In a small series, we would like to present the milestones that form the basis for the propulsion of our SVT train. This leads us back to the end of the 1st World War. At that time high performance engines for airships and airplanes were the main branch of the former Luftfahrzeug-Motorenbau GmbH. The most important customer during the war was still the German Army, but the Versailles Treaty prohibited development and production in the aviation sector. The young company, which was given the name Maybach-Motorenbau GmbH in 1918, saw itself stripped of its main sales market after the war. What to do now?
A flicker of hope is a report Karl Maybach received already before the armistice of Compiègne from his young colleague Richard Lang in mid-1918. In it Lang examines the market situation for high-speed diesel engines with an output of between 130 and 150 hp and also makes initial technical considerations. The result of his preliminary investigation is clear: Such an engine is not yet being produced. With this engine, Maybach could thus occupy an entire market segment and, in addition, there would be several areas of application for the engine: mainly rail but also boats would be conceivable – a vital perspective for the crisis-ridden company. The decision to develop the type G 1 engine was quickly taken (G stands for Gleichdruckmotor or Diesel).
In order to produce the test engine quickly and cost-effectively, the crankcase, crankshaft and connecting rod are taken over from the Mb IV a airship engine. However, a first version of the aluminium crankcase has to be destroyed and replaced by one made of grey cast iron, as the Entente Commission suspects that a new aircraft diesel engine is being planned. Such engines are prohibited by the Treaty of Versailles.
Despite these obstacles, the G 1 was ready for bench testing by the end of 1920. This was followed by disillusionment: the engine bearings in particular suffered from the higher requirements. The G1 is no more than what it was designed for: a first attempt. But even though this engine reveals the challenges of new technological territory, it is still an important cornerstone of later development. More on this soon.
Source and also an important reading tip for further reading (as of now only available in German): Wilhelm Treue, Stefan Zima: Hochleistungsmotoren. VDI Verlag: Düsseldorf, 1992. You can purchase the book at an antiquarian, it also is available at your trusted bookshop and online. We would like to point out in particular that an extended new edition of the book is planned.
Photos: MTU Friedrichshafen GmbH
First Diesel engine Type G 1 on the test bench