Managing information

Up 7.1 Soccer score 7.2 To catch a plane 7.3 Supertanker 7.4 Management accounts

7.3 Supertanker

If you are the captain of a supertanker sailing down the English Channel, any decision you take now about changing the direction of the ship will not happen for about 15 minutes, because it is so heavy. Thus the information relevant to you is that required for forecasting and where you have been, and where you are now, are only important in knowing where you will be.

In practice, since the ship is so heavy it is not easily manoeuvrable and the decision on the course will be have to be made many hours in advance and the necessary information is required then. You will agree this with the Navigating Officer and he/she can give the helmsman the necessary commands.  Since the decision on the course is made well before a change in direction, there is no need to haul the Navigating Officer out of bed to make it.  A few hours will make no difference – assuming you have recognised the need to plan!

Contrast this with the situation that a ship has altered course and could collide with you in 10 minutes.  You would wish to know of this risk immediately in order to take appropriate action, such as telling the other ship to change course.

In both the above situations it is the helmsman who needs the information promptly!

However, you don’t wish to know the position of all ships in the area, that job is delegated to the Navigating Officer.  The information relevant to you is about those ships which could be a risk and where you have to make a decision.

If the Navigating Officer told you not to worry, as the ship on a collision course would miss your ship by 38.236m, you might be a bit suspicious. How could he possibly calculate the figure that accurately, given the uncertainties in the speed and direction of the other ship? You would be right in suspecting that he really didn’t understand the figure he was providing and the uncertainties inherent in the calculation.

However, you do want to know about the risk of collision.  What’s the most accurate information?  Your own course and speed. Knowing this, and the position of the other ship, which can be determined with reasonable accuracy from radar, you can determine the range of speeds and directions for which the ships could collide.  If the course and speed of the other ship lies in that range, you had better give the captain of that ship a call.