What is the function of a turn coordinator in an aircraft?

The turn coordinator serves a crucial role in an aircraft by indicating bank angles during turns. This instrument provides the pilot with a visual representation of the aircraft's attitude relative to its turn. It is designed to promote safe and efficient turning by displaying the rate of turn and whether the aircraft is in a standard rate turn, which is typically a turn of 3 degrees per second.

When making sharp turns, it also helps pilots maintain appropriate bank angles, which can prevent stalling and help ensure that the aircraft remains in controlled flight. This is particularly important during maneuvering flight to ensure that the aircraft maintains adequate performance.

The other options relate to different functions that are not associated with the turn coordinator. For example, measuring altitude changes corresponds to altimeters, regulating fuel flow is the role of fuel gauges and management systems, and monitoring engine temperature is performed by engine instruments. Thus, the specific function of the turn coordinator is accurately reflected in its indication of bank angles during turns.