When you think of a rotary engine, you probably think of a Wankel engine, the kind of engine that Mazda used to put in their coolest cars back in the day. They also put it recently in the MX30 REV, but this one is a sort of plug-in hybrid where the rotary engine performs the most humbling task imaginable, it's a range extender. Now, the important thing about the Wankel is that it was a success in terms of power-to-weight ratio and smoothness; in terms of everything else, it was a failure. Fuel economy, emissions, low-end torque, longevity—it didn't really do any of these things well. It was and still is a very fun and very exciting engine, so we'll call it a beautiful failure. A rotary engine is inherently superior in this regard because we need the output of the engine to be rotation. So we can connect the engine to the transmission and the wheels, which are both rotation. So if the internals of the engine already rely on rotation like the rest of the vehicle, we completely eliminate a lot of problems, a lot of parts, and a lot of bulk and mass. So, according to physics and common sense, the ultimate internal combustion engine should be a rotary engine. But it shouldn't be a Wankel. It should be a rotary vane engine. Basically, we have a circle that's spinning inside an ellipse, and we have four vanes that extend in and out of the housing. As the vanes spin, they change the volume of the spaces that they create. We have air coming in through the intake ports. As the vane spins, it pushes air into a smaller and smaller space, which of course compresses the air. When the air is fully compressed, we add the fuel. And then we use a spark to ignite the fuel-air mixture. As the combustion mixture expands, it pushes the vane, which spins the inner circular rotor assembly, which creates rotational torque output. As the vane spins further, it pushes the exhaust out through the exhaust port. We have four combustion events for a full 360-degree rotation of the circular rotor. In a Wankel engine, we have one combustion event for one complete rotation of the rotor and three rotations of the eccentric shaft. In a traditional four-stroke piston engine, we need 2 complete rotations or 720 degrees of crankshaft rotation for just one combustion event. This means that the rotary vane engine significantly outperforms both the Wankel and the traditional one. But high power is just one of the features. It is just one item on the list of benefits. Just like a Wankel engine, the rotary vane engine does not need a cylinder head, crankshaft or connecting rod and there is no reciprocating. So we have a very powerful, very light, very smooth and very compact engine compared to a piston engine. But the rotary vane engine is even simpler and is even smoother than a Wankel. Another benefit is that the rotary vane engine is not just a powerful machine, it is a torque monster and is much better suited to creating massive torque at low revs than a piston or rotary engine. In this respect it is also very similar to an electric motor. We have two things that both the Wankel and piston engines can only dream of. A giant, constant lever arm. And our combustion force acting right at the end of that lever arm to achieve maximum torque. The large distance from the vane receiving the combustion pressure and the center of the rotor where the torque is produced means that even a small engine with a small rotor will have a very large lever arm and massive torque. And this lever arm is constantly there, it doesn’t move or change its position relative to the combustion pressure force. And it’s constantly present in the same position throughout the entire progression of the combustion event. This leads to a long-lasting and very broad torque peak throughout the combustion event. And remember that we don’t have to wait 450 degrees of rotation for another combustion event. In a vane engine, the end of one combustion cycle is immediately followed by the beginning of another. We need a four-cylinder piston engine to achieve the effect of a single rotary engine.