Heinkel HD 36

The Heinkel HD 36 was a trainer developed in Germany in the 1920s at the request of the Swedish Air Force, which was looking for a new trainer. The air force had evaluated the Heinkel HD 35 and found it underpowered, so Heinkel answered with a development that used the Mercedes D.III engine and dropped the third cockpit of the HD 35 and HD 21. The single example built by Heinkel was tested and, being still not quite satisfactory, was modified by the air force workshops until the problems were largely eliminated. Those workshops then built two batches of ten aircraft, delivered in 1928 and 1930 as the Sk 6. Constant engine trouble led to flight restrictions and finally to Armstrong Siddeley Puma engines being fitted, giving the S 6A, but the type was soon dismantled.