What requirement must all cranes manufactured after November 2011 meet regarding the drum rotation indicator?

Cranes manufactured after November 2011 are required to have a drum rotation indicator that is visible to the operator. This is crucial for ensuring safety and operational efficiency, as the operator needs to have real-time awareness of the drum’s position during lifting operations. If visibility is an issue, alternative solutions like mirrors or cameras must be in place to relay this critical information to the operator.

The requirement for visibility emphasizes the need for operators to be fully aware of their equipment's operation to prevent accidents and ensure safe crane usage. Accessing this indicator information during operation keeps the operator informed about the status of the lifting mechanism and helps in making informed decisions.

Other choices do not align with safety standards set for crane operation. Automation of the drum rotation indicator is not mandated; rather, visibility is the focal point. Moreover, not requiring visibility or only checking the indicator during maintenance would compromise safety, as operators need continuous operational awareness while using the crane.