What component cools hydraulic systems 1 and 2?

The component responsible for cooling hydraulic systems 1 and 2 in the CRJ550 is a ram air heat exchanger. This heat exchanger utilizes airflow during flight to dissipate heat generated by the hydraulic fluid as it circulates through the system. By converting thermal energy into kinetic energy, the ram air heat exchanger is efficient in maintaining optimal hydraulic fluid temperatures, which is crucial for the proper functioning and reliability of the hydraulic systems.

The hydraulic systems must operate within a specific temperature range to ensure they provide reliable performance, so the cooling effect of the ram air heat exchanger is critical, especially during hot weather or high-demand operations.

The other options, while they may serve cooling functions in different contexts, do not specifically apply to the hydraulic cooling system in this aircraft model. For example, a water-cooled radiator is generally designed for engine cooling, an oil cooler serves to cool engine oil or transmission fluid, and a thermal management system may refer to a broader range of temperature regulation across various systems rather than specifically addressing hydraulic fluid cooling.