FAA Powerplant Written Practice Test

What feature does the experimental, non-certified version of the Lycoming O-233 series engine include?

1. Dual ignition systems

2. Capability of running on gas or unleaded automotive fuel

3. Variable pitch propeller interface

4. Integrated electronic monitoring systems

The correct answer is: Capability of running on gas or unleaded automotive fuel

The experimental, non-certified version of the Lycoming O-233 series engine includes the capability of running on gas or unleaded automotive fuel. This feature is significant because it demonstrates the versatility and adaptability of the engine in utilizing different fuel types, which can be particularly advantageous for experimental aviation. This flexibility can help reduce operational costs and improve fuel availability for pilots operating in various environments. In contrast, while dual ignition systems are a standard feature in many certified aircraft engines to enhance reliability and safety, their presence is less distinguishing for an experimental version specifically. The inclusion of a variable pitch propeller interface is more common in engines designed for specific high-performance applications rather than in an experimental context where simplicity and cost-efficiency may be prioritized. Integrated electronic monitoring systems can enhance engine performance monitoring but are not a defining feature exclusive to the O-233 series, especially in its experimental edition.