How are the pilot's controls for exterior lighting described?

The pilot's controls for exterior lighting being located on the lower right instrument subpanel and functioning as circuit breakers highlights an important aspect of cockpit design and functionality. These controls allow the pilot to manage exterior lighting systems directly, providing both control over the lighting configuration and protection for the electrical circuits associated with those systems.

In aviation, circuit breaker designs are crucial because they not only serve as switches for activation but also prevent overcurrent situations by automatically cutting off power if a fault occurs. This dual function enhances both safety and operational efficiency, ensuring that the pilot has immediate access to switch the lights on or off, as well as the ability to respond to any electrical issues.

The other options reflect different systems and configurations that do not align with the established layout of pilot controls for exterior lighting in the context of the T-54A. For instance, external lighting being integrated into the primary flight display or controlled by automated systems would not provide the same level of direct control and situational awareness that a physical control panel allows. Therefore, the subpanel configuration remains the preferred method in many aircraft designs, including the T-54A, for handling critical items like exterior lighting.