Concordia News: Please Post Here

[chengkp75]

Cheng ... does the info you have given on ship rudder commands apply to every ship ? i am thinking of those with fixed rudders as against those ships with Azipods and those with the extra bits fitted to the rudder to help turning .. the name escapes me of that one.

 

Sid;

 

All steering systems have some delay between the helm position (which is a go-kart sized steering wheel) and the position of the steering mechanism, whether rudder or pod. This is due to translating electrical signal from the helm stand to hydraulic signal at the rudder/pod. The 30 second from hard over to hard over is a maximum allowed, regardless of type, and many do better than that.

 

All ships do not respond instantaneously to rudder commands due to the momentum of a huge weight moving in one direction, and trying to move it in another. As the Skipper will confirm, there will always be a few seconds of heartburn before a ship starts to turn, but once it does, the rate of turn will increase the longer the helm is at a given position.

 

The one distinct advantage that pods have over a propeller/rudder combination comes in construction. Pods cost less than propulsion motors, shafting, propellers, rudders, and steering motors and thrusters. Since the pods act as propulsion, steering, and thrusters, you save money on capital expense.

 

Pods will provide direct thrust to steer the ship, while rudders create a force of water against one side of the rudder forcing the stern of the ship the other direction. Direct thrust is definitely more efficient at slow speed, like docking, but at sea speed, the difference is reduced.

 

The "extra bits" on a rudder are generally called a "Becker rudder", and is a trim tab on the trailing edge of the rudder. This creates an airfoil shape to the rudder, and actually creates "lift" across the rudder, increasing the force the rudder exerts on the ship. Becker rudders are designed to increase turning effort at slow speed, as standard rudders generally lose effect below 4-5 knots (that's why they install thrusters for docking, as the rudder no longer gives any steering effect), but with any water flow past the Becker rudder at all, there will be some lift. Beckers will also increase the turning effect at high speed, generally with disasterous results: once the ship starts turning, it will turn quite rapidly, and the ship will heel alarmingly. The Norwegian Sky had the helm put hard over at 20knots coming into Vancouver, and the ship heeled over 35-40*. There were virtually no glassware or dishes unbroken onboard, and over 100 passengers were taken to hospital when the ship docked.

 

Not sure if the Concordia has Becker rudders, but I would have thought that would have been mentioned in the report, but there is still a delay between helm command and ship turning, no matter what type of steering is involved.

[clive and anne]

Cheng

Thank you so much for all your invaluable input to this thread. You will be sadly missed at the time of most interest such as the parbuckle.

Have a safe trip and we look forward to you coming back when your "tour of duty ends.

Goodbye and good luck

[chengkp75]

Cheng

Thank you so much for all your invaluable input to this thread. You will be sadly missed at the time of most interest such as the parbuckle.

Have a safe trip and we look forward to you coming back when your "tour of duty ends.

Goodbye and good luck

 

Thanks;

 

I tried to stay home, but the boss (my wife of 37 years who has put up with my sailing all that time, and raising 3 boys) says we've got to pay the bills somehow! Not to mention Tom, my relief on the ship, who is waiting to get home to his family. I'll be thinking of all of you that I've met here on this most interesting thread. I've archived my Triumph and Grandeur threads, but I hope this one is still alive when I get back.

[chengkp75]

I am hoping for maybe some cams mounted on the wreck' date=' something like they do when they sink a vessel for a reef.

 

Chief your a great addition here, you word things much better then I do and you have more up to date details on active sailings that I don't since I am ashore and working from there!

 

Which school did you go to?

 

 

AKK[/quote']

 

Hey, Skipper, somehow missed your post this morning. From my screen name, I'm a Kings Point grad, class of 1975. How about you?

[chengkp75]

Cheng

Thank you so much for all your invaluable input to this thread. You will be sadly missed at the time of most interest such as the parbuckle.

Have a safe trip and we look forward to you coming back when your "tour of duty ends.

Goodbye and good luck

 

Looking at your signature, I'll just have to top you, and say my first cruise was the QE2 in 1977. It took me until 2006 to get my wife back on another cruise, and now she's pestering me for more.

 

Another question. I see you did the Pride of America in 2008, which is when we lost the Pride of Aloha (along with my job there), and the Pride of Hawaii. I know those were difficult times for the company with regards to crew, would you mind giving me your impression?

[clive and anne]

Hi Cheng

It was a strange trip that one. It took 27 hours including stopovers, to get from Manchester to Honolulu. We stayed 3 nights in Honolulu and then flew to Maui to meet up with friends from California, then after 3 days we flew back to Honolulu to meet up with Pride of America. we sailed that night for.....Maui. Wonderful planning on my part.

The cruise was fine, much different than the British cruiselines. Basically the American ships have a much greater emphasis (and deck area) for gambling and not the same emphasis on the live theatre whereas the opposite applies on British ships. Also the American ships are much younger and larger than the british equivilant. We enjoyed our trip very much but as we get older we find that the air travel takes us much longer to recover from.

What a pity we don't know what ship you are on and we could follow you on AIS.

Bon Voyage my friend

[chengkp75]

Clive;

 

I hear you about air travel. Really gets old after a few decades!

 

Thanks for the interest. The ship is the Overseas Chinook, and tracking us will be almost as interesting as Micoperi M30! She is currently south of Puerto Rico, probably on the way back to the states. We are a shuttle tanker, which means that like the North Sea, instead of oil pipelines from the offshore oil fields, there is a floating production ship moored there, and we act as the pipeline, taking 300,000 barrels at a time to shore. The project is a couple years behind schedule (sound like the Concordia?), so we are only making trips to the rig (20 hours each way) every 3-4 weeks right now. Our company has built two shuttle tankers (the only ones in the US) for this field, and we are hoping to get production up to where at least one ship is on continual runs. Loads of anchor time off scenic places like Galveston, Lake Charles, Pascagoula, and other hotspots of scenic beauty.

[clive and anne]

Hi Cheng

If you would like my email address will send it in two halves to avoid spammers anne_cliveuk

[chengkp75]

Hi Cheng

If you would like my email address will send it in two halves to avoid spammers anne_cliveuk

 

Thanks for the offer, but the only e-mail available onboard is company with very limited personal (wife, kids). I will try to stay in touch with the process from afar.

[Tonka's Skipper]

Hey, Skipper, somehow missed your post this morning. From my screen name, I'm a Kings Point grad, class of 1975. How about you?

 

 

No problem, I just got back from a quick survey!

 

Kings Point............hmmm......I kind a guessed that from your handle...:rolleyes:

 

I went to the great institution under the bridge, across the western end of the sound from you.........SUNY Maritime 73'.:D

Edited July 31, 2013 by Tonka's Skipper

[sidari]

"which is a go-kart sized steering wheel"

 

Cheng .... Thanks for the info, i recall a documentary recently where they mentioned and showed the Becker Rudders but i could not recall the name for my earlier post.

 

With regard to the quote at the top we were lucky on two occasions to visit the bridge of the Ruby princess and saw the steering wheel size you mention.

[chengkp75]

"which is a go-kart sized steering wheel"

 

Cheng .... Thanks for the info, i recall a documentary recently where they mentioned and showed the Becker Rudders but i could not recall the name for my earlier post.

 

With regard to the quote at the top we were lucky on two occasions to visit the bridge of the Ruby princess and saw the steering wheel size you mention.

 

A go-kart is something that us conspicuous consumption Americans let our kids drive. It's a metal cage with small tires and a hopped-up lawn mower engine. Rite of passage for young males, driving around in a field fenced in by hay bales. You get to think you're an F-1 driver (Jackie Stewart) or Mario Andretti for us Americans.

[clive and anne]

Lone is about to dock in Livorno after sailing there overnight.

I wonder if that is to pick up the mysterious "Blister"

[clive and anne]

Lone has just left Livorno on the same track as she went there. Presumably she is returning to Giglio. I wonder what she has been loaded with. I would think, as she's doing 19 knots she may be back to Giglio by nightfall.

[lightman1984]

talk about a quick trip! I expected Lone to be up there for at least a day.

[Bearded Engineer]

Lone is about to dock in Livorno after sailing there overnight.

I wonder if that is to pick up the mysterious "Blister"

 

In his latest status report video on the parbuckling web site, the project manager, Nick Sloane, refered to it as a "blister tank" and said that at over 1000 tonnes it would be the largest item to be attached to the wreck. He also said it would give 6000 tonnes of bouyancy so it is more that a support structure, it must also be a cassion. It will be interesting to see what it looks like.

[clive and anne]

AIS say that Lone is due to arrive at Porto Stephano at 6pm. However they don't say whether its BST, GMT or what. I am guessing that it will be about 7pm BST. That should cover it LOL. Perhaps we will have to wait for the morning for it to arrive at Giglio. It should be interesting as this is due to go on the bow so we should have a good view.

[SomeBeach]

I emailed the company almost 2 weeks ago in hopes of getting an explanation as to what blister is and it's purpose. I see from Bearded's post, Mr Sloane somewhat addressed it.

I assured them that we would not pester them but did explain who we were and how actively we were following the salvage.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

I've been super drugged (knee replacement) since Monday. Tho I've been keeping up I don't want to post because my mind is a bit fuzzy. :D

What brought me on was to wish ChengKP a safe journey. We will look forward to your return.

[chengkp75]

From the infamously slow parbuckling site, while the graphic still shows P4 and P13 to be installed, the "flash news" line states that P4 was installed Tuesday, but no mention of P13, so I believe this is still onboard the Lone. The salvage master said the blister tank would be arriving onsite around 8 Aug, so I don't think that will be on the Lone now, and a 1000mt lift onto Lone would not have happened in a couple of hours.

[clive and anne]

Hi SB

Sorry to hear about your surgery, I hope it went well.

You see you disappeared for a few days and I lost Cheng lol.

Your post reminded me that I didn't receive an answer from Giglio News about that awful camera they have installed on the rocks.

Wishing you a speedy recovery and I will try not to lose any more of our experts.

[Tonka's Skipper]

From the infamously slow parbuckling site, while the graphic still shows P4 and P13 to be installed, the "flash news" line states that P4 was installed Tuesday, but no mention of P13, so I believe this is still onboard the Lone. The salvage master said the blister tank would be arriving onsite around 8 Aug, so I don't think that will be on the Lone now, and a 1000mt lift onto Lone would not have happened in a couple of hours.

 

 

I agree, it would take much more then 2 hours to rig, lift, shift compensating ballast back and forth as it is positioned onboard and then tie it down,etc.

 

AKK

[Mike.Minh]

AIS say that Lone is due to arrive at Porto Stephano at 6pm. However they don't say whether its BST, GMT or what.

 

GMT doesn't have an officially defined precision in the sub second level, but its successor UTC (Universal Time Coordinated) has and is used or referred to by AIS. For us here GMT=UTC will do, I guess.

[SomeBeach]

The article in this link doesn't go into the "why" it is so imperative Concordia be righted by Sept. We have probably discussed in greater detail the reasons officials bring it up from various articles released, ie: grinding of the submerged portion of the ship.

http://www.upi.com/Top_News/World-News/2013/08/01/Grounded-ship-Costa-Concordia-must-be-righted-by-winter-official-says/UPI-75521375383988/

 

IMO, I believe it will just give people, especially the folks on Giglio, a greater hope that the elephant in the living will be gone by next year. ;)

[chengkp75]

The article in this link doesn't go into the "why" it is so imperative Concordia be righted by Sept. We have probably discussed in greater detail the reasons officials bring it up from various articles released, ie: grinding of the submerged portion of the ship.

http://www.upi.com/Top_News/World-News/2013/08/01/Grounded-ship-Costa-Concordia-must-be-righted-by-winter-official-says/UPI-75521375383988/

 

IMO, I believe it will just give people, especially the folks on Giglio, a greater hope that the elephant in the living will be gone by next year. ;)

 

I saw a somewhat more complete report on the Giglio home site (given a painful translation). It sounds to me like more complaints about the schedule slipping, and everyone's concerns that Costa will default on paying for completion. I still don't think she will be moved before spring, unless there is an unusual weather pattern that allows a lot of work after parbuckling. As all of the starboard caissons will be welded underwater, and no one knows how much deformation there is on that side, this will probably go much slower than the port caissons.

[sidari]

Hi Cheng .... Why would the Caissons have to be welded underwater once the ship is upright ? will they not be bolted to the steel girders that will be welded to the side of the ship?