamboat Museum- SL Bat has a Stanley Steam Car boiler and Lifu burner. It has around 200 1/2" steel tubes in a 24" dia X 30" barrel supplying a 14hp Vosper-Thorneycroft compound engine.
Greg
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We seem to have digressed just a little from "Titanic" to an exposition on semantics by members of the dirty boilersuit brigade. How did that happen? I'm sure that there must be other web sites where Impulse turbines versus reaction ones can be argued. Steam is steam as far as most of us are concerned. Normal, flash, superheated or just the stuff coming out of a kettle spout is enough.
GIVE IT A REST for goodness sake! Either that, or take it somewhere else.
Nothing against the engineering fraternity, but really, is this the place for all that? BY.
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Forgive me Bryan, but are you not the author of one of the longest posts on the forum regarding your experiences and exploits while at sea- but this is a model boat forum, not an online memoir?
I read your posts, not always understanding what you write- not always wishing to- yet I understand your experiences bring aspects of the hobby to life for modellers that may never have even been on a boat, yet alone to sea for any period of time.
Perhaps you could be gracious enough to realise that not everyone is interested in you, yet we don't tell you so (before now).
Best of regards and no hard feelings,
Greg
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Forgive me Bryan, but are you not the author of one of the longest posts on the forum regarding your experiences and exploits while at sea- but this is a model boat forum, not an online memoir?
I read your posts, not always understanding what you write- not always wishing to- yet I understand your experiences bring aspects of the hobby to life for modellers that may never have even been on a boat, yet alone to sea for any period of time.
Perhaps you could be gracious enough to realise that not everyone is interested in you, yet we don't tell you so (before now).
Best of regards and no hard feelings,
Greg
Point taken. Put it down to an age related moment. Sorry.
But if you can't understand what I'm writing about then perhaps I should just quit now instead of befuddling others.
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Point taken. Put it down to an age related moment. Sorry.
But if you can't understand what I'm writing about then perhaps I should just quit now instead of befuddling others.
Apology accepted :-))
If we understood everything we would never ask questions- as I said I sometimes feel I don't wish to understand, feeling that an understanding would not enlighten me in any way- a little knowlege and all that, though perhaps also an arrogance on my part.
Now that is not to say that 100, 200, 300 people havn't read your posts and have gone on to research some little snippet of information or anacdote, perhaps knowing freinds or relatives in similar situations that never talk about thier experiences, whatever, there are many people, including myself, that look forward to your postings and I sincerely hope you don't stop any time soon.
Greg
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Bryan,
As a fully paid up deep-sea member of the Dirty Boiler Suit Divinity I can only extend my sympathy to you in your unenlightened condition which prevents you appreciating the true glory of steam.
On the other hand, as the best story-teller on the forum bar none, I suggest that you ignore any tetchy lake paddler's comments and carry on regardless. :-))
Barry M
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Bryan does make a valid point in that threads do go off the original subject, and this is not something I would even attempt to have an answer for.
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Greg 24900 people can't be wrong? Thats how many have read and most probably enjoyed Bryans post's
I think only "name that ship" or "name that part" are more popular. It is far more lucid and relates more
to ships and crews and other things nautical than some of the dross subjects that get created.
Geoff
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Would you mind not putting words in my mouth- I havn't said Bryan has no right posting what he does, I havn't said that 24900 people are wrong (though that is viewings and not the total of people that have read it). However Bryan did say we had no right to be posting about steam on here- something for which he apologised when I pointed it out. As far as I'm concerned that's the end of it, and long may BY continue to let us revel in his past, as long as he allows other members to revel in what they are interested in.
Oh, and BarryM- SY Gondola is a screw steamer, not paddle %)
Greg
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Oh, and BarryM- SY Gondola is a screw steamer, not paddle
Greg
Aye, I know that Greg - but I wasn't referring to the vessel. :P :P :kiss:
Barry M
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:P <*< >>:-(
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Bryan,
As a fully paid up deep-sea member of the Dirty Boiler Suit Divinity I can only extend my sympathy to you in your unenlightened condition which prevents you appreciating the true glory of steam.
On the other hand, as the best story-teller on the forum bar none, I suggest that you ignore any tetchy lake paddler's comments and carry on regardless. :-))
Barry M
Sir, I take umbrage at your slur! UMBRAGE d'you hear! "Srory-teller"? A simple STORY TELLER!. How dare you .Sir. Calling a Diarist a simple "story-teller" is akin to calling Ms.Rawlings an Historian! From your steam shrouded, snow bedecked enclave in "Wee-Frees" land, you no doubt feel immune to any sort of retribution. Not so.
Over the past millenium, we south of Carters Bar have been deluged with LIES. Particularly regarding the excellence of "Scottish" (should be "Scotch") education system. And now you, dear Sir, have proven the lie. For all your titles and ascendancy into the upper echelons of "Clankieism" it is evident that the teaching of our common language was quite remiss, Sir.
Your slur on my verspicacty is an outrage....I fear I should have to take to my bed.
Having said that, thank you. Bryan.
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Now, now, Bryan. Don't forget that under the terms agreed after the Battle of the Standard, all north of the Tyne is Scotland. The Deep Soothers have been ignoring this fact since the ink dried.
I don't know who this Ms Rawlings is, why you are retiring to bed or what you will be doing with your "versicacty" but are the three linked? %)
The Public must be told. :kiss:
Barry M
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Although I've tried to both understand and follow the ORIGINAL title of this topic, where on earth do the latest posts of this thread relate?
Just a thought really, no convoluted explanations neccessary .
{:-{ {:-{
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Tut-Tut Barry you dont know Ms rawlings - would it give you a clue if you put JK in front of her name.
And whilst we are on about kingdoms don't forget that at one time the ancient kingdom of Northumbria stretched
from York to Edinburgh so stuff you getting Berwick - we want Edinburgh back!!
Geoff
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tt1 - I'll give you a completely unconvoluted clue. Look at the title of this Forum! %%
Pugwash - Sorry, Battle of the Standard was after Northumbria was annexed by Scotland. Thus all bets are off except that we would like Berwick-on-Tweed back and I'm not sure that Ms Rawlings would benefit by the addition of 'JK' but Ms Rowling might. <*<
Right, now let's get back to Titanic.
Regards,
Barry M
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tt1 - I'll give you a completely unconvoluted clue. Look at the title of this Forum! %%
Pugwash - Sorry, Battle of the Standard was after Northumbria was annexed by Scotland. Thus all bets are off except that we would like Berwick-on-Tweed back and I'm not sure that Ms Rawlings would benefit by the addition of 'JK' but Ms Rowling might. <*<
Right, now let's get back to Titanic.
Regards,
Barry M
Barry and Geoff:- Honestly, I put "Rawlings" as the name sort of realising that you'd gather the real name, but I tend not to use real names in case I'm accused of character assassination. Bryan.
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As I was largely responsible for wresting this thread away from its original topic - for which I can only add my heartfelt and deep regret - I would also like to add my two-penn'orth to this further digression.
Although I am happy to leave the character of the said Ms Rowling utterly unassassinated, that's more than I can say about the bespectacled little twerp who has earned enough royalties to ensure the survival of every preserved vessel in Western Europe! So come on Harry. Use a bit of your magic to bring a bit of light into the gloomy underworld of we poor Dirty Boiler Suited muggles.
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With reference to earlier comments about super heated steam, when I was an apprenticed engine fitter in H M Dkyd Chatham, I was taught it was a gas, because it was so hot and no water saturation in it. In fact it was known to be very dangerous if a joint leaked because the leak was invisible and would cut a mans leg off quite easily and accidents like this did occur in the RN. Wet steam was taught as having water droplts in suspension and dry steam had no water droplets in suspension. But this was 44 years ago when I was doing my City and Guilds Technicion part one exam at Chatham Apprentice training college, which used to be St Mary's Barracks and the original home of HMS Fisguard, artificers training centre, it was moved at outbreak of war to Cornwall, because of the fear of German bombing raids.
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At the time of the Titanic disaster there was still a lot of sailing square riggers sailing around the world. A lot of seamen, in steam ships, from Masters to a/b's were trained in sail. Some of the helm orders given in those days related to the rudder tiller bar. ( the helm). So to alter course to Port, the order was given as Starboard Helm, I live in Amlwch Port on Anglesey and just outside the harbour is a small rock island called East Mouse at the bottom of which lies the wreck of the SS Dakota. She was outward bound from Liverpool when a northerly gale cought her as she was passing Amlwch and was blown towards a lee shore, the north coast of Anglesey. The old master had been trained in sail but the helmsman was trained in steam. The Master called for Port Helm, expecting his ship to turn to starboard. but it didn't. The helmsman put the wheel over to Port and the ship ran up onto the East Mouse rock, breaking her back and sinking between the Mouse and the coast of Anglesey. Some blamed the Master and some blamed the Helmsman and some said it was wrecked on purpose for the insurance, nobody knows. I just wonder if Capt Smith had made the same mistake out of the habit of a lifetime, who knows? After saying all that I probably should add ALLEGEDLY and I COULD BE WRONG to prevent a torrent of abuse from those in the know. regards Geoff C. PS. Has anyone checked Capt. Smith's employment history, did he start as a boy in sail?
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With reference to earlier comments about super heated steam, when I was an apprenticed engine fitter in H M Dkyd Chatham, I was taught it was a gas, because it was so hot and no water saturation in it. In fact it was known to be very dangerous if a joint leaked because the leak was invisible and would cut a mans leg off quite easily and accidents like this did occur in the RN. Wet steam was taught as having water droplts in suspension and dry steam had no water droplets in suspension. But this was 44 years ago when I was doing my City and Guilds Technicion part one exam at Chatham Apprentice training college, which used to be St Mary's Barracks and the original home of HMS Fisguard, artificers training centre, it was moved at outbreak of war to Cornwall, because of the fear of German bombing raids.
http://www.devonheritage.org/Places/Plymouth/CiviliancasualtiesofthebombingofTorpoint.htm
Out of the frying pan eh?
I joined up at Fisgard Sept 1959
Ned
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Read www.oldsaltblog.com on Google, click on" sea stories," then click "critique" and search for "Titanic" then article "Did a Steering Error Sink the Titanic". Geoff C.
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Hi netleyned, I see from your comment you was a boy art, which branch was you in, my old man was an ERA. I lived in Torpoint from 1980 to 1985, an I remember seeing the boy arts in uniform running like hell at night to get back to barracks on time, unlike the Rayliegh mob who sauntered along out of rig and with no cares in the world. You guys were the last professionals left in the ANDREW.
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Captain Smith was trained in sail and had commanded a square rigger (LIZZIE FENNELL)! But whatever happened that night, Captain Smith certainly did not make any msitakes with helm orders for the simple reason that he was not on the bridge when the ship hit the iceberg! Neither did 2nd officer Ligthtoller know what happened regarding helm order because he was off watch and in his cabin. I really don't know why this goes on and on - the answer will never be known!
I am still convinced that it has been brought up again merely as publicity for the novel which is, after all, fiction anyway!
Bob
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Hi netleyned, I see from your comment you was a boy art, which branch was you in, my old man was an ERA. I lived in Torpoint from 1980 to 1985, an I remember seeing the boy arts in uniform running like hell at night to get back to barracks on time, unlike the Rayliegh mob who sauntered along out of rig and with no cares in the world. You guys were the last professionals left in the ANDREW.
I joined to be a Shipwright but the powers that be decided what you were best at.
I ended up in the Radio Electrical Branch which later became the Weapons electrical branch
Now I believe it is all user/maintainer
The Battle Class were a good looking ship as you told Pugwash
Yours Aye
Ned
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Looks like two subjects at once here, I suppose it saves space elsewhere. Regards Geoff.
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Re: Was the wheel turned the wrong way - who knows!! The sad fact is that if the Titanic helmsman had not turned the wheel at all it would have made an awful mess of the bows by hitting the iceberg head on, but would, in all probability, have stayed afloat.
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Titanic Lives!
http://www.bbc.co.uk/news/science-environment-11926932
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Rusticles?? Aren't they made by Kelloggs? ;D
Barry M
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Hi Netleynd,
Yes it is all user/maintainers now, what were called diluties in the naval bases during the war. Perhaps that is part of the problem there now, no trained professional tradesmen. As my old man used to say jack of all trades master of none.