Silhouette vibration

On the Eclipse a few weeks ago, we were on a B2B - first cabin on the hump on starboard side, I felt quite a lot of vibration, but second leg we changed to the port side and didn't feel any vibration!

We are booking Silhouette next year and wondering whether anyone noticed any more vibration on one side of the hump than the other?

What was your cabin number? We are sailing on Eclipse next year.

Thanks.

Propulsion problem perhaps? There was a show on Smithsonian a few months back about the building of one of the new NCL mega-ships. They had a problem syncing the main screws and vibration was one of the things they talked about.

Mid-ship vibration is not likely from the Azipods. Folks need to understand that the heaviest machinery (which includes the large engines) are arrayed over the ship's center of gravity. There are many pieces of major machinery that can cause some vibration in a cabin so it would be crazy to make a guess. I should add that this is one reason why DW and I are contrarians and have long enjoyed cabins located up closer to the bow. There is very little mechanical vibration towards the bow (expect when they use the bow thrusters during the docking process) and there is also much less foot traffic at that part of the ship. And yes, the bow can suffer more movement in rough seas....but for us...that is just like being a baby rocked to sleep.

Hank

Hmm... could be the stabilizers I suppose - but why only on one side?

Not very disturbing, but as I have inner ear problems, it was irritating at times. I stress, very slight and my partner didn't notice.

As Hank says, azipod shimmy is generally not felt except very far aft. Even a prop synch problem would not cause vibration on one side or the other. Also as Hank says, the machinery is generally the length of the ship, but from looking at the deck plans, the hump is slightly forward of the funnels, about where the forward engine room would be (or a little forward of it). Now, depending on the speed the ship needed to make, and the maintenance schedule at the time, they may have been running the two starboard engines, and not the port engines, and this could cause the imbalance between sides. Simply a guess on my part, and it could also be weather related (which side the wind was from, what the course was), and what changed in this environment between the two cruises, but I would say there is no way to pre-determine this.

We had serious vibration on the port side aft of the elevators on Eclipse this past January. I think we were on the 11th deck (??) so I did not expect engine noise that high up. It was even a problem in port when I would expect it would not be if it were due to engine propulsion. It ranged from very bad at times (preventing me from sleeping) to moderate to very mild with no discernable rhyme or reason that we could tell. Guest Relations didn't care a bit when I asked them about it. Got a blank stare like I was a zombie with three heads talking to them, and a nothing we can do about it response. I suspect they were getting a lot of complaints. Not sure if this problem always exists or if something was wrong. If the latter, they were not willing to admit it.

Thank you Pheonix - good to know it wasn't only my imagination!! Wonder what's wrong with her?

However, seems no-one has noticed anything wrong with the Silhouette, so I should be OK.

Thanks for your replies y'all!!

Thank you Pheonix - good to know it wasn't only my imagination!! Wonder what's wrong with her?

 

However, seems no-one has noticed anything wrong with the Silhouette, so I should be OK.

 

Thanks for your replies y'all!!

Just off the Silhouette cabin 9227. Lots of vibration but not all the time noticed it in the cabin and also buffet. It seemed more noticeable the higher up we were on the ship. Certainly was not enough to really be a problem for us.

Off the Eclipse end of September in CS 1237 (deck 10 hump , port side), was a little vibration first night, and then again one again mid way through cruise, but nothing that kept us awake or spoiled our stateroom comfort.

On the Equinox, in the Oceanview Cafe, sitting along the wall on the port side about a third of the way into the room and there was so much vibration that I felt if I continued to sit there I'll be sick. Further forward or aft in the Buffet I did not feel it.

Another cause of random vibration can be caused by combinations of weather (wind and seas in relation to the ship) and the rpm the propellers are spinning at. Since the ship is virtually a large "sounding box" (think of a guitar or violin), if the propellers are turning at the harmonic frequency of a particular portion of the ship (a smaller sounding box within the larger), that part of the ship (cabin or public space) can start to vibrate in harmonics. Changing the speed of the propellers by as little as 1 rpm, or changing the heading can stop the harmonics in that space, but may induce it in another.

Another cause of random vibration can be caused by combinations of weather (wind and seas in relation to the ship) and the rpm the propellers are spinning at. Since the ship is virtually a large "sounding box" (think of a guitar or violin), if the propellers are turning at the harmonic frequency of a particular portion of the ship (a smaller sounding box within the larger), that part of the ship (cabin or public space) can start to vibrate in harmonics. Changing the speed of the propellers by as little as 1 rpm, or changing the heading can stop the harmonics in that space, but may induce it in another.

Guess we could go into long explanations of Cavitation......which we know has driven marine architects and engineers to drink :). But the simple bottom line is that vibration does happen on ships, is generally more common aft of amidships, and is unlikely to be totally eliminated in the newest builds. We consider it just one of those things that goes with being on a ship.

Hank

Just off the Silhouette cabin 9227. Lots of vibration but not all the time noticed it in the cabin and also buffet. It seemed more noticeable the higher up we were on the ship. Certainly was not enough to really be a problem for us.

Yikes!! However, on Eclipse B2B much more noticeable in cabin on starboard side. Oh well, here's hoping our starboard hump will avoid excess vibration.