Heinkel He 172

The Heinkel He‑172 was a German single‑engine, low‑wing monoplane developed in the early 1930s by the aircraft manufacturer Heinkel. First flown in 1931, the He 172 served primarily as an experimental and research platform for the Luftwaffe, allowing engineers to evaluate aerodynamic concepts, propeller performance, and new powerplants. Constructed of mixed wood and metal, the aircraft featured a fixed, spatted undercarriage, an enclosed cockpit with dual controls, and a 120 kW (160 hp) Argus As 10C inverted‑V12 engine driving a two‑bladed metal propeller. Its relatively clean wing profile, absence of external bracing, and modest weight gave it a maximum speed of about 210 km/h (130 mph) and a service ceiling of 5,500 m. The He 172’s most significant contribution was its role in the development of advanced training techniques and the testing of low‑drag fuselage shapes that later appeared on World War II fighters such as the Heinkel He 100 and the Messerschmitt Bf 109. Operational trials continued at Heinkel’s Rostock‑Wietlitz test centre until 1936, when the type was retired and its airframes scrapped. Though only a handful were built, the aircraft demonstrated the value of purpose‑built testbeds and helped shape German aeronautical engineering during a period of rapid technological progress.