Heinkel HE 12

Imagine: Wikimedia Commons

Another mail plane variant from 1929, the HE 12 continued Heinkel's civil aviation strategy with an efficient single-engine design. Spanning 16.8 metres and achieving 215.7 km/h, it served scheduled air mail service with adequate capacity and reliable performance. The mail plane roles of the 1920s and 1930s represented important early commercial aviation applications.