How Many Knots of Wind Does it Take to Make a Ship Rocky?

[gemz]

Been on a few cruises when the ship starts to rock even on the Oasis but I never paid attention to what the wind speeds were when the ship rocks for these large ships. Is it winds speeds greater than 20 knots? Our last cruise on Ruby Princess was rocking a fair bit for one day last March but not excessive but noticeably.

[swedish weave]

Been on a few cruises when the ship starts to rock even on the Oasis but I never paid attention to what the wind speeds were when the ship rocks for these large ships. Is it winds speeds greater than 20 knots? Our last cruise on Ruby Princess was rocking a fair bit for one day last March but not excessive but noticeably.

 

One cause of rocking can be the swells coming toward the side of the ship. Doesn't necessarily have to be high winds although they can also have a major impact on the rocking. The stabilizers are not very effective if the ship is moving slowly. Another contributing factor.

 

One cruise I was on, someone asked the captain why the ship was rocking, and he replied "Too many honeymooners onboard".

[Aquahound]

That's an impossible question to answer. The winds can blow 30 knots with no effect on the ride. There are too many other factors to consider.....wind direction, fetch, water depth, draft, ship's course, ship's speed, etc, etc.

[ssb]

As aquahound said:

too many variables

[ehfl]

Rocking is caused by the waves, not the wind. The waves are caused by the wind, but there are a lot of variables, including how long the wind has been at some speed, as well as the fetch, the distance the wind has impacted the surface. You can have calm winds and high waves, if the waves had been generated over previous days, or you can have high winds an low waves, if there has not been enough time or distance for the waves to build.

 

The steepness of the waves also makes a big difference.

[ChipLondon]

Real Wind or Relative Wind ? :)

 

 

Been on a few cruises when the ship starts to rock even on the Oasis but I never paid attention to what the wind speeds were when the ship rocks for these large ships. Is it winds speeds greater than 20 knots? Our last cruise on Ruby Princess was rocking a fair bit for one day last March but not excessive but noticeably.

[Trainman-2]

A 20-30 kt wind is nothing when blowing straight onto the bow. Blowing straight onto the side of the ship is something else.

 

This is why you always hear of ships turning into the wind in a major storm.

 

As stated above, there are too many variables.

[cj_one2000]

One cruise I was on, someone asked the captain why the ship was rocking, and he replied "Too many honeymooners onboard".

 

Good theory :D Wouldn't be surprised! ;)

[tahqa]

That's an impossible question to answer. The winds can blow 30 knots with no effect on the ride. There are too many other factors to consider.....wind direction, fetch, water depth, draft, ship's course, ship's speed, etc, etc.

 

Rocking is caused by the waves, not the wind. The waves are caused by the wind, but there are a lot of variables, including how long the wind has been at some speed, as well as the fetch, the distance the wind has impacted the surface. You can have calm winds and high waves, if the waves had been generated over previous days, or you can have high winds an low waves, if there has not been enough time or distance for the waves to build.

 

The steepness of the waves also makes a big difference.

 

Heh, they said "fetch". I don't know what it is but it sounds cool! :D

[ehfl]

Heh, they said "fetch". I don't know what it is but it sounds cool! :D

 

http://en.wikipedia.org/wiki/Fetch_(geography)

[Big_G]

There isn't a ship afloat that could survive the combined wind on these Cruise Critic boards. ; - )

 

 

Sent from my iPad using Tapatalk

[swedish weave]

Heh, they said "fetch". I don't know what it is but it sounds cool! :D

 

It is what you teach your dog to do when you throw a stick !!!:D:o

[Jenn31708]

http://en.wikipedia.org/wiki/Fetch_(geography)

 

This page says:

 

Did you mean: Fetch (geography)

 

Wikipedia does not have an article with this exact name. Please search for Fetch (geography in Wikipedia to check for alternative titles or spellings.

Search for "Fetch (geography" in existing articles.

 

 

 

:confused:

[FLACRUISER99]

This page says:

 

Did you mean: Fetch (geography)

 

Wikipedia does not have an article with this exact name. Please search for Fetch (geography in Wikipedia to check for alternative titles or spellings.

Search for "Fetch (geography" in existing articles.

 

 

 

:confused:

Try this http://en.wikipedia.org/wiki/Fetch_(geography) Ehfl did not test the link, mine should work.

[Aquahound]

Heh, they said "fetch". I don't know what it is but it sounds cool! :D

 

Simply put, it's the distance over open water the wind has to travel, usually resulting in higher waves.

 

But it is a funny name. :D

[Arizona Cruz Chic]

As Aquahound said, its impossible to answer.

We have had what looked like calm seas, but the swells were what made more movement on the ship.

 

***

[gjkubel]

Rocking is caused by the waves, not the wind. The waves are caused by the wind, but there are a lot of variables, including how long the wind has been at some speed, as well as the fetch, the distance the wind has impacted the surface. You can have calm winds and high waves, if the waves had been generated over previous days, or you can have high winds an low waves, if there has not been enough time or distance for the waves to build.

 

The steepness of the waves also makes a big difference.

 

This is not entirely accurate as the wind hitting the ship can be a major factor in listing and rocking. Thus, though wind does cause waves, wind itself also greatly impacts the motion felt on the ship.

[gemz]

Thank you everyone. Great learning experience for me.