GT 101 - Origins

Origins

As early as mid-1943 Adolf Müller, formerly of Junkers and then Heinkel-Hirth's jet engine divisions, proposed the use of a gas turbine for armored vehicle engines. A gas turbine was so much lighter than the 600 hp-class engines being used in the next-generation tanks that it would considerably improve their power-to-weight ratio and thereby improve cross-country performance, and potentially outright speed. There were problems with the gas turbine in this role, however.

In the case of a jet engine the hot exhaust from the turbine is used directly for thrust, but in the case of a traction engine any heat flowing out the exhaust was essentially wasted power. The turbine exhaust was much hotter than that from a piston engine, and turbine engines would thus have terrible fuel economy compared to traditional designs. On the upside, the use of inexpensive and widely available kerosene as fuel offset this disadvantage at least to some degree, so the overall economics of running the engines might end up being similar. Given the extreme problems Germany had with fuel supplies late in the war, use of low-grade fuels, no matter how much of it was needed and used, was actually seen as a major advantage, and the primary reason the Heereswaffenamt eventually became interested in the design.

Another problem was that the gas turbine engine only works well near a particular designed operating speed, although at (or near) that speed it can provide a wide variety of output torque. More specifically, turbines offer very little torque at low speeds, which is much less of a problem for a piston engine. In order to use a turbine in this role, the design would need to use an advanced transmission and clutch that allowed the engine to run at a more limited range of speeds, or alternately use some other method to extract power.

At first the Army was uninterested, and Müller turned to the design of an advanced turbosupercharger for BMW (it is unclear if this design saw use). When this work was completed in January 1944 he once again turned to the traction engine designs, and eventually met with the Heereswaffenamt in June 1944 to present a number of proposed designs for a 1,000-horsepower unit.