In 1942 Ferdinand Porsche was battling with the larger firm of Henschel for a Wehrmacht contract. Impressed by the work done by Porsche on various smaller vehicles such as the Kubelwagen and KdF Wagen; later known as the Volkswagen, Hitler was willing to give the designer more opportunities. So in May 1941 Porsche was given a chance to design the ultimate off road vehicle...a tank. In the 1940's, the performance of engines was much better than it had been twenty years before, but were still rather anemic given the tasks they were asked to do. So big tanks could go over three times faster than they did in the first world war, but still struggled to hit 30mph on flat terrain. Porsche had a great idea...make a hybrid.
The idea was nothing new. There had been gas/diesel-electric hybrids for a while. This started in shipping at the turn of the 20th century and continued with the advances in submarines. By the 1920's smaller diesel electric locomotive engines started to pop up with this. Porsche figured this idea could be adapted to a vehicle. By using small gas or diesel engines to drive electric motors, Porsche hoped to fix several problems. Gas and diesel engines do not make power in a linear way. They have a power curve where they make more power at certain engine speeds than others. At this time, tank engines made power in medium speeds. There was a lag time to get into the "power band" as the engine revved, and the driver would have to compensate for the surges and lags with varying engine speed. On an electric engine, the power is all there from the start through the maximum vehicle speed. This would allow for a quicker tank that could maneuver more quickly from a stand still.
Porche's design was designated the VK4501P, not very flattering or catchy. It used two engines to drive an electric motor on each side. However, the drive-train was very typically German in its complicated design and therefore tended to breakdown easily if not maintained. It was also so alien to crews that they found it confusing to maintain and repair. Also at the time the design just could not be produced as fast when it was most needed...to win the war. Therefore the design was passed over and Henschel won the contract for what would be known as "The Tiger Tank". However, Porsche would try the same design again, but with diesel engines. This too would fail, again losing to Henschel again for what would be known as "The King Tiger". A few of the prototype chassis for both would be used for specialized anti tank killers, but with conventional engine systems.
So if you see a Porsche hybrid going down the road sometime, you know it is because the owner wants to be "green". Seventy years ago it was because the owners wanted to kill people and blow up stuff.
|A rare photo of Porsche Hybrid prototype that lost out to be the Tiger tank|
|The Tiger 1 protoypes were used to build this...the Elefant (Elephant) tank destroyer|