The 588th Night Bomber Regiment of the Soviet Air Force, known as the "Night Witches" (Nachthexen) by the Germans, was composed almost entirely of women between the ages of 17 and 26. They flew canvas-covered Polikarpov Po-2 biplanes — crop-dusters — at night, making bombing runs at extremely low altitude. They were called Night Witches because their engines would cut out in a glide, making them eerily silent, and the Germans thought they could hear the whooshing of their wings like broomsticks. The Night Witches flew over 23,000 sorties and dropped 3,000 tons of bombs. Their aircraft were so slow that German fighter pilots found them nearly impossible to shoot down — the jets and high-speed props of the Luftwaffe struggled to engage targets moving at 60 mph. Over 30 Night Witches were awarded the Hero of the Soviet Union title. Their commanding officer, Marina Raskova, was herself a famous Soviet navigator who had personally convinced Stalin to allow female pilots.