Suction Or No Suction? (POLL)

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Yes

No

Dont Know

[matt105]

Ok this may seem strange but im interested to see the results.

I have recently seen on 'Mythbusters" that there is no suction on a ship when it is sinking.
They tried it on a 3/4 tonne boat and they found there was no suction. (So they calculated and said
Myth Busted)

BUT.

I was wondering if the results would change if they tested a ship like the size of the "Titanic" and
see if there was suction. (Even tho they cant test it the size of this ship.)

So what do you think? Would there be a suction or wouldn't there?

Cheers, Matt

[groennegaard]

Fortunately I don't have any personal expirience with sinkings, but time and time again, survivers have told of this suction, so and I tend to believe them.

A major vessel sinking, will always cause a down stream of water, kind of like racing cyclists braking the wind for one another.

Then there is the water density to consider. With air bubbles escaping from the vessel, the water will be less dense, making it easier to sink.

Regards
groennegaard

[Mad_Fred]

I tend to think that you can indeed be pulled under when a ship goes down.

But it depends on how fast a ship sinks I think, and also you could get caught in a flow of water rushing into the ship perhaps.

And as Groennegaard says, escaping air bubbles would make the water less dense indeed..

But I don't think it's a prolounged suction, so once the ship is under you should be able to break free..

But hey, that's just a guess. Fortunatly I have no experience with sinkings either. Not counting a punctured air matrass at the beach..  Didn't suck me under though..   


Fred

[mvsmith]

“Suction” is probably not the correct term. When the ship goes down, water follows it—if you are in that water, so do you.
Marty

[Minime]

Nope you wont go down

[mvsmith]

Do you fly instead?

[JHB]

Superman catch you and take you to Louis Lanes home so she can chill ya up

[Captain Spencer]

or maybe spiderman comes to rescue you?

Although I have no experience I think that when a major ship sinks you will be pulled underwater. This is because the water as Marty said would need to follow the ship to fill it up. The down movement of the ship will start to create a flow of water downwards, so obviously anything in that path of water (which would usually be above the ship) would also follow it.

Like I said, I have no experience on this, although my limited understanding of physics tells me thats what would happen. It's kind of like when a car goes past you, air follows it (after being pushing out of the way) and if you're in that path, it wants you to go with it Scream if you want to go faster!!

[marcstrat]

Greetings,
This is not a Moby Dick sim,however i have ships seen ships fly
This can be the new bug,a big vortex under your vessel.
 
Marc

[mvsmith]

Then there is the water density to consider. With air bubbles escaping from the vessel, the water will be less dense, making it easier to sink.

One constant but remote danger on a drilling ship is hitting a pocket of natural gas that forms a big bubble under the ship. A Japanese R/V that disappeared is thought to have suffered such a fate. She was working on a mid-ocean rise where oceanic plates are formed by magma rising through the crust.
Marty

[Cobrattack]

I can tell you for a fact that the US Navy teaches us that if you are on a Ship and it is going down you had better swim your butt off to have any chance of survival, and like all things in the Navy, this info comes from experience and because people have lost their lives because of it.  Of course we are talking about a small city (Carrier) sinking not just a little Row Boat!!  So in short if you are on a ship that is going down I really wouldn't trust Myth Busters on this one 

[Ship Sim]

I think it will suck you under. I dont trust the mythbusters on this one either because they used a small tug boat not a big ship.

[sadsid (†2016)]

In Febuary 1974 i sailed from fleetwood bound for iceland in the fishing trawler Wyre Victory
we struck mills reef (suel sigur)Scotland hebrides we were making passage to the sounds to
avoid bad weather force 9-10 beufort scale.
We struck the reef at 6-40 in the morning and the ship sank at 10-30 after coming clear of it
the 18 crew were picked up by the sister ship Wyre Conquerer we watched the vessel sink
Her keel had been ripped open at first she went down by the head then laid over on her side
slowly righted herself and started sinking bow first. we were steaming in a circle round the vessel
watching this very close .
when most of the vessel was under only stern showing all we could here was a loud whistling sound
 were the air was being forced from the ship.
we were close enough to see that even though completly sumerged the lights were still on as she went
down.
the captain circled the area for 20 min before taking the crew to oban to be put ashore
 the 20 mins    were o pick up anything the ship left there was nothing no lifebelts no deckboards
nothing so to me yes there is suction as the ship goes down

[pigdog]

Hi All interesting subject,

You would get "sucked under" to a certain extent, sucked is probably the wrong word but basically what happens is as groennegaard say's as the ship sinks the water rushing in expells the air inside the hull, this air will find it's way out of the smallest gap through windows, doors, cracks and it can even pop rivets, screws and bolts etc with great force, this air forms air bubbles within the water and obviously rises to the surface, as it breaks the surface the surface tension of the water is broken therefore offering no bouyancy, that is why a lot of ships break their backs when sinking because of a lack of bouyancy, this also explains Marty's post about the drilling ship hitting a pocket of gas again it offered no boyancy to the ship when it reached the surface.

There can also be a whirlpool effect but this depends on the angle and speed that the ship sinks, if it picks up speed as it takes on water and before dissapearing under the surface the water cannot replace the space that the ship occupied quick enough or (the water it once dissplaced when afloat) this in combination with the air forced out of the ship leaves a void so the water fights with the air to fill the space causing a whirpool but this won't take you to the bottom with your ship just deep enough until your natural boyancy equals or is greater than the depth of water you are in, that is if you haven't swallowed a ton of water and expelled the air from your lungs you could very well pop back up like a cork but the chances are panic and shock would have had an effect on you.

There are other forces at work including weather, gravity and the design or shape of the sinking vessel etc but the thing is every ship and situation is different there are no set rules as to what happens when a ship sinks just a set of basics that are known but one things for sure you wouldn't want to be on one when it goes down, luckily I never have and hope I never will (The best lifeboat you can have is your ship).

[JHB]

Talking about the title of this topic...

(now I know why this forum have so few Spambots )

[matt105]

Ok well i have the majority of the votes, And yes i would not believe that Mythbusters got the right calculations as they did only use a small tug.

Well Here is the words "Myth Confirmed"

Cheers, Matt

[Mad_Fred]

Talking about the title of this topic...

(now I know why this forum have so few Spambots )

It's not the words.. it's the mind that interprets them...   

 

Regards,
Fred