The car designer who turned a sailfish into a supercar

How would your boss react if he had to sign off for an expensive stuffed fish you’d bought on a whim on your holiday? Most of us would probably answer “not very thrilled”. But Frank Stephenson’s boss is not your average boss; his workplace is not your average workplace; and the fish? Well, that’s not your normal fish either.

Stephenson is design director of McLaren Automotive, the carmakers behind a range of highly prized, high-priced cars. While on holiday in the Caribbean, he noticed a sailfish on a wall in the resort where he was staying. A man working there told Stephenson that he was proud to have caught the fish because it was so fast. Stephenson was intrigued – he began doing some research on the species to find out why it was so quick.

On the way back to London, Stephenson stopped off in Miami and went down to a local fishing village, where, in a stroke of luck, a local fisherman had just caught a sailfish. He bought it, sent it downtown to get it stuffed and eventually got it delivered to the scanning department of the McLaren Automotive aerodynamics laboratory in Surrey – where the carmakers set to work trying to learn the secrets of the super-speed fish’s abilities. It’s just one of a number of recent initiatives by automotive companies to try and learn from techniques that have been used in nature.

The sailfish is a kind of turbo swordfish; one that has been clocked swimming 100 m in around half the time it takes Usain Bolt to run it. They are capable of these bursts of breath-taking speed in order to chase down the small, fast-swimming fish they eat. The analysis revealed that the scales on the sailfish’s skin generate little vortices that result in the fish being enveloped in a bubble of air instead of denser water. This reduced drag allows the fish to move even faster.

Evolutionary design

McLaren’s designers applied the same texture as the scales of the sailfish to the inside of the ducts that lead into the engine of their P1 hypercar. This increased the volume of air going into the engine by 17%, improving the car’s efficiency: the P1 has hybrid engines creating 665 kW and thus needs large amounts of air pumped into the engine to help combustion and engine cooling.

The P1 also borrowed from the sailfish little ‘diplets’ on the torso of the fin where it meets the tail fin that the fish uses to straighten out the flow of pockets of air and water that move past it. This, Stephenson says, made the car more aerodynamic.