4 LBS = 5 HP?

Looks fascinating, but 15,000 rpm? Lots of wear and tear.
One would think a second chamber and a second "piston" would eliminate vibration and a need for the counter weight.
If this takes off it could replace regular piston engines in a few years.
(And perfect for aux generators on electric vehicles, low weight and all)

I am very familiar with Wankel type or rotary piston engines. And I had to learn it the hard way, as I had a car with a Wankel engine. The 115 HP, 4 door sedan NSU Ro 80 (now Audi). A great car, far to advanced for its time but the engine was not very reliable and most of all not full power steady, a very bad behaviour for me as a young driver and even more for the German Autobahn (no speed limit !). Means, the engines did not last very long.



When two Ro80 cars met on the road, the drivers raised their fist as a greeting. The amount of fingers raised from the fist counted for the numbers of engines already used up in this car. Good thing was, your engines never left their warranty . They always died before. That was the main reason Audi stopped production of this car. And presently I have a EASA and FAA certified 56 HP Wankel engine in my powered glider.



This modern Wankel engine is much more reliable than my old Wankel car, 40 years ago but as all rotary piston engines, it has some systemic "problems". It is a kind of 2 cycle engine where lubrication oil is used for sealing the rotating combastion chamber against the side walls. Means, the lub oil is burned during the combastion process. Which also means, this type of engine will always have problems complying with onroad emission rules.

The other problem is the internal piston cooling, as it can only be done by and with air and third, the high RPM with only narrow RPM range for sufficient torque. For an aircraft engine no problem at all but for onroad purposes with many problems and complicated engine/gear systems to deal with. The best use for a Wankel engine besides being used in aircrafts (because of its small size and very low vibration) is being used as a generator or pump with constant high RPM.

This liquid piston engine will have the same systemic problem areas. But if I understand this video correctly, the rotary piston has no sealing strips as the Wankel had in the 3 corners of the rotary piston. Means, even more sealing with lub oil or rotating the piston will be a machining process, as the tolerances have to be very small. And EPA will most likely not like this type of loss lubrication.

But this little engine would probably be great for RC model planes and helicopters. Much better than those little OS Max 2 strokes. They would fit perfectly in one of your helicopters Carl.

Carl, how about one of those, the OS max Wankel. My youngest son had one in his RC plane. Did not last very long. Ended up one feet deep in soft ground after vertical impact. The engine did not survive . But had a great sound, when still alive.

After that crash, my son transfered to 4-strokes. Much better sound and no more nitromethan fuel (awfull stuff). Now he is on electric engines only.

When I was a young boy, I had little model glider with a Cox pee wee nitro engine and no RC (did not exist), just a clockwork for the airbrakes to bring the plane down after a preset time. Pretty stupid toy, I must say.

Since I am 14 years old, I prefer planes or helos with a cockpit to sit in and a stick for direct control .

A guy in our gliding club just bought one of those, A glider with an EASA certified retractable jet engine. Climbs out like a lame duck but makes a noise like a Lear Jet.

Cox Pee Wee, been there, done that.
Surprised those engines took the abuse at the high RPMs they spun at.
My finger tips also took the abuse of trying to start them things.

Then, with a few fingertips left, I graduated to the "diesel" engines, more cutting power and more tempremental, great combo for a 12 year old boy.

Fortunately I discovered girls, beer and motorcycles a couple of years later, after that nothing ever went wrong.

Still have a scar in one of my fingers from starting one of theses nasty beasts...