I dunno....

Here are my sources in "A Dance with Death," which are interviews with the real pilots condensed into a book. Every place she is mentioned by the female pilots, navigators, mechanics, etcl... They mention her as Irina.

Page 33: "But the aircraft behind me, piloted by Dusya Nosal, was caught by the enemy fire. She was killed in her cockpit. Her navigator, Irina Kashirina, in the back cockpit knew how to fly and took over the controls..."

Page 34: "One was Irina Kashirina, who had landed the aircraft with the dead pilot."

Page 75: "They said, 'No, Dusya Nosal was hit in the temple with a bullet, and the navigator landed the plane with her dead in the cockpit.' Soon after, her navigator, Irina Kashirina, also perished in battle."