Barnacles on the Eclipse

[Redking]

I've been reading on the book of visage (hope that's not too heavily coded) that the Eclipse is loosing a day on its restart voyage due to barnacles on the hull. Can anyone please enlighten? For the Brits on here, reminded me of the then British Rail leaves on the line debacle back in the circa 90s.

[chengkp75]

1 hour ago, Redking said:

I've been reading on the book of visage (hope that's not too heavily coded) that the Eclipse is loosing a day on its restart voyage due to barnacles on the hull. Can anyone please enlighten? For the Brits on here, reminded me of the then British Rail leaves on the line debacle back in the circa 90s.

First off, you can refer to Facebook as Facebook, no code needed, you just can't link to it.

 

I don't follow Facebook, nor any particular line or ship, so do you mean that Eclipse will be slowed in reaching her final destination (I'm guessing it is down under) by barnacles?  That could be the case, or not.  If she has been sitting virtually stationary during the shutdown, she may have a good load of barnacles.  Modern anti-fouling paint on the ship's underwater area requires water moving past the hull to remove dead marine growth, and paint where the toxin has been depleted, in order to present new toxin on the surface.  This is one reason the ships would move around during the shutdown, as well as making water and discharging waste, to try to keep the hull clean.  Can a load of barnacles cause the ship to mover slower?  Maybe.  It depends on what speed the itinerary was set for, in relation to the maximum speed of the ship.  In many cases, they can just burn more fuel to provide more power to overcome the drag of the marine growth, and still get up to speed.  In some cases, the growth is too much, or the required speed to meet the itinerary is too high to overcome.  However, for a trip from Canada to Oz/NZ, it would be hard to predict whether the marine growth will affect the timing, unless there is a major coating of growth.  Too many factors like weather, currents, and whether the anti-fouling paint will start to slough off growth as the time that the ship is moving at speed will determine whether she is late.  If there was that much growth, I would have thought they would have had divers down before the voyage to "brush-cart" remove the growth as best they can, to minimize the drag.

[Beachin2]

2 hours ago, chengkp75 said:

First off, you can refer to Facebook as Facebook, no code needed, you just can't link to it.

 

I don't follow Facebook, nor any particular line or ship, so do you mean that Eclipse will be slowed in reaching her final destination (I'm guessing it is down under) by barnacles?  That could be the case, or not.  If she has been sitting virtually stationary during the shutdown, she may have a good load of barnacles.  Modern anti-fouling paint on the ship's underwater area requires water moving past the hull to remove dead marine growth, and paint where the toxin has been depleted, in order to present new toxin on the surface.  This is one reason the ships would move around during the shutdown, as well as making water and discharging waste, to try to keep the hull clean.  Can a load of barnacles cause the ship to mover slower?  Maybe.  It depends on what speed the itinerary was set for, in relation to the maximum speed of the ship.  In many cases, they can just burn more fuel to provide more power to overcome the drag of the marine growth, and still get up to speed.  In some cases, the growth is too much, or the required speed to meet the itinerary is too high to overcome.  However, for a trip from Canada to Oz/NZ, it would be hard to predict whether the marine growth will affect the timing, unless there is a major coating of growth.  Too many factors like weather, currents, and whether the anti-fouling paint will start to slough off growth as the time that the ship is moving at speed will determine whether she is late.  If there was that much growth, I would have thought they would have had divers down before the voyage to "brush-cart" remove the growth as best they can, to minimize the drag.

Greetings Chief,

 

The Eclipse spent the lay-up off the coast of San Diego, coming and going for provisions, etc as needed.  Is currently in Vancouver scheduled for her first Alaska run this weekend.

 

Maybe an Alaskan waters environmental restriction?

[mahdnc]

2 hours ago, chengkp75 said:

First off, you can refer to Facebook as Facebook, no code needed, you just can't link to it.

 

You cannot direct people to Facebook roll calls without the use of a link either. 

 

 

 

Edited April 24, 2022 by mahdnc

[chengkp75]

18 minutes ago, Beachin2 said:

Greetings Chief,

 

The Eclipse spent the lay-up off the coast of San Diego, coming and going for provisions, etc as needed.  Is currently in Vancouver scheduled for her first Alaska run this weekend.

 

Maybe an Alaskan waters environmental restriction?

Her AIS shows the next port as Hilo?  This morning she was in the Straits of Juan de Fuca on her way out.  Some ports don't allow cleaning the hull in port, and it may be a limitation in Alaska, but frequently there are places the ship can anchor outside of the port proper and get an in-water cleaning.

[Wondermouse]

People on the ship at present are losing Hilo apparently due to the slow speed the ship will have to travel. I agree about cleaning it prior to it going out for its restart voyage. 

[chengkp75]

6 minutes ago, Wondermouse said:

People on the ship at present are losing Hilo apparently due to the slow speed the ship will have to travel. I agree about cleaning it prior to it going out for its restart voyage. 

Ah, so this was to be a  "fire and ice" Hawaii and Alaska cruise?

[Wondermouse]

No, just Hawaii, followed by another Hawaii then back to Vancouver. We are on the return starting May 4.  The current passengers are preparing us that we may lose a port due to this as well. 

[rotoal]

Eclipse went into a drydock and her hull was painted at some point during the shutdown.

 

I wonder how this barnacle problem will impact the Alaska season.

[Redking]

@chengkp75 thank you for your detailed response, very interesting. 

[Northern Aurora]

I am posting from the Eclipse.  We boarded yesterday in Vancouver on the first passenger cruise for the Eclipse since the global suspension of sailing.

 

We received letters indicating that due to “recent marine growth … known as barnacle growth” our speed to Hawaii will be slower than typical.  We have not lost Hilo as a port but instead of overnighting in Hilo we will be there from 7 AM to 10 PM on April 30th.  

 

On May 4th the ship will return to Vancouver (we are B2B) and then start their Alaska season which are RTs out of Vancouver.  I asked whether the Alaska season will be impacted, and they don’t anticipate any issues since the distances between ports are so short.

[2Long2NxtCrz]

1 hour ago, Northern Aurora said:

On May 4th the ship will return to Vancouver (we are B2B) and then start their Alaska season which are RTs out of Vancouver.  I asked whether the Alaska season will be impacted, and they don’t anticipate any issues since the distances between ports are so short.

The May 4th itinerary didn't have an overnight in Hilo, does it appear that we won't lose that port?

I'm a bit concerned because we booked a car through Turo and I need to have time to cancel if we do lose Hilo.

 

[Northern Aurora]

29 minutes ago, 2Long2NxtCrz said:

The May 4th itinerary didn't have an overnight in Hilo, does it appear that we won't lose that port?

I'm a bit concerned because we booked a car through Turo and I need to have time to cancel if we do lose Hilo.

 

 

 

The April 23rd itinerary originally overnighted in Hilo arriving on April29th and departing on April30th.  We will now spend April30th in Hilo.   We are still overnighting in Lahaina.

 

If I can obtain any definitive information from what I consider to be a reliable source regarding potential changes in the May 4th itinerary I will post on the May 4th roll all.

[2Long2NxtCrz]

On 4/24/2022 at 5:28 PM, Northern Aurora said:

 

 

The April 23rd itinerary originally overnighted in Hilo arriving on April29th and departing on April30th.  We will now spend April30th in Hilo.   We are still overnighting in Lahaina.

 

If I can obtain any definitive information from what I consider to be a reliable source regarding potential changes in the May 4th itinerary I will post on the May 4th roll all.

Thanks so much!

[JRG]

On 4/24/2022 at 2:49 AM, chengkp75 said:

Can a load of barnacles cause the ship to mover slower?  Maybe. 

 

It is  not a Maybe it is a Definitely,  just a matter of how much.    And it is much worse if  the barnacles are on the propeller or pod.

 

Physics and Marine Biology.

[chengkp75]

22 minutes ago, JRG said:

 

It is  not a Maybe it is a Definitely,  just a matter of how much.    And it is much worse if  the barnacles are on the propeller or pod.

 

Physics and Marine Biology.

No, as I said, it may create more drag, and therefore require more power to achieve the same speed (simple physics), but if the ship has enough reserve power to reach the desired speed, the barnacle drag only results in increased fuel consumption.  Does a pickup truck bed with a closed tailgate have more wind resistance (drag) than when the tailgate is open?  Sure.  Does that mean the truck goes slower?  No, just push on the pedal harder.  Big difference between resistance and speed, and that difference is power.

[hrhdhd]

1 hour ago, chengkp75 said:

No, as I said, it may create more drag, and therefore require more power to achieve the same speed (simple physics), but if the ship has enough reserve power to reach the desired speed, the barnacle drag only results in increased fuel consumption.  Does a pickup truck bed with a closed tailgate have more wind resistance (drag) than when the tailgate is open?  Sure.  Does that mean the truck goes slower?  No, just push on the pedal harder.  Big difference between resistance and speed, and that difference is power.

From Popular Mechanics (emphasis added): Driving with the tailgate down increases the drag and thus is less fuel efficient than driving with the tailgate up. The closed tailgate creates a vortex in the bed of the truck that allows for smoother flow of air than when the tailgate is down and the vortex is dispersed.

[chengkp75]

16 minutes ago, hrhdhd said:

From Popular Mechanics (emphasis added): Driving with the tailgate down increases the drag and thus is less fuel efficient than driving with the tailgate up. The closed tailgate creates a vortex in the bed of the truck that allows for smoother flow of air than when the tailgate is down and the vortex is dispersed.

Okay, so turn my example around, I stand corrected, but my premise is correct.  The position of the tailgate does not make the truck faster or slower.

[mahdnc]

22 minutes ago, hrhdhd said:

From Popular Mechanics (emphasis added): Driving with the tailgate down increases the drag and thus is less fuel efficient than driving with the tailgate up. The closed tailgate creates a vortex in the bed of the truck that allows for smoother flow of air than when the tailgate is down and the vortex is dispersed.

 

I actually studied this fluid dynamics problem when I was at Caltech!  Very useful  to get a job.  Not so much to get a girl.

Edited April 26, 2022 by mahdnc

[Northern Aurora]

@chengkp75’s comments and insights are always so interesting.  I am posting from the Eclipse and was told (by a concierge) that we have two meters of barnacle buildup on each side of the ship.

[chengkp75]

8 minutes ago, Northern Aurora said:

@chengkp75’s comments and insights are always so interesting.  I am posting from the Eclipse and was told (by a concierge) that we have two meters of barnacle buildup on each side of the ship.

Typically, the largest amount of marine growth on a static ship will be at the waterline, but that is more "grass" than barnacle, the barnacles tend to be further down, along the bottom.  The grass should slough off as the ship steams at speed, the barnacles, not so much.  I spent a few years on a small tanker that was stationary for 300+ days a year for about 3 years, and even after 3 underwater hull cleanings, when we got to drydock, they removed about 65 cubic yards of hard barnacle and oyster growth from the hull (about 2" deep along the entire flat bottom), and that amount of growth only slowed us by about 15% on top speed (but required about 50% more fuel to do it).  Eclipse should get better with time underway (the trips back and forth to Hawaii should be a great help), but even when you remove the dead barnacles, the little "attachment" disc they leave behind becomes drag and also a future attachment point for another barnacle.

[canderson]

@chengkp75

Have you any experience with hull mounted ultrasonic transducers for smaller ships?  The best of them reduce barnacle adhesion to near zero.

 

 

Edited April 26, 2022 by canderson
Typoz

[chengkp75]

1 hour ago, canderson said:

@chengkp75

Have you any experience with hull mounted ultrasonic transducers for smaller ships?  The best of them reduce barnacle adhesion to near zero.

 

 

No, never seen them.  Large ships use a copper based anti-fouling paint, where the copper compound kills the growth, or newer, faster ships like cruise ships use a teflon bottom paint, where the hard, smooth surface gives no point of adhesion for the growth.  Some large ships may use ultrasonics for the seawater piping, more traditional are impressed current systems that cause a copper anode to corrode at a controlled rate to inject copper into the sea water entering the pipes.

[talljules1]

Well, I am a bit disappointed by this thread.

 

I thought it was going to be about a menu change from escargot in the main dining room.

[lobsternight]

My dear old Dad had a sure-fire solution for barnacles.  Once a year he would haul out his boat and hand me a scraper.