 Stockhausen had dreams of flying throughout his life, and these dreams are reflected in the Helikopter-Streichquartett (the third scene of Mittwoch aus Licht), completed in 1993. In it, the four members of a string quartet perform in four helicopters flying independent flight paths over the countryside near the concert hall. The sounds they play are mixed together with the sounds of the helicopters and played through speakers to the audience in the hall. Videos of the performers are also transmitted back to the concert hall. The performers are synchronized with the aid of a click track, transmitted to them and heard over headphones (Stockhausen 1996c, 215).
