Which of the following is included in engine inspections?

The inclusion of functional checks of certain systems in engine inspections is critical for ensuring the reliability and safety of the aircraft. Engine inspections go beyond just visually assessing the engine's exterior; they involve a thorough evaluation of various parameters and systems related to engine performance. This may include checking the fuel flow, oil levels, pressure readings, and operational output to ensure that all components are functioning as intended.

Functional checks are essential for identifying potential issues that could compromise the engine's performance and, consequently, the aircraft's overall safety. By performing these checks during inspections, maintenance personnel can detect early warning signs of malfunction or wear, enabling timely repairs or adjustments.

In contrast, while checking fuel efficiency is important for overall aircraft performance, it is not directly part of the engine inspection process. A visual inspection of the cockpit, although crucial for pre-flight checks, falls outside the scope of engine inspections. Lastly, testing landing gear mechanisms relates to different aspects of aircraft maintenance and safety, separate from engine functions. This distinction helps clarify why the focus on functional checks is not only correct but also essential for comprehensive engine inspections.