Search This Blog

Friday, 9 October 2015

Safe at port or safer at sea?

Land is dangerous 1(4)
Personally I as a captain (of my small boat) feel the safest when the boat is away from land and the less control I have over the boat (as a result of for example bad weather) the further away I want to be (but a nautical mile or two is often for me enough). My respect for proximity to land stems form that I have seen the problems that rock-ship interactions can have, but also because I know how the effects of bad weather can be turned in to dangerous forces by the closeness to land such as when shallow water makes a seemingly small wave turn into a wall of water or when high wind speeds are turned into erratic gusts by land formations.

Land is safe 1(1)
At the same time I see the logic in rules and regulations that define port as the safest place to be. This is exemplified in regulations such as:
- the safe return to port concept for passenger ships (because a port is the only place where many people can debark safely), or
- when some types of work are only allowed to be performed if the ships is at port.

Land is dangerous 2(4)
My research clearly show another dangerous aspects of land. Ships are the most susceptible to many security threats in ports or close to land as a result of low speeds and high density of ships. Civilian examples of this include piracy in the Malacca Straits and off Nigeria and military examples include the suicide bombing attacks performed on naval ships (Hans Liwång, Survivability of an ocean patrol vessel – Analysis approach and uncertainty treatment, Marine Structures, Volume 43, October 2015, Pages 1-21) of which the attack on USS Cole probably is the most know example.
Land is dangerous 3(4)
Another example of safe at sea is tsunamis were you at port or even on land potentially is a sitting duck. However, at sea a potentially devastating tsunami may raise the sea level but can pass by unnoticed.

Land is dangerous 4(4)
Almost all (>90%) personal injuries onboard ships in the Swedish statistics from the years 1995-2010 happened in the harbor area and about 60% when a ship hit a man-made structure above water (kay, dock, bridge).

Consequently, I see land as a dangerous thing for boats. It is a 4-to-1 victory!

But then reality show me that it isn’t that simple
The container ship El Faro sunk east of theBahamas October 1 2015 after losing propulsion while attempting to get away from the hurricane Joaquin along the ship's route from Jacksonville to Puerto Rico. All reports indicate that the 33 persons on board died in the accident. Loss of power makes the waves much more difficult to handle which in this case probably led to the reported list and water intrusion through an open hatch. Therefore, in this accident being at sea introduced several uncertainties which this time interacted in such a way that the ship sunk.
Consequently I have to update my statement from above about land being dangerous:
At sea a ship is in its right element and even if something goes wrong you most often have the time and possibility to fix it before it gets dangerous. However, at sea the uncertainties are high and how and when depends on many aspects.
The land it self introduces several new potential hazards, however the situation or consequences are generally more controllable or predictable.

So if you like predictability stay close to land, but if you really want to use the boats capabilities be at sea.

No comments:

Post a Comment