What colors denote mineral-based and phosphate-ester hydraulic fluids?

The identification of hydraulic fluids is crucial in aviation maintenance and safety practices, as using the wrong type of fluid can lead to system failures or hazardous situations. Mineral-based and phosphate-ester hydraulic fluids are color-coded for easy recognition.

The correct answer indicates that red is used to denote mineral-based hydraulic fluids, while light purple signifies phosphate-ester hydraulic fluids. This color convention is important because it helps technicians quickly identify the correct hydraulic fluid to use based on the system requirements, preventing potential cross-contamination and associated risks.

Other options present different combinations of colors that do not align with the established color codes in the industry, which can lead to confusion and maintenance errors. Therefore, understanding and recognizing these color codes is vital for maintaining aircraft safety and functionality.