Remote Control Operator (RCO) Practice Test 2025 – Your All-in-One Guide to Exam Success!

In the context of remote control operations, the loss of communication between the Remote Control Terminal (RCT) and the Remote Control Locomotive (RCL) is indicated by a visual alert—specifically, a red light flashing. This is a critical safety feature designed to provide immediate visual feedback to the operator that there is an issue with communication. The flashing red light serves as an urgent signal that the operator should take action, assess the situation, and possibly halt operations to ensure safety.

While other signals like warning sirens can be associated with alerts in different contexts, they are not typically the primary indicators for communication loss in remote control systems. Similarly, an accelerating locomotive would indicate a failure in control rather than a direct loss of communication, whereas disabling the remote control would be a response to a failure but not the indication of communication loss itself. Thus, the flashing red light succinctly conveys the critical message about the state of communication between the RCT and RCL, making it the correct answer.