What are some sensory indications of an engine fire in flight?

When identifying the sensory indications of an engine fire in flight, it is crucial to consider the physical signs and symptoms that may be observed or felt during such an emergency. The presence of unusual sounds, vibrations or roughness, as well as smoke or flames, are all critical indicators that an engine fire may be occurring.

Unusual sounds can manifest as loud pops, hisses, or changes in the regular sound of the engine, suggesting that something is malfunctioning. Vibrations or roughness may occur as the engine experiences abnormal operation, leading to changes in the aircraft's performance and stability. Finally, visual indicators such as smoke or flames are among the most alarming signs, providing a clear indication that a fire may be present.

Since each of these sensory indications contributes to a comprehensive understanding of the potential emergency, recognizing them can aid pilots in taking appropriate and timely action to ensure safety. Therefore, the correct answer encompasses all of these indicators as they collectively signify the presence of an engine fire in flight.