What information does the Cargo Arm provide?

The selection regarding the information provided by the Cargo Arm highlights its function in calculating the balance of the aircraft. Specifically, it measures the distance from the Reference Datum Line (RDL) to the cargo's center of gravity. This is crucial for understanding how the cargo's placement affects the overall aircraft's weight distribution and stability.

Accurate weight distribution is vital for safe flight operations, as it impacts the aircraft’s center of gravity, which in turn affects the aircraft's performance, handling, and ability to remain stable during flight. By knowing the distance from the RDL to the cargo's center of gravity, aircrew can make informed decisions on positioning and securing cargo to maintain an optimal balance.

Other options provide valuable information but do not reflect the specific role of the Cargo Arm in distance measurement relative to the RDL. Weight measurement alone lacks the context of how that weight influences the aircraft's balance, while volume measurement does not consider weight distribution concerning the aircraft's center of gravity.