Upon notification of an automatic warning device failure at a crossing protected by flaggers, at what speed can a train proceed?

When an automatic warning device fails at a crossing that is still protected by flaggers, the appropriate response for a train is to proceed at a normal speed without stopping. This practice ensures safety while also adhering to regulations in situations where flaggers are present to manage traffic and indicate the train's approach.

Flaggers are trained personnel responsible for signaling and ensuring safety at crossings, providing an essential layer of protection. Their presence implies that they are actively monitoring the crossing, directing any necessary actions, and managing traffic accordingly, which allows trains to maintain normal operations without the need for reduction in speed.

While other options may suggest various levels of caution - such as slowing down or stopping - the presence of flaggers allows for the safe continuation of the train at its normal speed, making it a practical choice within the operational guidelines provided for such scenarios.