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• Damage to wires, wire bundles, or parts;
• Melting of holes in sheet metal parts by faulted, high-current feeder cables;
• Melting and burning of titanium bleed air ducts by a chafed, high-current feeder cable;
• Electromagnetic interference (EMI) with equipment; and
• The simultaneous and unreasonable loss of both engine-driven generators in a two-engine airplane.
NOTE: The current edition of AC 25-16, Electrical Fault and Fire Prevention and Protection, contains additional information about this subject.
c. Using a Circuit Breaker as an On/Off Switch. Since circuit breakers are designed to open an electrical circuit automatically at a predetermined overload of current, they should not be used for day-to-day operational functions because they would not be performing their intended function, which is protection against overloads. You should not use circuit breakers, even those suitable for frequent operation, as a switch to turn protected items on or off. An air carrier should publish and include in its approved maintenance programs and flight operations manuals any exceptions to this procedure.
17. RECOMMENDED TRAINING.
a. Training Programs. Certificate holders’ crewmember training programs should stress the importance of crewmembers taking immediate and aggressive action when confronted with smoke, fumes, and in-flight fires. It should also emphasize accessing and fighting hidden fires.
b. Training. Operators should include the following knowledge and skill objectives in their crewmember training programs:
(1) Knowledge-based Objectives.
(a) In the event of a known or suspected in-flight fire, crewmembers must know how to take immediate and aggressive action to locate the source of fires.
(b) To assist crewmembers in locating the source of fires, they must know the various aircraft cabin configurations (e.g., overhead, sidewall, cheek, and tunnel areas) that they are required to operate.
(c) Crewmembers must understand the proper methods and/or techniques to gain access to areas that may support hidden fires and the location of any cabin panels that are removable without special tools.
(d) Each flightcrew member must understand the aircraft ventilation systems, including normal and abnormal procedures, with emphasis on the potential effects of airflow on hidden fires.
(e) To assist flightcrew members in maintaining internal cockpit communications when they don oxygen masks, they must know the aircraft-specific methods for establishing communication.
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(f) Each flightcrew member must know the importance of stowing their oxygen masks set to 100 percent.
(g) To enable crewmembers to locate critical equipment components within the fuselage area, operators’ manuals should contain a cross-section of the aircraft’s fuselage showing the location of electrical, fuel, and hydraulic lines.
(h) Potential indications of hidden fires and the importance of not arbitrarily resetting circuit breakers.
(2) Skill-Based Objectives.
(a) Flightcrew members should practice the procedures and/or techniques associated with:
• Planning for an immediate descent and landing at the nearest suitable airport;
• Aggressively locating the source of smoke, fumes, and fire;
• Notifying the cabin crew under non-normal circumstances;
• Operating the aircraft with the use of protective breathing equipment and smoke goggles;
• Implementing smoke and fume elimination procedures;
• Alternate means of dispersing smoke and fumes when the source of a fire is unknown; and
• Use of oxygen mask/goggle sets including the use of regulator’s emergency selector and the venting of smoke goggles.
(b) Cabin crewmembers should practice the procedures and/or techniques associated with:
• Aggressively locating the source of the fire,
• Selecting the appropriate extinguishing agent,
• Relocating passengers as necessary,
• Opening storage compartments or doors,
• Consider location of portable oxygen bottles and consider relocating portable oxygen bottles away from source of fire,
• Notifying the flight crew under non-normal circumstances, and
• Locating hot spots on interior panels.
(c) Skill-based training should be conducted jointly (pilots with F/As) to emphasize crew resource management. Crewmember performance should be evaluated in the following areas:
• Clear concise communication
• Effective decision making
• Critical CRM skills including situational awareness
• Time management
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18. OBTAINING FAA PUBLICATIONS.
a. You can find this AC on the FAA’s Web site at http://www.faa.gov/regulations_policies/advisory_circulars/.
b. FAA Handbooks and Orders are available online at http://fsims.faa.gov
c. The Code of Federal Regulations is available online at http://www.gpo.gov/fdsys/.
19. NOTES ON APPENDICES. The following appendices contain information about the dangers associated with in-flight fires. Operators may also use this information to develop training programs in support of the recommendations contained in this AC. The information does not represent a rigid FAA view of best practices, which may vary among fleets and among certificate holders, and may change over time. Some of the examples may be readily adapted to a certificate holder’s training and operating manuals for various airplane fleets. Others may apply to a certain airplane fleet and may not be adaptable apart from that fleet.
ORIGINAL signed by John S. Duncan Director, Flight Standards Service
Appendix 1 Page 1 (and 2) APPENDIX 1. NTSB ACCIDENT REVIEWS This advisory circular (AC) was originally issued in part based on the National Transportation Safety Board’s (NTSB) review of commercial aviation accidents involving in-flight fires. The scope of the review was limited to transport category airplanes operated by U.S. and foreign air carriers during the period 1983 to 2000. What follows is a brief synopsis of the events the NTSB reviewed, as well as more recent in-flight fire events.
• On June 2, 1983, a McDonnell Douglas DC-9 operated by Air Canada as flight 797 experienced an in-flight fire and made an emergency landing at Cincinnati and Northern Kentucky International Airport, Covington, KY. A passenger noticing a strange smell and a flight attendant (F/A) seeing smoke in one of the lavatories initially detected the fire. Another F/A saw that the smoke was coming from the seams between the walls and ceiling in the lavatory. During the descent, the smoke increased and moved forward in the cabin. After the airplane landed, F/As initiated an emergency evacuation. Of the 41 passengers and 5 crewmembers on board, 23 passengers were unable to evacuate and died in the fire. The airplane was destroyed.
• On September 17, 1999, a McDonnell Douglas MD-88 operated by Delta Air Lines experienced an in-flight fire and made an emergency landing at Cincinnati and Northern Kentucky International Airport, Covington, KY. The airplane sustained minor damage. There were no injuries to the 2 flightcrew members, 3 flight attendants (F/A), 3 off-duty F/As, and 113 passengers during the evacuation.
• On August 8, 2000, a McDonnell Douglas DC-9-32 operated by Air Tran Airways as flight 913 experienced an in-flight fire and made an emergency landing at Greensboro Piedmont-Triad International Airport, Greensboro, NC. The effects of fire, heat, and smoke substantially damaged the airplane. Of the 57 passengers and 5 crewmembers on board, 3 crewmembers and 2 passengers received minor injuries from smoke inhalation, and 8 other passengers received minor injuries during the evacuation.
• On November 29, 2000, lightning struck a McDonnell Douglas DC-9-82 operated by American Airlines as flight 1683, which experienced an in-flight fire that began shortly after takeoff from Reagan National Airport, Washington, DC. The flightcrew made an emergency landing at Dulles International Airport and ordered an evacuation. The airplane sustained minor damage. There were no injuries to the 2 pilots, 3 F/As, and 61 passengers during the evacuation.
Appendix 2 Page 1 (and 2) APPENDIX 2. TYPICAL WIDEBODY CROSS-SECTION Although the following diagram represents a typical widebody aircraft, many narrowbody aircraft have the same general layout and ventilation airflow. Other than the cabin height and width, the main difference between widebody and narrowbody aircraft is the volume of free space in the overhead area. This free space can range from a few feet to more than four feet in wide body aircraft and to a little as a few inches in small regional jets. Crewmembers must understand the volume of overhead space in a particular aircraft to effectively combat hidden fires in this area.
Appendix 3 Page 1 (and 2) APPENDIX 3. TIME TO BECOMING NONSURVIVABLE1 The following chart depicts the time that various crews had from the first indication of the presence of a hidden fire to the time that fire became catastrophically uncontrollable.
DATE LOCATION AIRCRAFT TYPE
TIME TO BECOME
NON-SURVIVABLE (MINUTES) 07-26-1969 BISKRA, ALGERIA CARAVELLE 26 07-11-1973 PARIS, FRANCE B-707 7 11-03-1973 BOSTON, USA B-707 35 11-26-1979 JEDDAH, SAUDI ARABIA B-707 17 06-02-1983 CINCINNATI, USA DC-9 19 11-28-1987 MAURITIUS, INDIAN OCEAN B-747 19 09-02-1998 NOVA SCOTIA, CANADA MD-11 16 For aircraft with hidden fires, an approximate assessment is that only one third will reach an airfield before the fire becomes uncontrollable.2
1 CAA PAPER 2002/02, (FAA Reference DOT/FAA/AR-02/50), “A Benefit Analysis for Enhanced Protection from Fires in Hidden Areas on Transport Aircraft, p.” 6 2 CAA PAPER 2002/02, (FAA Reference DOT/FAA/AR-02/50), “A Benefit Analysis for Enhanced Protection from Fires in Hidden Areas on Transport Aircraft,” p. 20
Appendix 4 APPENDIX 4. INFORMATION ON USING HAND FIRE EXTINGUISHERS The following information has been extracted from AC 20-42, Hand Fire Extinguishers for Use in Aircraft (current edition), and presented here for your review and ease of reference. The information presented below is current as of the date of this AC. However, this Appendix will not necessarily be updated. To ensure you have current information relating to hand fire extinguishers for use in the aircraft you should refer to the current edition of AC 20-42.
1. Types of Fires. To select an appropriate extinguisher for use in an aircraft, consider the following classes of fires (as defined in the National Fire Protection Association (NFPA) Standard 10) that are likely to occur:
a. Class A. Fires in ordinary combustible materials, such as wood, cloth, paper, rubber, and plastics, for which the quenching and cooling effects of quantities of water, or aqueous-based extinguishing agents containing a large percentage of water, are of prime importance.
b. Class B. Fires in flammable liquids, oils, greases, tars, oil-based paints, lacquers, and flammable gases, for which extinguishing agents having a blanket effect are essential.
c. Class C. Fires involving energized electrical equipment and where the electrical nonconductivity of the extinguishing agent is important.
d. Class D. Fires involving combustible metals such as magnesium, titanium, zirconium, sodium, lithium, and potassium, which require extinguishing agents of the dry powder types.
You should follow the recommendations of the manufacturer for use of those extinguishers to avoid possible chemical reaction between the burning metal and the extinguishing agent.
2. Extinguishing Agents Appropriate for Types of Fires. The following extinguishing agents are recommended, as appropriate, for use on the types of fires specified below and as defined in Chapter 3 of the current edition of AC 20-42.
a. Carbon dioxide - Class B or C.
b. Water/aqueous based extinguishing agent - Class A.
c. Dry chemicals - Class A, B, or C.
d. Halogenated hydrocarbons (halon) - Class A, B, or C.
e. Specialized dry powder - Class D.
NOTE: Only “all purpose” or A, B, C dry chemical powder extinguishers containing monoammonium phosphate have a UL Class A, B, C rating; all other powders have a Class B, C rating only.
3. Numeral Ratings. Extinguishers labeled for Class A and Class B fires use numerals with the identifying letters. The numeral indicates the relative extinguishing effectiveness of the device on a given size fire, which is dependent on the agent, the capacity of the device, discharge times,
Appendix 4 and design features. For example, an extinguisher rated as 4A should extinguish about twice as much Class A fire as a 2A rated extinguisher. A 2½-gallon water extinguisher is rated 2A. On an extinguisher rated for Class B fires, the numeral rating precedes the letter "B." Extinguishers labeled for Class C or D fires do not use numeral ratings. Extinguishers that are effective on more than one class of fires have multiple numeral-letter and letter classifications and ratings: for example, 5B:C.
4. Helpful Hints in Extinguishing Fires.
a. Generally, you can obtain the best results in firefighting by attacking the base of the fire at the near edge of the fire and progressing toward the back of the fire by moving the fire extinguisher nozzle rapidly with a side-to-side, sweeping motion.
b. The effective discharge time of most hand-held fire extinguishers ranges from 8 to 25 seconds depending on the capacity and type of the extinguisher. Because of this relatively short effective time span, the crewmember must select and use the proper fire extinguisher without delay.
c. Care must be taken not to direct the initial discharge at the burning surface at close range (less than 5 to 8 feet) because the high-velocity stream may cause splashing and/or scattering of the burning material.
d. Ventilate the compartment promptly after successfully extinguishing the fire to reduce the gaseous combustion and gases produced by thermal decomposition.