Initially designed by Ernst Heinkel Flugzeugwerke in 1925, the single-seat HD.27 with two mail compartments in the front of the fuselage was built in Sweden by Svenska Aero AB.
In the same year, the publisher Ullstein AG ordered an upgraded version of the HD.27 aircraft with an increased fuselage for high-speed newspaper delivery. A 400 hp Liberty motor was installed on the plane. (298 kW).
The mail plane was used for its intended purpose for three years and was destroyed in the hangar during a tornado.
More HD.27 was not built, a year later Ernst Henkel's company released a slightly larger, HD.39, aircraft with a BMW IV engine.

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