The Rotorway Aircraft Company Inc., of California, began building small helicopters with Mercury and Evinrude engines. Later the helicopters were the Exec and Scorpion.

-In 1967 it presented its own engines, starting with the 100 HP RW-100, also suitable for small airplanes.

“RW-100”

-It had four horizontally-opposed, liquid-cooled cylinders. Normally they were naturally aspirated, and had dual ignition.

-They could be used for applications such as puller or pusher. This engine was only sold as a kit and was offered until 1984.

-The RW-133 also had four opposed cylinders two by two but in a vertical position, for use in helicopters.

“RW-133”

-Normally it gave 133 HP when it was simply aspirated or naturally aspirated, at 4,500 rpm. Turbocharged it reached 160 HP.

“RW-145”

-The RW-145 giving145 HP was manufactured between 1981 and 1986. It was sold as a Kit, like all of the brand's engines. It was turbocharged.

-The rest of the characteristics were identical to the previous engines.

-The RW-152, from 1986, gave 152 HP, with the same arrangement of four horizontally-opposed and liquid-cooled cylinders.

-The actual displacement was 2,660 cc and the power of 152 HP was given at 4,400 rpm. There was the vertical version for the Exec and Scorpion helicopters. This was the RW-152-D version.

“Two RW-152 views”

-The RI-162F, the first to change the reference from RW to RI when it became part of the new Rotorway International company. It gave 162 HP.

“Rotorway RI-162F”

From Appendix A1/6: In 2008, a small Rotorway helicopter was offered to the market in a homebuilt kit, the Talon A600 model.

-It is equipped with a RI600N/147 HP engine.

“Rotorway RI600N engine”

-With the ACIS device as a supercharger, it maintains the 147 HP at a higher altitude. Providing exactly 167 HP at 4,250 rpm with ACIS, it is then renamed RI600S/167 HP.

-It is water cooled, wich is one of its particular details. Both models have a displacement of 2,659 cc.

-It is a multi-fuel engine as it can operate with 95, 98 and 100 octane, unleaded, the latter being of the AVgas type.