So why didn’t helicopters – which were much quieter than the earliest generation of jet airliners, and which can take off and land vertically on a fraction of the space needed for conventional aircraft – fly in to plug the gap?

It may seem like an ingenious solution – imagine taking a flight to the south of France from a heliport in the centre of the city. Unfortunately, creating something that marries the flexibility of a helicopter with the passenger capacity of an airliner has been a monumental struggle. Physics keeps getting in the way – but as technology improves we may find solutions to overcome the problems.

Short, stubby and deafening

There was one aircraft that got closer than most – it even flew. The Fairey Rotodyne was a late 1950s attempt to design the helicopter airliner. It had a giant rotor on top of the fuselage, and a pair of short stubby wings, which each carried a jet engine that powered propellers and helped generate lift for the main rotor. The Rotodyne was intended to host as many as 40 passengers.

The Rotodyne was designed a few years after jet airliners had entered service. Already, the space needed for airports was becoming an issue. But, as the Royal Aeronautical Society’s Mike O’Donoghue says, there were serious technical issues its creators found impossible to overcome.