Radner died on 24 March 2015 along with her husband Sascha Schenk and their infant son Felix, and colleague Oleg Bryjak, in the Germanwings Flight 9525 crash, which occurred near Prads-Haute-Bléone, Alpes-de-Haute-Provence, France. She and Bryjak were returning from performances of Richard Wagner's "Siegfried" at the Gran Teatre del Liceu in Barcelona.