2kiwis Posted February 26, 2013 #1 Share Posted February 26, 2013 Just finished 28 days on Marina. The ship is beautifully appointed but after numerous cruises in all sorts of weathers on the R ships, we were surprised by the way Marina seemed to roll a lot - even in calmer waters Several others with us also thought that Marina didn't seem to be as stable as the smaller ships. Maybe this is just because it is bigger or maybe the way it has been designed? Link to comment Share on other sites More sharing options...
ricki Posted February 26, 2013 #2 Share Posted February 26, 2013 We were on Marina last April and were unable to anchor in Amalfi/Positano because of rough seas. We thought Marina handled the rough seas well with little pitch or yawl. Ricki Link to comment Share on other sites More sharing options...
Rare DOJO466 Posted February 26, 2013 #3 Share Posted February 26, 2013 Just finished 28 days on Marina. The ship is beautifully appointed but after numerous cruises in all sorts of weathers on the R ships, we were surprised by the way Marina seemed to roll a lot - even in calmer waters Several others with us also thought that Marina didn't seem to be as stable as the smaller ships. Maybe this is just because it is bigger or maybe the way it has been designed? I have been on Marina 3 times and think the same thing. Link to comment Share on other sites More sharing options...
Mura Posted February 26, 2013 #4 Share Posted February 26, 2013 I confess I'm surprised to read these comments. We've only been on Marina once whereas we've been on Oceania's three other "R" ships several times and we didn't notice a problem with Marina's stability. And I tend to be prone to mal de mer. Maybe we were just lucky. Mura Link to comment Share on other sites More sharing options...
Hawaiidan Posted February 26, 2013 #5 Share Posted February 26, 2013 Is due not so much the design ( with the exception of flat bottom barges and LST's) but the state of the sea, wind and prevailng course across , into or with currents. Take 3 similiar ships, put all three in the same ocean at the same spot doing the same thing and you wont be able to tell who is who. THe ocean is in charge. Ships all have ballast tanks that can adjusted m a even keel and centr of gravity... Stabilizers dont work below 10 kts. So if your doing 12kts in 3kt current thats is only 9 kts over the stabilizer and they wont work. The whole matter of stability is in the eye of the beholder...you and rules by the sea Link to comment Share on other sites More sharing options...
YoHoHo Posted February 26, 2013 #6 Share Posted February 26, 2013 I Stabilizers dont work below 10 kts. So if your doing 12kts in 3kt current thats is only 9 kts over the stabilizer and they wont work. The whole matter of stability is in the eye of the beholder...you and rules by the sea That is interesting stat on the stabilizers. While at sea the ship is cruising well above that of course but coming into port, especially were there can be a lot of wind like Positano I am sure thy would like to have them working but this explains why they can't . I assumed like aircraft surfaces there were minimum speeds to effectiveness but did not realize this low, especially as you say with a strong current. Link to comment Share on other sites More sharing options...
findacruise Posted February 26, 2013 #7 Share Posted February 26, 2013 We were just on the HAL Noordam in the Caribbean and had very high winds and some rough seas. We were not able to port at Grand Turk. The captain, who has been with that ship since 6 months before her maiden voyage, said it was the first time ever he has not been able to dock there. We had terrible cross winds. We watched him try to get the ship in position and it was a losing battle. He said it wasn't safe to continue trying. There were 3 nights out of 10 that we had some rock and roll and some days with very high seas. I don't know where the OP was, but these were some of the worst winds we have encounter while we have been in the Caribbean in February. The last few times have been with Oceania. Link to comment Share on other sites More sharing options...
Rare LHT28 Posted February 26, 2013 #8 Share Posted February 26, 2013 I don't know where the OP was, but these were some of the worst winds we have encounter while we have been in the Caribbean in February. The last few times have been with Oceania. It can happen even in February We were hit with a rogue wave on the Regatta a few years ago went up over the walking track...some man was in the smoking area & DH had talked to him the next day ..he was shocked to say the least I thought we hit a container & was waiting for the abandon ship call :eek: We had 36 hrs of rocking & rolling Lyn Link to comment Share on other sites More sharing options...
joysav Posted February 27, 2013 #9 Share Posted February 27, 2013 Ships all have ballast tanks that can adjusted m a even keel and centre of gravity... Stabilizers dont work below 10 kts. So if your doing 12kts in 3kt {following ??} current that's is only 9 kts over the stabilizer and they wont work. The whole matter of stability is in the eye of the beholder...you and rules by the sea We have had a run on Cable down here in Oz on Ships in general and Cruiselines. I can clearly remember 2 instances of rough seas and the pools being emptied and the ballast tanks being filled up to sit the ship lower in the water. Big deal for the Captains as it increases the Fuel Consumption As Hawaiidan said "The whole matter of stability is in the eye of the beholder." Maybe the Captain did not fill the ballast tanks on the Mariner to save fuel. :confused: Link to comment Share on other sites More sharing options...
Hawaiidan Posted February 27, 2013 #10 Share Posted February 27, 2013 Is not used to make the ship sit lower since water has the same density as the sea its push Water erighs the same Water, fuel etc is all used as ballast and the ships engineering officer are constantly shifting fluids around in order to maintain the design center of gravity that the builders sought to create. ( airplanes do this too with their fuel) Adding cargo higher density than the sea will raise the waterline. Actualy, increasing the waterline increases not decreases the ships speed ( refer to hull speed calculations which are the square of the waterline x a factor I forgot)in a displacement hull.:rolleyes: A note on Shipping in tand around OZ coming from the east to west the prevailing currents and the continent of OZ create huge swells the closer you get to land... Same thing sailing from Fiji to New Zealand or New South Whales to Tasmania..( nasty water the Bass Str) Link to comment Share on other sites More sharing options...
rundent Posted February 27, 2013 #11 Share Posted February 27, 2013 When you pump in sea water to create more ballast aren't you displacing air? This would make the ship denser and therefore sit lower in the ocean. Of course, if you do too much of this it's called sinking. Link to comment Share on other sites More sharing options...
Miata6 Posted February 28, 2013 #12 Share Posted February 28, 2013 It can happen even in February We were hit with a rogue wave on the Regatta a few years ago went up over the walking track...some man was in the smoking area & DH had talked to him the next day ..he was shocked to say the least I thought we hit a container & was waiting for the abandon ship call :eek: We had 36 hrs of rocking & rolling Lyn Lyn, when and where was the rogue wave? We were on a T/A on Regatta in 2007 where waves were coming over the track onto the pool area. Were we on the same voyage? (We'll never forget it!) Jon Link to comment Share on other sites More sharing options...
Rare LHT28 Posted February 28, 2013 #13 Share Posted February 28, 2013 Lyn, when and where was the rogue wave? We were on a T/A on Regatta in 2007 where waves were coming over the track onto the pool area. Were we on the same voyage? (We'll never forget it!) Jon We were going from Grand Cayman to Columbia not sure if it was 2007 or 2008 but I can tell you it was a bumpy ride :D When it hit the ship the whole ship shook ..we were in our cabin on deck 4 & I seriously was getting the life jacket ready:eek: Lyn Link to comment Share on other sites More sharing options...
Hawaiidan Posted February 28, 2013 #14 Share Posted February 28, 2013 When you pump in sea water to create more ballast aren't you displacing air? This would make the ship denser and therefore sit lower in the ocean.Of course, if you do too much of this it's called sinking. Thats true only to that extent with submarines which have way more ballast. They get to netural and use power and diving planes to submerge. Other wise the submarine would continue to sink to the bottom. Divers do this too in SCUBA. The real function of ballast is to maintain center of gravity, counteract a list caused by structural damage , cargo shift or windage ( the effect of wind on the superstructure will cause a slight list. It is simple physics to shift density to one side ot the other of the CG as desired like a teter totter. Weighting one side of the lever more than the other. Going deeper in the water will have no effect on the stability only hull speed. The reason they pump the pools is that this is a large weight on a high upper deck ( picture a weight attached to a lever arm) and the pools have no baffels to control fluid motion. As the un baffeled pools begin to roll the water begins to slosh from side to side developing kenitic energy or forces. With each slosh the energy or force being developed builds to where it is and can be a destructive element. ( force is = to mass x velocity x time) Refer to the US Navy watch officers guide and Damage control manual. Link to comment Share on other sites More sharing options...
YoHoHo Posted February 28, 2013 #15 Share Posted February 28, 2013 When you pump in sea water to create more ballast aren't you displacing air? This would make the ship denser and therefore sit lower in the ocean.Of course, if you do too much of this it's called sinking. LOL Another example of too much of a good thing ... Link to comment Share on other sites More sharing options...
GITC Posted February 28, 2013 #16 Share Posted February 28, 2013 Anybody else open this thread expecting to find a review of the musical entertainment? :p :D Link to comment Share on other sites More sharing options...
2kiwis Posted February 28, 2013 Author #17 Share Posted February 28, 2013 Anybody else open this thread expecting to find a review of the musical entertainment? :p :D For those who did, the band in horizons on Marina was by the far the best band we have even heard at sea = they were amazing. The reason why so many of us stayed up late dancing the night away. Link to comment Share on other sites More sharing options...
Rare LHT28 Posted February 28, 2013 #18 Share Posted February 28, 2013 For those who did, the band in horizons on Marina was by the far the best band we have even heard at sea = they were amazing.The reason why so many of us stayed up late dancing the night away. What is the name of the band? We have had some good house bands on Oceania Lyn Link to comment Share on other sites More sharing options...
Tropiclady Posted February 28, 2013 #19 Share Posted February 28, 2013 What is the name of the band? We have had some good house bands on Oceania Lyn They were the Siglo band. Absolutely awesome! Hi 2kiwi's! The band is from the Phillipines and for many years preformed on the Paul Gaugin. Cheers, Tropiclady Link to comment Share on other sites More sharing options...
Rare LHT28 Posted February 28, 2013 #20 Share Posted February 28, 2013 They were the Siglo band. Absolutely awesome! Hi 2kiwi's! The band is from the Phillipines and for many years preformed on the Paul Gaugin. Cheers, Tropiclady Thanks Most of the ones we have had were from eastern European countries along with the quartets Lyn Link to comment Share on other sites More sharing options...
2kiwis Posted March 1, 2013 Author #21 Share Posted March 1, 2013 They were the Siglo band. Absolutely awesome! Hi 2kiwi's! The band is from the Phillipines and for many years preformed on the Paul Gaugin. Cheers, Tropiclady That's them . . . they were fantastic!!! Link to comment Share on other sites More sharing options...
joysav Posted March 1, 2013 #22 Share Posted March 1, 2013 Is not used to make the ship sit lower since water has the same density as the sea its push Water weighs the same Water, fuel etc is all used as ballast and the ships engineering officer are constantly shifting fluids around in order to maintain the design center of gravity that the builders sought to create. Are you sure ?? Why do oil tankers sink to their Plimsol Line ?? when they load with Oil ?? Oil is generally lighter than Water ?? Crude oil is classified as light, medium, or heavy, according to its measured API gravity. - Light Crude has an API gravity higher than 31.1 °API. - Medium Crude has an API gravity between 22.3 °API and 31.1 °API. - Heavy Crude has an API gravity below 22.3 °API. API Gravity is a measure of how heavy or how light a petroleum liquid is compared to water. If its API gravity is greater than 10, it is lighter and floats on water; if less than 10, it is heavier and sinks. Most values fall between 10 and 70 API gravity degrees. And if you added ballast (Sea Water) into huge bags/bladders above the water line the ship would lower in the Water ?? So if we empty & moved these bladders down below the water line and refilled these with seawater the boat would not lower to the point where it was when they were above the waterline. ?? . Link to comment Share on other sites More sharing options...
joysav Posted March 1, 2013 #23 Share Posted March 1, 2013 Actualy, increasing the waterline increases not decreases the ships speed ( refer to hull speed calculations which are the square of the waterline x a factor I forgot)in a displacement hull.:rolleyes: So why don't Cruise Liners sit lower in the water to conserve Fuel :confused: and move the centre of gravity (G B and M )a bit higher to help the poor souls in Penthouse Suites Link to comment Share on other sites More sharing options...
rundent Posted March 1, 2013 #24 Share Posted March 1, 2013 Ah, Archimedes where are you when we need you? Link to comment Share on other sites More sharing options...
joysav Posted March 2, 2013 #25 Share Posted March 2, 2013 Ah, Archimedes where are you when we need you? "Any object, wholly or partially immersed in a fluid, is buoyed up by a force equal to the weight of the fluid displaced by the object. — Archimedes of Syracuse WIKI This is the simplistic law we all know BUT "with the clarifications that for a sunken object the volume of displaced fluid is the volume of the object. Thus, in short, buoyancy = weight of displaced fluid. Archimedes' principle is true of liquids and gases, both of which are fluids." WIKI etc etc Any how he invented Screwing and I think defined the Basic Beat / Tming of Music that makes it pleasurable to most people so he is a legend in my books . ;) Link to comment Share on other sites More sharing options...
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