Jump to content
Cruise Critic Community
boscobeans

Infinity lines may be caught in Bow Thruster.

Recommended Posts

47 minutes ago, c-legs said:

I beg to differ....A ship cannot sail from a US port, and return to the same port without a stop in a foreign port, ( in this case, the Bahamas, the ever popular cal;l that allows the shorties to operate these types of sailings.

My opinion only.

 

Generally correct.  However I believe they can get waivers in the event of a mechanical problem.  Case in point - Grand Princess in 2016 was coming from Hawaii back to San Francisco via Ensenada.  A day out they noticed a tender door was broken, so they hightailed it back to Honolulu and flew all the passengers home.

 

Edited by abbydancer

Share this post


Link to post
Share on other sites
5 hours ago, Timeforvaca said:

We’re onboard. Still in port 5.5 hours after we were supposed to sail.  Casino closed so obviously a serious situation. Nothing communicated to passengers. Hoping it gets resolved!!

 

Staying in port an extra 5.5 hours without any explanation to passengers?

 

Very poor communication by ship management.

Share this post


Link to post
Share on other sites

Not a common occurrence, but not unknown either.  Miscommunication between the bow mooring station and the bridge, not notifying bridge that lines were in the water.  Synthetic lines like those used on cruise ships will not damage a propeller, but in some cases will heat up and melt from the rotating propeller, and this can get stuck in the propeller shaft seal that keeps the oil in the thruster gearbox.  Won't know about that until they test it a few times, and see if it's leaking oil.

 

Cruise ships are designed for underwater surveys in the intermediate periods (every 2.5 years) between dry dockings, early in their life (less than 15 years old), so the gratings on the thrusters are bolted and hinged to allow diver access.  Typically, they will use an air-powered grinder to remove the wound up mooring line from the thruster.

 

Yes, they could have operated without the one thruster, if it was only one thruster, but if there was a significant "tail" hanging, it could have fouled another thruster the next time they are used.

 

And, yes, CBP often grants waivers of the PVSA for a cruise with no foreign port, due to weather or mechanical issues.  And, if this had been a "cruise to nowhere", with only the embarkation and debarkation ports, that isn't a violation of PVSA, they are still allowed, but only with crew who have work visas to the US, but again CBP grants waivers for weather and mechanical issues.

Share this post


Link to post
Share on other sites
53 minutes ago, chengkp75 said:

...Synthetic lines like those used on cruise ships will not damage a propeller, but in some cases will heat up and melt from the rotating propeller, and this can get stuck in the propeller shaft seal that keeps the oil in the thruster gearbox.  Won't know about that until they test it a few times, and see if it's leaking oil....

 

Is it more likely that water will leak into the gear box instead of oil into the water?  I suspect we'll never know if the Infinity is operating with two instead of three bow thrusters.

Edited by ipeeinthepool

Share this post


Link to post
Share on other sites
1 hour ago, chengkp75 said:

Not a common occurrence, but not unknown either.  Miscommunication between the bow mooring station and the bridge, not notifying bridge that lines were in the water.  Synthetic lines like those used on cruise ships will not damage a propeller, but in some cases will heat up and melt from the rotating propeller, and this can get stuck in the propeller shaft seal that keeps the oil in the thruster gearbox.  Won't know about that until they test it a few times, and see if it's leaking oil.

 

 

I watched the video of the line getting tangled.    It appeared that there were still several lines not yet "on the Deck".   An officer popped out onto the side bridge only after the line got caught in thruster, then bolted back in.   Could it be that the line handlers called "lines away" and the bridge took that as "lines on deck" and engaged the bow thrusters too soon?   Seems like proper procedure would be for an officer to be out on the side bridge to verify all lines on deck before giving the okay to engage bow thrusters.

 

I'm just curious on what proper communications and procedure is here.   In my old line of work, communications and adherence to procedure were mission critical.   I'd love for anyone with large vessel experience to run down whats proper and give their views.

 

(PS....Isn't it a local law in Key West that all ships need to be gone from the dock before sunset, as that is a key sun watching point?   Not sure if true, but seem to recall something like this the one time we docked in Key West.   If true that only adds to the ships woes.)

 

Thanks.

Edited by zdad59

Share this post


Link to post
Share on other sites
2 hours ago, ipeeinthepool said:

 

Is it more likely that water will leak into the gear box instead of oil into the water?  I suspect we'll never know if the Infinity is operating with two instead of three bow thrusters.

No, propeller shaft seals are designed with a head tank to provide sufficient pressure to overcome the height of the water, so you get oil leaking out.  This is why these seals have multiple seals in a row, and as of recently, you have to use an "environmentally friendly" oil in thruster gearboxes, azipod bearings, and propeller stern tube bearings.

Share this post


Link to post
Share on other sites
2 minutes ago, chengkp75 said:

No, propeller shaft seals are designed with a head tank to provide sufficient pressure to overcome the height of the water, so you get oil leaking out.  This is why these seals have multiple seals in a row, and as of recently, you have to use an "environmentally friendly" oil in thruster gearboxes, azipod bearings, and propeller stern tube bearings.

 

Thanks for the design details.

Share this post


Link to post
Share on other sites
1 hour ago, zdad59 said:

 

I watched the video of the line getting tangled.    It appeared that there were still several lines not yet "on the Deck".   An officer popped out onto the side bridge only after the line got caught in thruster, then bolted back in.   Could it be that the line handlers called "lines away" and the bridge took that as "lines on deck" and engaged the bow thrusters too soon?   Seems like proper procedure would be for an officer to be out on the side bridge to verify all lines on deck before giving the okay to engage bow thrusters.

 

I'm just curious on what proper communications and procedure is here.   In my old line of work, communications and adherence to procedure were mission critical.   I'd love for anyone with large vessel experience to run down whats proper and give their views.

 

(PS....Isn't it a local law in Key West that all ships need to be gone from the dock before sunset, as that is a key sun watching point?   Not sure if true, but seem to recall something like this the one time we docked in Key West.   If true that only adds to the ships woes.)

 

Thanks.

There should have been a deck officer on the mooring observation platform (that platform that folds out from the bow in port) to observe the undocking procedure.  This gives a far better vantage point than the bridge wings.  The ship takes no communication from the line handlers on shore, and they have no authority.  That deck officer should have been on the platform all the time, as that is the only way the crew operating the ship's winches know when to slack down a line to let the line handlers throw it off the bitt, or when to start hoisting the line in, and he is the one in charge of these winches.  It is industry standard for this officer to announce "lines in the water", and "all lines clear of the water" to alert the bridge as to when they can run the thrusters, as well as the main propellers, which are also subject to this kind of fouling.  Any Captain worth his salt would not start thrusters (actually they are always running when starting to undock, just with zero pitch, so that there is no suction of water one way or the other) thrusting until he had heard the "all lines clear forward" report.  Now, the pilot may have ordered the thrusters to thrust, but again, the pilot is merely an advisor, and does not actually operate any control, he merely passes orders to the bridge crew.  The pilot has usually been "given the conn" (the authority to give orders to the bridge crew) by the Captain, but the Captain has the right and authority to countermand any order the pilot gives at any time.  So, there may not have been a proper report from the bow, there could have been a garbled report, or the pilot could have ordered something and the bridge crew complied before the Captain could determine if it was safe.

Share this post


Link to post
Share on other sites
9 hours ago, chengkp75 said:

Not a common occurrence, but not unknown either.  Miscommunication between the bow mooring station and the bridge, not notifying bridge that lines were in the water.  Synthetic lines like those used on cruise ships will not damage a propeller, but in some cases will heat up and melt from the rotating propeller, and this can get stuck in the propeller shaft seal that keeps the oil in the thruster gearbox.  Won't know about that until they test it a few times, and see if it's leaking oil.

 

Cruise ships are designed for underwater surveys in the intermediate periods (every 2.5 years) between dry dockings, early in their life (less than 15 years old), so the gratings on the thrusters are bolted and hinged to allow diver access.  Typically, they will use an air-powered grinder to remove the wound up mooring line from the thruster.

 

Yes, they could have operated without the one thruster, if it was only one thruster, but if there was a significant "tail" hanging, it could have fouled another thruster the next time they are used.

 

And, yes, CBP often grants waivers of the PVSA for a cruise with no foreign port, due to weather or mechanical issues.  And, if this had been a "cruise to nowhere", with only the embarkation and debarkation ports, that isn't a violation of PVSA, they are still allowed, but only with crew who have work visas to the US, but again CBP grants waivers for weather and mechanical issues.

With the rush for better efficiency cutting through the water using air bubbles and new bow designs (or recycled), kind of funny that grates would cover the big holes (to the water anyway) on the side of the hulls  and as drag when moving forward.

Share this post


Link to post
Share on other sites

I was looking this morning and Infinity is "steaming" toward Nassau and is scheduled to arrive on time tomorrow at 06:00

 

 

Share this post


Link to post
Share on other sites
1 hour ago, longhorn2004 said:

With the rush for better efficiency cutting through the water using air bubbles and new bow designs (or recycled), kind of funny that grates would cover the big holes (to the water anyway) on the side of the hulls  and as drag when moving forward.

The grates are inside the tunnel, not protruding outside the hull.  Because the "holes" in the hull that are the openings for the thruster tunnels are canted with regards to the length of the ship (the bow curves inward here, so the opening partially faces forward), these opening present the largest amount of drag and the gratings, if well designed (mostly horizontal bars), can act as flow directors to improve drag.

 

And regardless of what is said about the "new" bow designs reducing drag, that isn't quite so.  The "inverted" bow merely increases the waterline length in relation to the overall length, and a longer waterline length allows a greater "hull" speed (the speed of maximum efficiency) for a given horsepower.  The inverted bow, however, does not provide the reserve buoyancy that a traditional flared bow does, so it won't ride up and over seas like a flared bow, but will tend to dig in and cut through seas, creating a "wetter ride" forward (more chance of seas being shipped over the bow).

Share this post


Link to post
Share on other sites
14 minutes ago, chengkp75 said:

The grates are inside the tunnel, not protruding outside the hull.  Because the "holes" in the hull that are the openings for the thruster tunnels are canted with regards to the length of the ship (the bow curves inward here, so the opening partially faces forward), these opening present the largest amount of drag and the gratings, if well designed (mostly horizontal bars), can act as flow directors to improve drag.

 

And regardless of what is said about the "new" bow designs reducing drag, that isn't quite so.  The "inverted" bow merely increases the waterline length in relation to the overall length, and a longer waterline length allows a greater "hull" speed (the speed of maximum efficiency) for a given horsepower.  The inverted bow, however, does not provide the reserve buoyancy that a traditional flared bow does, so it won't ride up and over seas like a flared bow, but will tend to dig in and cut through seas, creating a "wetter ride" forward (more chance of seas being shipped over the bow).

 

I just stopped by to read about the particulars of this incident. Can't help but be awed by your knowledge of the subject, sir. Many thanks. 

Share this post


Link to post
Share on other sites

Chief.   A question.     Does a cruise ship have a cockpit recorder where folks can go back and reconstruct the events?    I’m super curious about what In the procedure failed here.   Was a bad call made by the officer on the mooring platform or did the captain or pilot hear the wrong thing and prematurely give the ok to engage the thrusters?

 

This would never happen on the Starship Enterprise. 

Share this post


Link to post
Share on other sites

Being a life-long sailor myself I can tell you the there are three types of boaters:

1) Those who have sucked-up a line on the thruster/prop

2) Those who are about to suck-up a line on the thruster/prop

3) Liars

 

LRGatorAction3.jpg

Edited by A Sixth?

Share this post


Link to post
Share on other sites
1 hour ago, zdad59 said:

Chief.   A question.     Does a cruise ship have a cockpit recorder where folks can go back and reconstruct the events?    I’m super curious about what In the procedure failed here.   Was a bad call made by the officer on the mooring platform or did the captain or pilot hear the wrong thing and prematurely give the ok to engage the thrusters?

 

This would never happen on the Starship Enterprise. 

Yes, there is a bridge data recorder (helm and engine commands, heading, speed, etc) and a voice recorder.  Typically, the data would not be retrieved for an incident like this, which is not considered to be a "major marine incident" (typically damages over $20k).  The voice recorder is what caught Schettino asking the engineers to confirm that the Concordia was flooding 3 compartments, and saying that if it was only two, then things were okay, but if it was three compartments, the ship was sinking, and this was hours before he decided to have the passengers report to muster stations.

 

This incident will be investigated internally, and bridge management practices and procedures adjusted accordingly.  It really is a minor incident.

Share this post


Link to post
Share on other sites
On 12/14/2018 at 10:34 PM, Timeforvaca said:

We’re onboard. Still in port 5.5 hours after we were supposed to sail.  Casino closed so obviously a serious situation. Nothing communicated to passengers. Hoping it gets resolved!!

There was an announcement initially from the cruise director. The Captain also spoke about it at the Captain's Club gathering

 

Share this post


Link to post
Share on other sites
On 12/15/2018 at 6:09 PM, chengkp75 said:

Yes, there is a bridge data recorder (helm and engine commands, heading, speed, etc) and a voice recorder.  Typically, the data would not be retrieved for an incident like this, which is not considered to be a "major marine incident" (typically damages over $20k).  The voice recorder is what caught Schettino asking the engineers to confirm that the Concordia was flooding 3 compartments, and saying that if it was only two, then things were okay, but if it was three compartments, the ship was sinking, and this was hours before he decided to have the passengers report to muster stations.

 

This incident will be investigated internally, and bridge management practices and procedures adjusted accordingly.  It really is a minor incident.

MMA grad?  What year?  My husband graduated in 1998. Engine.  

Share this post


Link to post
Share on other sites
1 hour ago, Aunu said:

MMA grad?  What year?  My husband graduated in 1998. Engine.  

Nope, as my avatar says, KP '75.

Share this post


Link to post
Share on other sites
2 minutes ago, chengkp75 said:

Nope, as my avatar says, KP '75.



Sorry didn't have my glasses on, couldn't see what it says.  I saw people calling you chief and saw that youre in Maine. Guess thats what i get for assuming.  🙂 

Edited by Aunu
added

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Forum Jump
    • Categories
      • 2019 Cruisers' Choice Awards
      • NCL Sail-Away Giveaway Sweepstakes - Win a 7-Day Cruise on Norwegian Joy!
      • Forum Assistance
      • New Cruisers
      • Community Contests
      • Cruise Lines “A – O”
      • Cruise Lines “P – Z”
      • River Cruising
      • ROLL CALLS
      • Digital Photography & Cruise Technology
      • Member Cruise Reviews
      • Special Interest Cruising
      • Cruise Discussion Topics
      • UK Cruising
      • Australia & New Zealand Cruisers
      • North American Homeports
      • Ports of Call
      • Cruise Conversations
×
×
  • Create New...