On 14 October 1947, US test pilot Chuck Yeager did what many thought was impossible. Strapped into the seat of the Bell X1 rocket plane – painfully so, having broken two ribs a few days before in a horse-riding accident – Yeager became the first man to fly faster than the speed of sound.

While Yeager’s name may be the one celebrated in the record books, there were other pilots who got close – very, very close – to this challenging aerodynamic barrier in the years before. Some even lived to tell the tale. What is all the more impressive is the aircraft they flew were physically incapable of reaching the speed of sound. Just getting close could cause planes to break apart.

A handful of flights in Supermarine Spitfires – the single-seat fighter plane that helped win the Battle of Britain – were crucial in helping scientists understand the forces that would have to be overcome if a plane was able to fly faster than sound.