Switzerland 1932, glide Davos - Zurich, sailplane "Fafnir", pilot G. Groenhoff, by special delivery GA card with on each side franking, handwritten "No. 1" at the 23.1. from Davos via Zurich 23.1. to Basle 24.1.32; only 10 pieces known (32.2. b SF to Swiss Airmail handbook)