11.2.6 An operator may seek advice from aircraft manufacturers regarding areas of the aircraft that might have additional capability beyond the nominal capability provided by a compartment that meets the minimum standards for its classification.
11.2.7 Where an aircraft has more than one class of cargo compartment, an operator may elect to place only certain types of cargo in a particular class of compartment. For example, loading flammable items in a Class C compartment with active fire suppression versus loading in a Class E compartment that uses passive fire suppression (oxygen starvation) might mitigate the risk should a fire occur.
11.2.8 Common items, such as PEDs or batteries, carried by passengers and crew may introduce risk. Operators should address damaged items carried onboard the aircraft or damaged during flight.
11.3 Fire Containment Controls. In the event an operator cannot attain an acceptable level of risk, the operator should employ additional controls to mitigate risk, such as:
11.3.1 Packaging can prevent an event occurring at the package level from becoming an aircraft level event. An operator may require that certain hazardous materials be shipped in packaging that would prevent a failure inside the package from becoming an uncontrollable event by ensuring the effects of the failure are not spread outside the package. For example, reducing the state of charge of a shipment of batteries or requiring a specific type of packaging may allow the package to contain a failure of a battery. The benefit of this approach is that the effects of the event being mitigated are less at the package level than what can occur at the aircraft level.
11.3.2 Fire Resistant Containers (FRC) can provide passive means to contain Class A9 fires.
Technical Standard Order (TSO)-C90e, Unit Load Devices, provides performance and testing requirements for the design and production approval of an FRC. An operator may choose to utilize such ULDs in order to mitigate not only Class A fires, but also small hazardous material fires. If an operator decides to employ FRCs to mitigate hazardous material fires, refer to research at https://www.fire.tc.faa.gov/cargosafety to learn more about how various FRCs have performed during research tests. An operator may elect to utilize FRCs for:
1. All of their containerized cargo operations,
2. Specific items, or
3. Specific flight operations.
Note: TSO-C90 does not address smoke detection within the aircraft as a result of a fire starting under the fire containment cover.
11.3.3 Fire Containment Covers (FCC) can be used over non-containerized, palletized cargo to provide enhanced fire safety similar to an FRC and for similar fires (Class A plus small hazardous materials fires). Refer to TSO-C203 and https://www.fire.tc.faa.gov/cargosafety 9 Refer to AC 20-42, Hand Fire Extinguishers for Use in Aircraft, for description of fire classifications.
for information on the required performance of these covers and additional research to supplement the information in the TSO. An operator may elect to utilize FCCs for:
1. All palletized cargo operations,
2. Specific items, or
3. Specific flight operations.
Note: TSO-C203 does not address smoke detection within the aircraft as a result of a fire starting under the fire containment cover.
11.3.4 An operator may implement a fire suppression system where none is required, such as in a Class E cargo compartment or within a ULD. An operator might modify an existing suppression system to be more effective by increasing the amount of suppression agent to increase the available concentration, thereby increasing the number of hazardous materials against which the agent is effective. For example, Halon 1301 at a 3 percent concentration (typically considered effective for fire suppression) is not effective against a specific hydrocarbon gas ignition, for which a concentration around 10 percent is effective. These types of modifications may require a change to the type design and issuance of an STC.
11.3.5 The route of flight can be a mitigation by choosing to operate so that the time to diversion airports is reduced, allowing a shorter time to initiate a landing in an emergency. Selection of a route of flight that avoids highly populated areas is a potential mitigation when transporting certain specified articles and substances.
11.3.6 In the event that the other controls and mitigations listed above have not been effective, the crew may experience smoke in the flight deck that reduces visibility below that which is necessary to see either the primary flight instruments or out of the windshield.
Protective breathing equipment is already required,10 but might not provide visibility when smoke is dense and continuous. There are means to physically displace smoke in order to make the flight critical instruments and electronic systems visible in the event of significant loss of visibility in the flight deck. Some devices may also provide a clearer view out of the windshield. A manufacturer should align any vision augmentation system with the capability and duration of the protective breathing system.
11.3.7 The operator should ensure the amount of breathable oxygen onboard is sufficient to allow the flightcrew to land the aircraft in the event of an in-flight fire.
12 REQUEST FOR INFORMATION.
• The current edition of the CFRs is available at https://www.ecfr.gov.
10 Refer to Part 25, § 25.1439, Protective Breathing Equipment; 14 CFR Part 91, § 91.211, Supplemental Oxygen;
14 CFR Part 121, § 121.337, Protective Breathing Equipment; and 14 CFR Part 135, § 135.89, Pilot Requirements:
Use of Oxygen.
• Current editions of ACs are available on the FAA website at https://www.faa.gov/regulations_policies/advisory_circulars/ and on the Regulatory and Guidance Library (RGL) at https://rgl.faa.gov.
13 AC FEEDBACK FORM. For your convenience, the AC Feedback Form is the last page of this AC. Note any deficiencies found, clarifications needed, or suggested improvements regarding the contents of this AC on the Feedback Form.
ORIGINAL SIGNED by /s/ Robert C. Carty Deputy Executive Director, Flight Standards Service 13
Appendix A APPENDIX A. RELATED REGULATIONS AND STANDARDS A.1 Title 14 of the Code of Federal Regulations (14 CFR).
A.1.1 Part 5, Safety Management Systems.
A.1.2 Part 23, Airworthiness Standards: Normal Category Airplanes. Section 23.2325, Fire Protection.
A.1.3 Part 25, Airworthiness Standards: Transport Category Airplanes.
• Section 25.851, Fire Extinguishers.
• Section 25.853, Compartment Interiors.
• Section 25.855, Cargo or Baggage Compartments.
• Section 25.857, Cargo Compartment Classification.
• Section 25.858, Cargo or Baggage Compartment Smoke or Fire Detection Systems.
• Section 25.1439, Protective Breathing Equipment.
A.1.4 Part 27, Airworthiness Standards: Normal Category Rotorcraft.
• Section 27.853, Compartment Interiors.
• Section 27.855, Cargo and Baggage Compartments.
A.1.5 Part 29, Airworthiness Standards: Transport Category Rotorcraft.
• Section 29.853, Compartment Interiors.
• Section 29.855, Cargo and Baggage Compartments.
A.1.6 Part 91, General Operating and Flight Rules.
• Section 91.211, Supplemental Oxygen.
• Section 91.525, Carriage of Cargo.
A.1.7 Part 121, Operating Requirements: Domestic, Flag, and Supplemental Operations.
• Section 121.285, Carriage of Cargo in Passenger Compartments.
• Section 121.287, Carriage of Cargo in Cargo Compartments.
• Section 121.306, Portable Electronic Devices.
• Section 121.337, Protective Breathing Equipment.
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Appendix A
• Section 121.367, Maintenance, Preventive Maintenance, and Alterations Programs.
• Section 121.589, Carry-on Baggage.
A.1.8 Part 125, Certification and Operations: Airplanes Having a Seating Capacity of 20 or More Passengers or a Maximum Payload Capacity of 6,000 Pounds or More; and Rules Governing Persons on Board Such Aircraft.
• Section 125.183, Carriage of Cargo in Passenger Compartments.
• Section 125.185, Carriage of Cargo in Cargo Compartments.
• Section 125.204, Portable Electronic Devices.
A.1.9 Part 135, Operating Requirements: Commuter and On Demand Operations and Rules Governing Persons On Board Such Aircraft.
• Section 135.87, Carriage of Cargo Including Carry-on Baggage.
• Section 135.89, Pilot Requirements: Use of Oxygen.
• Section 135.144, Portable Electronic Devices.
A.2 Title 49 of the Code of Federal Regulations (49 CFR), Transportation. Refer to Subtitle B, Other Regulations Relating to Transportation, Chapter I, Pipeline and Hazardous Materials Safety Administration, Department of Transportation, Subchapter C, Hazardous Materials Regulations, as applicable.
A.3 International Civil Aviation Organization (ICAO).
• Annex 6 , Operation of Aircraft.
• Annex 18, The Safe Transport of Dangerous Goods by Air.
• Annex 19, Safety Management.
• Doc 9284, Technical Instructions for the Safe Transport of Dangerous Goods by Air.
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Appendix B APPENDIX B. REFERENCE MATERIAL B.1 Advisory Circulars (AC) (current editions).
• AC 20-164, Designing and Demonstrating Aircraft Tolerance to Portable Electronic Devices.
• AC 20-190, Aircraft Electromagnetic Compatibility Certification.
• AC 25.795-5, Cargo Compartment Fire Suppression.
• AC 25-18, Transport Category Airplanes Modified for Cargo Service.
• AC 25.857-1, Class B and F Cargo Compartments.
• AC 43-4, Corrosion Control for Aircraft.
• AC 60-22, Aeronautical Decision Making.
• AC 91.21-1, Use of Portable Electronic Devices Aboard Aircraft.
• AC 120-80, In-Flight Fires.
• AC 120-85, Air Cargo Operations.
• AC 120-92, Safety Management Systems for Aviation Service Providers.
B.2 Orders (current editions).
• Order 8000.369, Safety Management System.
• Order 8040.4, Safety Risk Management Policy.
• Order VS 8000.370, Aviation Safety (AVS) Safety Policy.
• Order VS 8000.367, Aviation Safety (AVS) Safety Management System Requirements.
B.3 Technical Standard Orders (TSO).
• TSO-C90e, Unit Load Devices.
• TSO-C203, Fire Containment Covers (FCC).
B.4 Commercial Aviation Safety Team (CAST) Safety Enhancements (SE). These SEs can be found in the CAST Safety Portfolio at https://www.cast-safety.org.
• SE027, Risk Assessments and Management.
• SE028, Process to Inform Personnel and Flight Crew.
• SE125, Cargo Hazardous Materials (HazMat) Processing.
• SE127, Cargo—Fire Containment.
• SE131, Safety Culture.
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Appendix B
• SE223, Cargo—Hazardous Material Fires—Prevention and Mitigation.
• SE224, Cargo—Hazardous Material Fires—Enhanced Fire Detection Systems (R-D).
• SE225, Cargo—Hazardous Material Fires—Containment and Suppression (R-D).
• SE226, Cargo—Hazardous Material Fires—Enhanced Protection of Occupants and Aircraft.
B.5 International Civil Aviation Organization (ICAO).
• Doc 9859, Safety Management Manual (SMM).
• Doc 10102, Guidance for the Safety Operations Involving Aeroplane Cargo Compartments.
• Doc 9734, Safety Oversight Manual.
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Appendix C APPENDIX C. RELATED REGULATIONS Note: The following table provides a summary of characteristics of cargo compartments codified at 14 CFR §§ 25.851, 25.855, 25.857, and 25.858. For operators of parts 23, 27, and 29 aircraft using this guidance to understand the aircraft capabilities and the aircraft interface with the cargo items, determine the characteristics of your cargo compartments that most closely align with the classes below.
Table C-1. Summary of Characteristics of Cargo Compartments Class A Class B Class C Class D11 Class E Class F Fire Detection Detection via crew Automatic smoke detection Automatic smoke detection No detection Automatic smoke detection Automatic smoke detection Principal Crew Action Hand-held fire extinguishing Hand-held fire extinguishing Activate fire suppression system No action unless indication of fire is present—then land as soon as possible Depressurize and set generally at FL 200/250 Depends on design Aircraft Firefighting Means Active firefighting via hand-held extinguisher Active firefighting via hand-held extinguisher Built-in fire suppression system Isolation Flight level procedure, reducing oxygen partial pressure Depends on design Firefighting Principle Extinguishing Extinguishing Fire suppression via inhibition (Halon 1301) Fire containment and oxygen consumption Oxygen starvation Depends on design Expected Post-Fire Suppression Conditions or Actions Monitoring Monitoring Until end of flight Increase of oxygen partial pressure during descent phase Increase of oxygen partial pressure during descent phase Depends on design Design Steady-State Conditions (Objective) Extinguished Extinguished Suppressed fire with cargo compartment temperature potentially >200°C Smoldering fire, depending on oxygen concentration left Similar condition as Class C cargo Depends on design 11 Due to several uncontrollable fires in Class D compartments, they were eliminated by Amendment 25-93, effective March 19, 1998. Refer to 63 Federal Register (FR) 8032 (Feb. 17, 1998). As explained in Amendment 25- 93, Class D cargo compartment standards pre-dating Amendment 25-93 are inadequate. Therefore, the FAA does not approve new Class D cargo compartments in airplanes with a certification basis pre- dating Amendment 25-93.
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______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ Advisory Circular Feedback Form If you find an error in this AC, have recommendations for improving it, or have suggestions for new items/subjects to be added, you may let us know by contacting the Flight Standards Directives Management Officer at 9-AWA-AFB-120-Directives@faa.gov.
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