Which of the following is not a required marking on center of balance markings?

The correct option is identified as the one that is not a required marking in center of balance (C.B.) markings, which is indeed the load type. In the context of air freight and aircraft loading, center of balance markings are critical for ensuring that the load is distributed appropriately within the aircraft to maintain safety and aerodynamic stability during flight.

C.B. markings typically include information such as the gross weight of the cargo, indicating the total weight that must be accounted for in the aircraft's load capacity. The C.B. marking itself is a required component that helps load planners and pilots quickly identify where the center of balance is located, ensuring that loading is performed in a way that maintains the proper weight distribution. Additionally, an arrow indicating forward of flight entry (FFE) is crucial for understanding the orientation of the cargo within the aircraft.

While the load type may inform loaders about the nature of the cargo, it is not a standardized requirement for C.B. markings. Instead, the primary focus of center of balance markings is on the gross weight, C.B. marking, and directional indicators such as the arrow for FFE, as they directly relate to the safety and performance of the aircraft in flight.