Reemphasizes Current Policy And Guidance, Air Carrier Responsibilities

The FAA has issued a Safety Alert For Operators (SAFO) for Part 121 operators addressing the potential safety impact of carrying and restraining heavy vehicle special cargo loads. The purpose is to reemphasize current policy and guidance concerning: weight and balance control procedures, cargo loading procedures, loading schedules and loading instructions.

According to the document, heavy vehicle special cargo loads are loads that may require special handling or restraint devices other than a Unit Load Device (ULD), such as a pallet or a container. The FAA says it is concerned about the procedures for carrying and securing heavy vehicle special cargo loads. This SAFO’s purpose is to heighten awareness regarding heavy vehicle special cargo loads, the air carrier’s approved weight and balance program, the FAA guidance provided for air cargo operations, and best practices for heavy vehicle special cargo loads and restraint.

"It is the air carrier’s responsibility to maintain the highest level of safety. Proper cargo loading is essential for safe flight operations," the document says. "The air carrier must have procedures to ensure that employees and vendors are properly trained in the process, the loading is properly completed, and that cargo restraints and loading devices meet the requirements of the approved program.

"Heavy vehicle special cargo loads, due to the non-standard and irregular nature of the cargo itself, require careful consideration of the limitations of the aircraft and the characteristics of the cargo to ensure safe operation of the aircraft. There are often overlapping limitations on the basic airframe and floor; cargo loading system attachment limitations; shoring requirements; strap material; and orientation in the forward/aft, lateral, and vertical direction. All of these limitations must be considered before defining a safe restraint configuration for special cargo."

According to the FAA, unsymmetrical tie-downs permit load distributions that may ultimately result in tie-down failure. Such a failure would result from the different load-deflection rates of dissimilar materials or of identical materials of different length. Any material subjected to a tension load will stretch. A longer length tie-down has more stretch potential than a shorter length tie-down. If two tie-downs of the same type and capacity are used to restrain a load in a given direction and one is longer than the other, the longer tie-down, with its greater stretch potential, will permit the shorter tie-down to assume the majority of any load that may develop. If the shorter tie-down becomes overstressed and fails, the longer tie-down would then be subjected to the full load and it, too, would likely fail. Therefore, symmetrical tie-downs should be as close to the same length as possible.

The FAA recommends that each part 121 air carrier should review its approved weight and balance control program with emphasis on heavy vehicle special cargo loads.

FMI: SAFO