VK-105PF

The engine traces its ancestry to the French Hispano-Suiza 12Y, but by 1942 only the layout remained of the prototype. The PF index means "increased boost": supercharging was raised, the rated altitude lowered, and power near the ground grew by a hundred and fifty horsepower — where the air fighting on the Eastern Front actually happened. A ShVAK cannon passed through the cylinder bank vee and fired through the hollow propeller shaft — the arrangement that shaped the Yak-1, Yak-3 and Yak-9. The engine was light and compact but demanded careful attention to temperatures. On display is a sectioned engine with the motor-cannon, on a museum stand.