What is the main reason for using a carbon brake system in aircraft?

The main reason for using a carbon brake system in aircraft is to provide better stopping performance and reduced weight. Carbon brakes offer several advantages over traditional metal brakes, including superior thermal resistance and a lower weight, which is crucial in aviation where every pound matters. This enhanced stopping performance is attributed to the carbon material's ability to withstand high temperatures generated during braking, which ensures consistent braking power and reduces the likelihood of brake fade. Additionally, the lightweight nature of carbon composites contributes to overall aircraft performance and fuel efficiency by reducing the aircraft's total weight.

The other options, while they may have relevance in different contexts, do not align as closely with the primary benefits of carbon brake systems. Reducing noise levels, cooling the engine, and improving fuel efficiency are not the primary functions or advantages of carbon brakes in aviation. Instead, the main focus of using carbon brakes is their ability to provide effective braking while minimizing the weight impact on the aircraft.