FAA Powerplant Written Practice Test

What is a defining characteristic of the Rotax 914 engine?

1. It is a two-cylinder engine

2. It has water cooled heads and air cooled cylinders

3. It is a two-stroke engine

4. It has no cooling mechanism

The correct answer is: It has water cooled heads and air cooled cylinders

The Rotax 914 engine is known for its unique cooling configuration, where it features liquid-cooled (water-cooled) cylinder heads combined with air-cooled cylinders. This hybrid cooling system allows for better thermal efficiency, particularly in high-performance applications. The water-cooled heads help to efficiently dissipate heat in the areas most prone to overheating, while the air-cooled design of the cylinders helps reduce weight and complexity. This characteristic makes the Rotax 914 suitable for various aviation applications where reliability and efficient cooling are critical. The other options do not accurately describe this engine, which is a four-stroke engine rather than a two-stroke, and it does indeed utilize a cooling mechanism instead of lacking one entirely. This indicates the importance of understanding the specific design and operational features of the Rotax 914 engine, which is a popular choice in light sport and experimental aircraft.