Feature
High Flyer! Words - Jeff Heywood ~ Photos – BMW Classic
On the 17th June 1919, Franz Zeno Diemer piloted the Deutsche Flugzeugwerke F 37/III biplane to a new world altitude record. The F 37/III was powered by a special engine, the BMW IV aero engine…
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he cruising altitude of modern airliners ranges from 10 to 12 kilometres. It is hard to imagine then, that a pilot managed to broach these heights a full 90 years ago. It was a BMW engine which, on 17th June 1919, propelled Franz Zeno Diemer to an altitude of 9,760 metres, 32,000ft! No human had previously piloted an aircraft to a greater height. This flight, in the summer of 1919 at Munich’s Oberwiesenfeld
44 BMW Car Club Magazine December 2021
airfield, proved the superiority of the ingenious yet simple concept of BMW’s high altitude engines. Diemer set out on his record flight from the Oberwiesenfeld on 17th June, in his DFW F 37/III, an altitude aircraft specially developed by Deutsche Flugzeugwerke. It was powered by the 23-litre, six-cylinder, two valves per cylinder water-cooled overhead camshaft BMW IV aero engine. The motor was
based on the tried and tested BMW IIIa, yet the new BMW IV engine had its bore and stroke increased by 10mm (taking it to 160mm x 190mm). With its extra capacity and a compression ratio of 5.5:1, the output went from 185 to 230hp, with a maximum continuous output of 250hp. Glorious flying weather saw the engine deliver consistently excellent performance on that Sunday, enabling Diemer to make
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