The next day, as the Germans were being driven back further, one of those planes – an Ilyushin Il-2 Sturmovik (Attacker) ground-attack aircraft – ditched in a lake south of the city. The crew survived but the aircraft was lost – one of dozens destroyed in the battle.

Seventy years later, that plane has surfaced on the other side of the world.

“This was recovered from the lake in the early 1990s,” says James Stemm, the director of aircraft restoration at the Pima Air and Space Museum in Tucson, Arizona. “It was bought by a US gentleman but he passed away, so his family donated it to us.”

Known as the “flying tank”, in total some 36,000 single-engine Sturmoviks were built – the greatest number of any military aircraft in history – and this is one of only a dozen survivors. It is surprising there aren’t more, it was one of the Soviet Union’s most important aircraft of World War 2. So important, in fact, that in an angry letter to armament factories in 1941 Stalin emphasised how vital the Il-2 was to the war effort: “Our Red Army now needs Il-2 aircraft like the air it breathes, like the bread it eats,” he wrote.