UK’s biggest warship suffers propeller shaft damage off south coast after setting sail for US

[WindyWindyWindy]

Do merchant ships do this a year after launch?

Couldn't they just get the Koreans to build an extra long 700m one and fly typhoons off it?

 

[Corona Mia]

My apologies for teasing.
But shouldn’t this thread be on the Motor Boat Forum??

 

[Bilgediver]

That’s what I am thinking, too. It makes sense.

The only reason that I can think of for giving the afterbody the form that it has, is fuel efficiency.

I am not sure of that heavy P bracket on the end of a relatively light hull tubing extension is normal Most commercial ships have a heavy structure built aft to the propeller boss. A bit of a job to get to the aft SKF coupling and have to decouple the one or both further forard as the dock might restrict how much can stick out . they might get lucky and the coupling is undamaged and sitting in the hull waiting for the grease guns.

 

[Bilgediver]

Do merchant ships do this a year after launch?

Would get the sack and a DR in the records

 

[jamie N]

Pathetic engineering!
Look at it like this, the shaft's transmitting 48Khp on a ship displacing 65k tonnes = 0.74hp/tonne.
Double it if you like for the 2nd shaft, but that's the spare in my eyes.
My Folkboat has a power to weight ratio of 3hp/tonne, from an Italian engine that I fitted myself, and as I've an outboard for getting around the marina, my 'spare' (Honda 2.3) outperforms the POW's even with a 0.77hp/tonne.
Mines been across the Pentland Firth more often, is far more manoeuvrable, and I get my own cabin.

 

[Bouba]

Pathetic engineering!
Look at it like this, the shaft's transmitting 48Khp on a ship displacing 65k tonnes = 0.74hp/tonne.
Double it if you like for the 2nd shaft, but that's the spare in my eyes.
My Folkboat has a power to weight ratio of 3hp/tonne, from an Italian engine that I fitted myself, and as I've an outboard for getting around the marina, my 'spare' (Honda 2.3) outperforms the POW's even with a 0.77hp/tonne.
Mines been across the Pentland Firth more often, is far more manoeuvrable, and I get my own cabin.

You forget Prince of Wales has nearly 900 feet of waterline...so you only need to find its displacement speed

 

[jamie N]

You forget Prince of Wales has nearly 900 feet of waterline...so you only need to find its displacement speed

That depends on the tug towing it doesn't it?

 

[Biggles Wader]

Does the RN do "shock testing" of its new ships like the USA does? Battle simulations with near miss explosions are done as if for real to ensure the ships can still function, especially the prop/ rudder areas.

 

[Bouba]

Does the RN do "shock testing" of its new ships like the USA does? Battle simulations with near miss explosions are done as if for real to ensure the ships can still function, especially the prop/ rudder areas.

I don’t think so....the USN build their ships to a naval standard...whereas most European warships are built to commercial standard...so, similar sized would see American ships heavier

 

[Kukri]

Do merchant ships do this a year after launch?

Couldn't they just get the Koreans to build an extra long 700m one and fly typhoons off it?

Back in the Dawn of Time, in the Sixties and Seventies of the last century, there was a thing called the Guarantee Docking, roughly a year after a new ship had been delivered, in which the ship was dry docked and the builders put right those items on the Defect List which they agreed were their fault, and the owner got to renew the antifouling paint and to do the bits that he could not get the yard to spring for.

This dropped out of use because it was expensive to take a new ship out of service and it was usually hard to find a convenient dry dock. It was replaced with a diving survey and the antifouling was better.

These days, we expect to dry dock every thirty months. Every other dry docking is a Special Survey in which the Classification Society have a proper look at the ship.

We expect our ships to be about 99.8% reliable, and they generally are.

 

[Bouba]

Back in the Dawn of Time, in the Sixties and Seventies of the last century, there was a thing called the Guarantee Docking, roughly a year after a new ship had been delivered, in which the ship was dry docked and the builders put right those items on the Defect List which they agreed were their fault, and the owner got to renew the antifouling paint.

This dropped out of use because it was expensive to take a new ship out of service and it was usually hard to find a convenient dry dock. It was replaced with a diving survey and the antifouling was better.

These days, we expect to dry dock every thirty months. Every other dry docking is a Special Survey in which the Classification Society have a proper look at the ship.

We expect our ships to be about 99.8% reliable, and they generally are.

What would you put the reliability down to...example...would it be a single screw with a huge displacement very slow turning engine, the crew, the build quality etc....and how would you compare it to a warship ?
To me, a warship is more akin to a pleasure motorboat...no cargo except the crew, very high performance which is used often, lots of complicated electronics...and the reliability is almost the same...ie, always something and it’s always expensive

 

[jamie N]

Kukri; your reliability figures are interesting, as just today I was chatting with 'someone' about ROV reliability. For a 'permanent/installed' system, it was expected to have 97% reliability, and for a mobile system, moving from vessel to vessel and contract to contract, it was 95%.
Of course the 2 aren't similar at all, apples and pears if you like, but these type of stats can be overlooked by folk outside of the industries involved.
Back in the day we did have an ROV system with 35% downtime, before the crew were 'reassigned' to rival companies.
Just a thought, I wonder whether any of them joined the RN?

 

[Kukri]

What would you put the reliability down to...example...would it be a single screw with a huge displacement very slow turning engine, the crew, the build quality etc....and how would you compare it to a warship ?
To me, a warship is more akin to a pleasure motorboat...no cargo except the crew, very high performance which is used often, lots of complicated electronics...and the reliability is almost the same...ie, always something and it’s always expensive

I will start by quoting what is generally known as Holt’s Law. This is named after the great Victorian engineering and commercial genius, Alfred Holt, of Liverpool, founder of the Blue Funnel Line, and it comes from a lecture that he gave in 1878 to the Institute of Civil Engineers, titled “A Review of the Progress of Steam Shipping in the Past Quarter Century”

It is found that anything that can go wrong at sea generally does go wrong sooner or later.


That is Holt’s Law. It is the ancestor of Murphy’s Law, and it has three corollaries:

Sufficient stress can hardly be laid on the advantages of simplicity.

The human factor cannot be safely neglected in planning machinery.

It is almost as bad to have too many parts as too few.

Holt was, as was usual amongst the Great Engineers, a driven genius, a man with a sound head for business, and deeply religious.

We can pretty much say that successful steam shipping that did not depend on Government subsidy starts with Holt’s first three ships in 1862.

He disagreed strongly with Samuel Plimsoll because he thought that a system of regulations would lead to cheating and to bad consequences. Had he lived long enough he would certainly have cited the insufficient lifeboats on the Titanic as an example of the bad effects of regulations - the Titanic had four more lifeboats than the Board of Trade regulations required…

Holt disapproved of insurance on the grounds that it made people careless, and his fleet was always uninsured until the 1960s.

 

[capnsensible]

Now that's fascinating stuff. Those early engineers certainly had vision.

 

[Bouba]

I will start by quoting what is generally known as Holt’s Law. This is named after the great Victorian engineering and commercial genius, Alfred Holt, of Liverpool, founder of the Blue Funnel Line, and it comes from a lecture that he gave in 1878 to the Institute of Civil Engineers, titled “A Review of the Progress of Steam Shipping in the Past Quarter Century”

It is found that anything that can go wrong at sea generally does go wrong sooner or later.


That is Holt’s Law. It is the ancestor of Murphy’s Law, and it has three corollaries:

Sufficient stress can hardly be laid on the advantages of simplicity.

The human factor cannot be safely neglected in planning machinery.

It is almost as bad to have too many parts as too few.

Holt was, as was usual amongst the Great Engineers, a driven genius, a man with a sound head for business, and deeply religious.

We can pretty much say that successful steam shipping that did not depend on Government subsidy starts with Holt’s first three ships in 1862.

He disagreed strongly with Samuel Plimsoll because he thought that a system of regulations would lead to cheating and to bad consequences. Had he lived long enough he would certainly have cited the insufficient lifeboats on the Titanic as an example of the bad effects of regulations - the Titanic had four more lifeboats than the Board of Trade regulations required…

Holt disapproved of insurance on the grounds that it made people careless, and his fleet was always uninsured until the 1960s.

Thank you for that....what seems self evident always started with someone thinking outside the box

 

[capnsensible]

Adding to the more serious side of the thread, how about this

On 25 January 1999, six companies were invited to tender for the assessment phase of the project – Boeing, British Aerospace (BAe), Lockheed Martin, Marconi Electronic Systems, Raytheon and Thomson-CSF.[23] On 23 November 1999, the MoD awarded detailed assessment studies to two consortia, one led by BAe (renamed BAE Systems on 30 November 1999) and one led by Thomson-CSF (renamed Thales Group in 2000). The brief required up to six designs from each consortium with air-groups of thirty to forty Future Joint Combat Aircraft (FJCA). The contracts were split into phases; the first £5.9 million phase was for design assessment which would form part of the aircraft selection, while the second £23.5 million phase involved "risk reduction on the preferred carrier design option".[24]
In 2005 BMT announced it has tested 4 different CVF hull form models and assessed them for propulsion efficiency, maneuverability, seakeeping and noise signatures. It also investigated skeg length, rudder size, transom stern flaps and bulbous bow designs. The basic Delta concept went through many further iterations and development before the design was considered sufficiently mature by late 2006 for detailed cost estimates to be drawn up prior to ordering long-lead items.[25]

Offered also simply for interest.

 

[capnsensible]

BMT are these

BMT Group Ltd (previously British Maritime Technology) was established in 1985, from the merger of the UK's British Ship Research Association and National Maritime Institute, as an international multidisciplinary engineering, science and technology consultancy[1] offering services particularly in the defence and security, critical infrastructure, commercial shipping, and environment sectors. The company's heritage goes back to WWII.[2] BMT's head office is in London U.K.[3] BMT specialises in maritime engineering design, design support, risk and contract management. BMT provides services focused by geography, technology and/or market sector. It employs around 1,500 professionals operating from 47 offices across four continents, with primary bases in South America, Australia, Europe, North America and Asia-Pacific.[1] In August 2017, Sarah Kenny OBE was appointed as the company's Chief Executive Officer.[4] The company's annual turnover for the year 2019 was approx. £176m.[5]

 

[Kukri]

Starting with Holt’s Law and Corollaries everything on board a ship which is necessary for her safe operation has either been built under Classification Society survey or is made to Type Approved specifications. So there is a very great deal of standardisation.

In recent years we have been learning a lot from the civil aviation sector. We have and are standardising procedures for almost everything, with check lists.

To illustrate, from something I’m doing at this moment, two years ago one of our ships was alongside in Hong Kong and the crew moved the stores crane over the quay without checking with the shore crane operators and a gantry container crane (lift capacity 80 tons) moved up and clouted our ship’s stores crane (capacity 5 tons..) and bent it. Nobody was hurt and the shore crane was not damaged.

So my colleague who is our DPA (Dedicated Person Ashore)* wrote a procedure to stop this happening again and just now he is fit to be tied and is drafting a “We Fail To Understand letter” by email, because a sister ship has just done the very same thing in Melbourne and the Australian Maritime Safety Agency want to know what we are going to do about it.

* The DPA was brought in under the International Safety Management Code in 1979; he is the person responsible for the safe operation of a fleet and by law he must have immediate free access to the Chief Executive.

 

[Kukri]

Thank you for that....what seems self evident always started with someone thinking outside the box

I share my sons’ pleasure in watching Elon Musk show an interviewer round the SpaceX rocket building facilities because he keeps coming up with the corollaries to Holt’s Law.

Musk wants to put people on Mars.
Holt wanted to carry cargo from London to Shanghai and vice versa at a profit, to a fixed schedule using unsubsidised iron steam ships. This was about as absurd in the 1850s as life on Mars is now. His secret weapon was that he was a trained railway engineer and he had just invented the first successful high pressure compound marine steam engine.

Shades of “full flow, staged combustion…” both are aimed at extracting maximum forward motion from a given amount of fuel…

 

[Bouba]

I share my sons’ pleasure in watching Elon Musk show an interviewer round the SpaceX rocket building facilities because he keeps coming up with the corollaries to Holt’s Law.

Musk wants to put people on Mars.
Holt wanted to carry cargo from London to Shanghai and vice versa at a profit, to a fixed schedule using unsubsidised iron steam ships. This was about as absurd in the 1850s as life on Mars is now. His secret weapon was that he was a trained railway engineer and he had just invented the first successful high pressure compound marine steam engine.

True, Musk is always quoting that sort of thing...and he lives by it...and it drives people on the Tesla forum around the bend...because he is always removing hardware from the car...to simplify it... and everyone else thinks, no...it works don’t touch it??