Airlines are required to give safety instructions at the beginning of each flight. There needs to be reviews of safety evacuation procedures for every passenger. People should be able to identify the stewards that would show them where the life rafts and emergency equipment are and how to use them. There should be no panic so much as informed movement to safety.
Outside of such precautions, people left to their own resolves are best to know there is an emergency. Drifting away is highly unlikely when the response is as intense as this. It was an incredible response by the South Koreans. In such dangers, it is best to drift away than sink with the ship and/or be pulled into the vacuum following the ship to the bottom of the sea. Most travelers don't understand the dangers of a sinking ship and how the physics dictates to move away from it rather than seek shelter as long as possible with it.
19 April 2014
Last updated at 06:12 ET
The captain of a South Korean ferry (click here) that sank this week said he delayed giving evacuation orders because he feared passengers would "drift away".
Lee Joon-seok, 69, was arrested with two crew members on Friday.
Divers saw three bodies in the ship on Saturday but were not able to retrieve them. The number of missing stands at 270 with 32 now confirmed dead, after three bodies were found in the water.
The official leading the rescue said it "may last one or two months."
Some 174 passengers were rescued, but poor visibility and strong currents are making the search - now in its fourth day - difficult.
The captain faces charges including negligence of duty and violation of maritime law after being criticised for not giving orders to evacuate soon enough.
Meanwhile relatives of the victims have begun providing DNA samples to help identify bodies recovered from the wreckage.
Investigations are focusing on a sharp turn the vessel took before it started listing and whether an evacuation order could have saved lives....
The "Free Surface Effect." That is what is suspected as the cause of this tragedy.
...Centre of gravity (click here) is affected by the position of all the masses in a body, while centre of bouyancy is affected by the cross-sectional shape of the fluid displaced. The centre of buoyancy is the centroid of the cross sectional shape of the displaced fluid, as seen from picture 2 and 3....
The problem with transporting cargo often enters into the stability of the cargo within the transport vehicle, no matter what that vehicle is. The center of gravity is important with ships and so is their displacement in the water. They are related.
Ferries fall into the category of "Roll On Roll Off" vessels.
The RoRo Shipping Specialist (click here)
RoRo is short for "roll on, roll off". This simply refers to the method by which vehicles and machinery are loaded onto large ocean shipping vessels for transport overseas. World Class Shipping is a leading provider of roro logistics services to individuals and corporations who wish to transport single or multiple vehicles....
Ferries, due to their width have a ratio to depth that is less than ocean going ships because the travel is expected to be short in duration and along a proven route that is mostly safe from ocean surface fluctuations.
It is true ferries have challenges to their stability, especially when passing by inlets where ocean waters mix with bay or coastal waters. A ferry can become unstable if hit with strong currents, but, most captains know their boats and the water they navigate and anticipate these currents.
I experienced and witnessed on ferries some very adept captains and crews as they travel across waters that become turbulent during storms or meet with incoming ocean turbulence. They primarily turn 'at angle' to the water rather than take it head on. That is not what happened here according to what is being reported.
From what I can discern, the government is stating a quick turn in the water 'created' a shift of weight on the ship that caused it to tumble. I suppose that is possible. Cars aren't anchored in place on ferries. And this ship was only recently in route so the amount of fuel would be significant while some would have been used for propulsion. I suppose there was enough room in the fuel tanks to cause problems with stability and it is very true ferries are precarious in water to begin with.
In this photo (click here) released by South Korea Coast Guard via Yonhap News Agency,
South Korean rescue team boats and fishing boats try to rescue
passengers of a ferry sinking off South Korea's southern coast, in the
water off the southern coast near Jindo, south of Seoul, on Wednesday.
Without any insult to the hull or evidence of collision, instability would come into question. This type of ferry is not at all unusual in the world. It is seen in most countries where water transport occurs. Ferries also operate in shallower waters because of their water displacement.
So, we are looking at human error. I am not an expert on these waters. I do find it odd that unless the crew were completely novice to this route a sudden change in direction knowing the capacity of the ship, seems odd to me. But. That is me and not the officials overseeing the investigation.
Odd because it would be irrational to turn quickly without sincere reason of danger to do so. Briefly leaving prescribed routes or wandering ever so much out of a shipping lane isn't a dire emergency if here is no peril nearby. I think this sudden turn in open water is very strange.
Outside of such precautions, people left to their own resolves are best to know there is an emergency. Drifting away is highly unlikely when the response is as intense as this. It was an incredible response by the South Koreans. In such dangers, it is best to drift away than sink with the ship and/or be pulled into the vacuum following the ship to the bottom of the sea. Most travelers don't understand the dangers of a sinking ship and how the physics dictates to move away from it rather than seek shelter as long as possible with it.
19 April 2014
Last updated at 06:12 ET
The captain of a South Korean ferry (click here) that sank this week said he delayed giving evacuation orders because he feared passengers would "drift away".
Lee Joon-seok, 69, was arrested with two crew members on Friday.
Divers saw three bodies in the ship on Saturday but were not able to retrieve them. The number of missing stands at 270 with 32 now confirmed dead, after three bodies were found in the water.
The official leading the rescue said it "may last one or two months."
Some 174 passengers were rescued, but poor visibility and strong currents are making the search - now in its fourth day - difficult.
The captain faces charges including negligence of duty and violation of maritime law after being criticised for not giving orders to evacuate soon enough.
Meanwhile relatives of the victims have begun providing DNA samples to help identify bodies recovered from the wreckage.
Investigations are focusing on a sharp turn the vessel took before it started listing and whether an evacuation order could have saved lives....
...Centre of gravity (click here) is affected by the position of all the masses in a body, while centre of bouyancy is affected by the cross-sectional shape of the fluid displaced. The centre of buoyancy is the centroid of the cross sectional shape of the displaced fluid, as seen from picture 2 and 3....
The problem with transporting cargo often enters into the stability of the cargo within the transport vehicle, no matter what that vehicle is. The center of gravity is important with ships and so is their displacement in the water. They are related.
Ferries fall into the category of "Roll On Roll Off" vessels.
The RoRo Shipping Specialist (click here)
RoRo is short for "roll on, roll off". This simply refers to the method by which vehicles and machinery are loaded onto large ocean shipping vessels for transport overseas. World Class Shipping is a leading provider of roro logistics services to individuals and corporations who wish to transport single or multiple vehicles....
Ferries, due to their width have a ratio to depth that is less than ocean going ships because the travel is expected to be short in duration and along a proven route that is mostly safe from ocean surface fluctuations.
It is true ferries have challenges to their stability, especially when passing by inlets where ocean waters mix with bay or coastal waters. A ferry can become unstable if hit with strong currents, but, most captains know their boats and the water they navigate and anticipate these currents.
I experienced and witnessed on ferries some very adept captains and crews as they travel across waters that become turbulent during storms or meet with incoming ocean turbulence. They primarily turn 'at angle' to the water rather than take it head on. That is not what happened here according to what is being reported.
From what I can discern, the government is stating a quick turn in the water 'created' a shift of weight on the ship that caused it to tumble. I suppose that is possible. Cars aren't anchored in place on ferries. And this ship was only recently in route so the amount of fuel would be significant while some would have been used for propulsion. I suppose there was enough room in the fuel tanks to cause problems with stability and it is very true ferries are precarious in water to begin with.
Without any insult to the hull or evidence of collision, instability would come into question. This type of ferry is not at all unusual in the world. It is seen in most countries where water transport occurs. Ferries also operate in shallower waters because of their water displacement.
So, we are looking at human error. I am not an expert on these waters. I do find it odd that unless the crew were completely novice to this route a sudden change in direction knowing the capacity of the ship, seems odd to me. But. That is me and not the officials overseeing the investigation.
Odd because it would be irrational to turn quickly without sincere reason of danger to do so. Briefly leaving prescribed routes or wandering ever so much out of a shipping lane isn't a dire emergency if here is no peril nearby. I think this sudden turn in open water is very strange.
