Have you noticed how ships, both large and small tend to be painted a different color under the water, most often it is red but actually nowadays you can get any color you like.
A lot of people may think that there is no apparent reason for a ship to be painted in an area which is always under the waterline where nobody sees it. Either way, have you ever wondered why most of the ships are painted with red color on the bottom?
Well, one of the answers is tradition. Shipping is a tradition-oriented industry and as you must be aware that all ships are called ‘She’ based on an old nautical tradition. But tradition is not the only reason for painting the ship’s bottom red, there is science behind it.
The reason for it goes back to the earliest days of sailing ships, back in those days wooden sailing ships would travel around the world slowly, a combination of their slow speed and rough hull made them an ideal breeding ground for underwater growth. Just take a look under a pier, you will see the sort of growth these ships used to suffer, we are talking about the barnacles, worms, seaweed and other micro-organisms.
Now you might wonder, what’s the issue with such growth on the ship’s hull? Well, this muck not only impairs the vessel’s structure but also increases the drag. That means the ships wouldn’t move as fast as they could, or they might use more fuel while getting through the water.
The sailors in those early days, used to cover the hulls (the part sitting in the water) of their boats/ships with copper paint to protect the vessel from unwanted wood-eating worms, barnacles, sea-weed, etc. It was the copper that added a red tint to the paint. Thanks to this substance, ships could stay intact and wouldn’t be weighed down by all the unwanted stuff collected on the hull below the waterline.
Nowadays, you can add special ship-protecting ingredients (Anti-fouling coatings) to any kind or color of paint. But the hulls are still painted red to honor and maintain the old nautical tradition.
Another reason can be traced in the contrast of red hull to the sea water, which demonstrates if the ship is overloaded. The more cargo a ship is carrying, the deeper it enters the water and the red color is the demarcation line (Plimsoll line).
In the same context of ‘contrast’, the red color at sea can be very easily captured by passing-by helicopters in case of an emergency.
Here is a detailed video on this interesting subject: