Kingfishers are small and surprisingly beautiful birds that are distinguished by a strong and long beak. What do these birds and Japanese high-speed trains have in common?

But these birds helped to solve one of the biggest problems of the Japanese bullet train!

When this train was first designed, the high speeds caused an atmospheric pressure wave to build up in front of it. As it passed through the tunnels, the wave caused a loud "sonic boom" at the exit. This clap was heard at a distance of almost 500 meters and greatly disturbed the nearby residents. The engineers had to find a way for the train to travel more quietly without sacrificing speed or using more energy.

This problem was particularly troublesome because it was tied to both the geometry of the tunnel and the speed of the train.

Unexpectedly, the chief engineer of the company, Eiji Nakatsu, found a solution to this problem. After attending an aeronautical engineer's lecture on birds, Nakatsu realized that studying bird flight would help him design the train of the future.

The engineer began to observe the kingfishers and noticed their impressive feature: in order to catch fish, they dived into the water at high speed and did it with little or no splash.

Then the scientist decided to design the front of the train similar to the head and beak of a kingfisher. This became a cardinal decision in the construction of bullet trains.

Data analysis showed that the ideal shape for these trains is identical to that of a kingfisher’s beak. Not only did this help to reduce noise and eliminate tunnel booms, but it also allowed the train to travel 10% faster using 15% less electricity.