Federal Aviation

MMEL Policy Letter (PL) 108, Revision 1


October 17, 2011


All Region Flight Standards Division Managers
All Aircraft Evaluation Group Managers


Manager, Air Transportation Division, AFS-200

Reply to Attn of:

Manager, Technical Programs Branch, AFS-260


Carriage of Empty Cargo Handling Equipment




PL-108, Original, dated October 10, 2001


To provide standardized a standard relief statement MMELs that allow for the carriage of empty cargo handling equipment when the compartment is otherwise required being empty of cargo.


Revision 1 removes Global Change and clarifies relief for cargo holds with individual smoke detection zones.

As a condition of deferral for many existing MMEL items such as air conditioning and air distribution components, smoke/fire detection systems, and other such related items, etc., cargo compartments are required to remain empty of cargo.  In an effort to address the needs of air carriers to be able to redistribute cargo handling equipment such as containers, pallets, igloos (typically referred to as Unit Loading Devices (ULDs)), ballast, and related cargo restraint components throughout their route structure, successive MMEL revisions have added statements that have attempted to address this need.  Principally, the statements; ".affected compartment remain empty, or only non- combustible (and/or non-flammable) materials are carried in the affected compartments," were added to many MMELs.  Due to the lack of availability and uniformity of definitions for such terms as combustible and flammable, many operators were confronted with the necessity to conform to only the strictest interpretation of these provisos and fly with the cargo compartment completely empty.

Most recent attempts to address this issue have resulted in MMEL provisos that have been changed to state that "...affected compartment remain empty," along with the addition of a NOTE that states "does not preclude the carriage of empty cargo containers, pallets, ballast, and cargo restraint components."  Several air carriers have expressed concern that this new standard also will not allow them to carry empty cargo handling materials because Notes, by their definition, "... do not relieve the operator of the responsibility for compliance with all applicable requirements.  Notes are not a part of the provisos."

Operators argue that this definition can lead them back to the need to void the entire compartment and once again leave urgently needed ULDs and ballast, etc., at remote locations, disrupting their system, all because the proviso they are left to comply with is essentially " Affected compartment remains empty."  Other parties have also expressed concern that this note in MMELs lacks any creditable authority to ensure that inappropriate items associated with cargo handling such as shoring timbers, plywood panels, cardboard boxes, etc., are not also being loaded.

In response to these concerns industry submits that their cargo handling materials, consisting of ULDs (containers, pallets, and igloos), ballast, and related cargo restraint components and equipment, are designed and tested to standards that are equivalent to standards that the aircraft structure must meet, principally, Title 14 Code of Federal Regulations Part 25, Appendix F, Part 1.  These items of equipment are all manufactured in accordance with various STCs, TSO, ISO, or SAE standards for such equipment.  All such standards require the equipment and its materials to meet the minimum performance standards of NAS 3610, or other designations that are in accordance with IATAs ULD Technical Manual, Chapter 5, Standards Specifications 50/0 and 50/4. These standards have been reviewed and approved, or accepted, by the Administrator for routine use in cargo carriage.

Additionally, some operators have an installed storage unit(s) called Fly Away Kits (alternately referred to as Parts for Maintenance [PFM] (Boxes), which have been reviewed and approved by the Administrator to remain on the aircraft when the compartment is to be considered empty.  The purpose of such kits is to carry aircraft certified spare parts and hardware.  It is the responsibility of each operator, who uses such kits, to ensure that they be voided of any item(s) that may not be compatible with the goal of minimizing potential sources of smoke, fume, or fire while MEL items affected by this policy are being carried on deferral.  Examples of such item(s) that must be removed are all self contained fluids, i.e., cans of hydraulic oil, cleaning solvents, etc.  In addition, any item that either stores or can produce a source of  ignition, i.e., devices that store energy such as batteries and capacitors, chemical generators, etc., must be removed. When part of a Fly Away Kit, serviceable tires should only be inflated to a minimal pressure that preserves their serviceability.

The presence of cargo handling equipment (unloaded, empty, or with ballast) or installed Fly Away Kits, onboard the aircraft constitute no greater hazard in regards to propagation of fire, smoke, and fumes than the aircraft itself.

Each operator is required to maintain records of the types of cargo handling materials they carry, and be able to demonstrate that empty cargo handling material loaded in conjunction with any MMEL proviso that mandates no cargo be carried are of these approved, or accepted, categories.  Each operator has the responsibility of ensuring and recording the exact position, and tare weight, of empty cargo equipment that are loaded onboard an aircraft in accordance with an approved weight and balance program, load manifest, etc.  Since this information must be validated by the crew, the operator wi;ll establish and use a procedure that verifies the cargo compartment is empty or contains only empty cargo handling equipment, ballast, and/or Fly Away Kits.  To maintain operational flexibility, ballast may be loaded in ULDs.



MMEL items for cargo compartment smoke detection and fire suppression systems that have provisos that state the "affected cargo compartment or zone remains empty" may be changed to read as follows:

(O)May be inoperative provided procedures are established and used to ensure the associated compartment or zone remains empty, or is verified to contain only empty cargo handling equipment, ballast (ballast may be loaded in ULDs), and /or Fly Away Kits.

NOTE:  Operator MELs should define which items are approved for inclusion in the Fly Away Kits, and which materials can be used as ballast.

Each Flight Operations Evaluation Board (FOEB) Chairman should apply this Policy to affected MMELs through the normal FOEB process.







John S. Duncan

Manager, Air Transportation Division