What must occur for a brake temperature readout to change from red?

The correct answer is that the BTMS reset button must be pushed to change the brake temperature readout from red. In the PSA Airlines Canadair Regional Jet Systems, the Brake Temperature Measurement System (BTMS) is designed to monitor the temperature of the brakes during operation. When the brake temperature exceeds a certain threshold, the system will indicate this by displaying a red readout, signaling that the brakes are too hot and may require attention.

Pressing the BTMS reset button prompts the system to clear the red indication, allowing it to reset the readout based on the current conditions of the brakes. This action is necessary because the system does not automatically reset simply because the aircraft has landed, the brakes have cooled down, or because maintenance has inspected them. Without a reset, the system will continue to indicate the overheated status until manually cleared.

Thus, understanding the function of the BTMS reset button in the operational procedure is critical for flight safety and effective aircraft management.