What should you do first in the event of a brake failure?

In the event of a brake failure, shutting down engine 1 is a critical initial action that can be taken to help manage the situation effectively. By shutting down engine 1, you reduce the thrust generated by that engine, which can assist in controlling the aircraft during ground operations, especially if it is not responding to braking inputs. This is crucial in scenarios where the brakes fail and the aircraft could move uncontrollably.

In general, the concept behind focusing on shutting down engine 1 is based on minimizing potential drag and maintaining some degree of control, as keeping both engines running could exacerbate the loss of control in braking situations. It also allows for the pilot to retain some maneuvering capability, while preparing for further actions required to manage the emergency.

The other actions, while necessary in specific contexts, do not provide immediate assistance in gaining control of the aircraft during a brake failure. For example, shutting down both engines or only focusing on egress procedures may not directly address the immediate control issues posed by brake failure. Similarly, contacting maintenance for instructions, although important for the overall safety and follow-up procedures, would not provide the necessary immediate response needed in a critical situation where control is essential.