The next generation of warships might be virtually invisible to the human eye, thanks to the development of new stealth technologies.
These new technologies would in fact allow the ships to dodge roaming radars, put heat-seeking missiles off the scent, disguise their own sound vibrations and even reduce the way they distort the Earth’s magnetic field.
Wars throughout the twentieth century prompted advances in stealth technologies. Some of the earliest but most significant strides towards invisibility involved covering ships with flamboyant cubist patterns – a technique known as “dazzle painting”.
During the Second World War, the US military even worked out a way of using lights to make the brightness of a ship match that of the background sea.
Special paint and foam-coating have also been used to cover ships, which convert radio-waves into heat and stop radio waves being reflected, rendering the radar signals used to detect the warships useless.
The “stealthiest” ship that currently exists is Sweden’s Visby Corvette. Apart from being painted in grey dazzle camouflage and made of low-radar reflectivity materials, it also does not use propellers, which are the noisiest part of a ship. The vessel also has the lowest “magnetic signature” of any current warship.
But the next generation of warships could be truly invisible by exploiting “metamaterials” – artificially engineered structures first conceptualized by physicist John Pendry at Imperial College, London.
Metamaterials are tailored to have specific electromagnetic properties not found in nature. In particular, they can bend light around an object, making it appear to an observer as though the waves have passed through empty space.
According to Chris Lavers, senior lecturer in remote sensing and sensors technology at Britannia Royal Navy College, UK, “If optical and radar metamaterials could be developed, they might provide a way to make a ship invisible to both human observers and radar systems, although the challenges of building a cloak big enough to hide an entire ship are huge.”