U.S. Department 

of Transportation 

Federal Aviation 

Administration

Advisory 

Circular 

Subject: IN-FLIGHT FIRES Date: 1/8/04

Initiated by: AFS-210 

AC No: 120-80 

1. WHAT IS THE PURPOSE OF THIS ADVISORY CIRCULAR (AC)? 

a. General. The National Transportation Safety Board (NTSB) conducted a 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. That review prompted the NTSB to issue a number of safety recommendations to the 

FAA, including A-01-83 through A-01-87 (see Appendix 1). The NTSB recommended that an 

Advisory Circular (AC) be developed and issued by the FAA to address a number of issues 

linked to in-flight fires. The FAA agrees with the safety intent of those recommendations and 

has developed the guidance material that follows. Specifically, this AC: 

• Discusses the dangers of in-flight fires, with particular emphasis on hidden fires that 

may not be visible or easily accessed by the crew. It discusses the importance of 

recognizing and quickly assessing the conditions that may be associated with hidden 

fires and the importance of taking immediate action to gain access to fires that are 

located behind interior panels. 

• Provides guidance on how to deal with in-flight fires, emphasizing the importance of 

crewmembers taking immediate and aggressive action in response to signs of an inflight fire while stressing the effectiveness of Halon extinguishing agents. 

• Discusses the importance of appropriate crewmember training in dealing with hidden 

fires, the effective application of fire extinguishing agents behind interior panels, and 

the urgency of the crew’s action in dealing with such fires. 

• Complements guidance previously developed for crewmembers concerning the 

proper use of cabin fire extinguishers (AC 20-42C, Hand Fire Extinguishers for Use 

in Aircraft, and National Fire Protection Association (NFPA) 408, Standard for 

Aircraft Hand Portable Fire Extinguishers) and the most effective means of 

extinguishing fires that are readily accessible. 

• Includes information from research conducted by the FAA’s Technical Center. As 

additional information becomes available, it will be published in future revisions to 

this AC. 
AC 120-80 1/8/04 

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b. Who should read this AC? Crewmembers operating transport category airplanes under 

14 CFR part 121; also, crewmembers of passenger-carrying airplanes operating under other 

parts, including parts 125, 135, and 91. In particular, directors of safety, directors of operations, 

chief pilots, and training managers should read this AC. 

c. Using this AC. When tailored to a specific aircraft and operators’ procedures, the 

suggested guidelines presented in this AC provide a good framework for defense against in-flight 

fires. However, approved manufacturer’s procedures and company procedures take precedence 

over the information presented in this AC. The importance of crewmembers taking immediate 

and aggressive action to locate the source, gain access, and effectively apply extinguishing 

agents to hidden fires cannot be overstressed. This task is complicated by the multitude of cabin 

configurations that are currently in use throughout the industry. For this reason there is no single 

formula for fighting/extinguishing in-flight fires. 

2. DEFINITIONS. 

a. Aggressively Pursue. Aggressively pursuing a fire means taking immediate action to 

determine the source of hot spots, smoke and/or flames. The crew should quickly evaluate the 

situation; gain access to the fire and attack the fire using all available resources, which may 

include deadheading crewmembers or able-bodied passengers (ABP). 

b. Cheek Area. This term describes the area just below the floor, outboard of the cargo 

compartment areas. In narrow and widebody aircraft this area houses wire bundles, hydraulic 

lines, and other electrical components. (See Appendix 2.) 

c. Circuit Breaker. CBs are designed to open an electrical circuit automatically at a 

predetermined overload of current. 

d. Halon. Halon is a liquefied gas that extinguishes fires by chemically interrupting a fire’s 

combustion chain reaction, rather than physically smothering it. This characteristic is one of the 

main reasons that Halon extinguishers are effective when the exact source of the fire cannot be 

positively determined. Halon fire extinguishing agents that have been approved for use in 

aircraft include Halon 1211, Halon 1301, and a combination of the two (Halon 1211/1301) Both 

are typified as “clean agents,” leaving no agent residue after discharge. 

(1) Halon 1211. The chemical name is bromochlorodifluoromethane. Halon 1211 is a 

multipurpose, Class A, B, and C rated agent that is effective against fires fueled by flammable 

liquids. Halon 1211 fire extinguishers discharge in an 85 percent liquid stream, giving the agent 

a range of 9-to-15 feet, which offers a significant advantage in fighting fires in large aircraft 

cabins. 

(2) Halon 1301. The chemical name is bromotrifluomethane. Halon 1301 has Class A, 

B, and C capability in total flooding systems; however, Halon 1301 has limited Class A 

capability when used in portable fire extinguishers. The useable range of a Halon 1301 

extinguisher is slightly less than that of a 1201 extinguisher. 
1/8/04 AC 120-80 

Par 2 Page 3 

e. Hidden Fires. Fires that are “hidden” are not readily accessible, may be difficult to locate 

and are more challenging to extinguish. Some examples of hidden fires would be fires behind 

sidewall paneling or in overhead areas. 

f. Overhead Area. Area within the aircraft fuselage located above the ceiling panels. This 

area ranges in volume, depending on the aircraft type. In a narrowbody transport, this area may 

be only several inches high running the length of the fuselage. In widebody aircraft, however, 

this volume is much larger, and may range in height from 2 to 4 feet or more. A typical 

overhead area contains components of the aircraft’s entertainment system, numerous wiring 

bundles, control surface cables, portions of the air conditioning system, passenger emergency 

oxygen system and other systems. (See Appendix 2.) 

g. Return Air Grills. These are vents located along the baseboard area of each sidewall of 

the passenger cabin. Most transport category aircraft have air conditioning systems that supply 

conditioned air near the cabin ceiling. This air flows in a top-to-bottom direction, exiting 

through the return grills, and eventually out the fuselage via the outflow valve(s). 

h. Recirculation Fan. These units are typically located in the overhead area, and are used 

to recirculate air in this space, to prevent elevated temperatures, and to remove stagnant air. 

i. Smoldering Fire. A smoldering fire is characterized by combustion without a visible 

flame and a slow combustion rate. A smoldering fire left unattended or a fire that has not been 

completely extinguished can ignite and grow into a larger uncontrollable fire in a short time. 

j. Suppressed Fire. A fire that has been partially extinguished which may or may not have 

visible flames. A suppressed fire if not extinguished, may re-establish itself and grow into a 

larger, uncontrollable fire in a short period of time. 

3. WHAT ARE SOME OF THE MORE SUBTLE CAUSES OF IN-FLIGHT FIRES?

a. Wiring Failures. A majority of hidden in-flight fires are the result of electrical arcs 

along wire bundles. In most cases, the electrical arc acts as the initiating event, igniting other 

surrounding materials. The surface of insulation materials is often a conveyer of these initiating 

events, as contamination from spillage, accumulated dirt/dust, lubrication or corrosion inhibitors 

on these surfaces can promote flame spread (uncontaminated insulation materials are generally 

very fire resistant). In other instances, the re-setting of a tripped circuit breaker can overheat 

wiring, ultimately leading to failure and arcing, causing the same chain of events. 

b. Electrical Component Failures. Electrical motors can overheat, bind, and fail, and 

possibly ignite surrounding materials. The spread of fire in these instances is exacerbated by an 

accumulation of contaminants in the immediate area. 

c. Lightning Strikes. Although very infrequent, there have been instances in which a 

lightning strike has initiated a fire. In these instances faulty or contaminated insulation material 

contributed to the fire. 
AC 120-80 1/8/04 

Page 4 Par 3 

d. Bleed Air Leaks. Aircraft with systems that use air from the engine (bleed air) depend 

on a series of pneumatic lines to deliver the air supply. A failure of any of these supply lines, if 

left unchecked, can cause high temperatures in the surrounding area and damage to the aircraft’s 

equipment, wiring, and associated components. High temperature bleed air leaks have been 

known to cause in-flight fires and structural damage. 

e. Faulty Circuit Protection. A malfunctioning CB that does not open (trip) when an 

abnormally high current draw is detected may cause the affected unit or associated wiring to 

overheat and ignite. 

4. WHAT ARE SOME OF THE INDICATIONS OF HIDDEN FIRES? 

a. Abnormal Operation or Disassociated Component Failures. Failure or uncommanded operation of an aircraft component may indicate a developing fire. Electrical 

connections and the components themselves may have been damaged by a fire in the area of the 

component or at any point along its power supply line. For this reason cabin crewmembers 

should report all failures of electrical items to the flightcrew in accordance with company policy. 

b. Circuit Breakers. Circuit Breaker(s) tripping, especially multiple breakers such as 

entertainment systems, coffee makers, etc., may be an indication of damage occurring in a 

hidden area common to the affected components. 

c. Hot Spots. Hot spots on the floor, sidewall, ceiling or other panels should be 

immediately investigated. 

d. Odor. This may be one of your first indications of an impending fire. Never ignore a 

strange odor; you need to identify its source as soon as possible. 

e. Visual Sighting – Smoke. Smoke coming from vents or seams between interior panels, 

especially from the ceiling area, is a sure sign of a problem, and you should take immediate 

action to determine the source. 

5. WHAT ARE SOME OF THE RESOURCES AVAILABLE FOR FIGHTING INFLIGHT FIRES? 

a. The answer depends on the aircraft’s specific cabin configuration, which may vary within 

types. Therefore, crewmembers should include this subject in crew briefings as suggested in 

AC 120-48, Communication and Coordination Between Flight Crewmembers and Flight 

Attendants. 

b. In addition to the aircraft’s required emergency equipment, crewmembers should also 

consider those items that are not normally thought of as fire fighting aids. For example, 

non-alcoholic beverages such as coffee, soda, juice, or water may be poured onto a fire. A 

carbonated beverage may be used as a fire extinguisher by shaking up the can or bottle, opening 

the top, and spraying the contents at the base of the fire. Additionally, wet blankets or pillows 

may be used as smothering devices to help extinguish a fire and prevent re-ignition. Any of 
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these suggestions may prove to be effective as possible fire fighting methods. These examples 

are not meant to be all-inclusive, and crewmembers should consider what other items might be 

useful. 

c. Crewmembers should consider deadheading crewmembers and able-bodied 

passengers (ABP) as additional resources when combating a fire. The ability to enlist the help of 

qualified individuals, especially on a single flight attendant operation, might be very valuable in 

combating a fire and communicating with the flight deck crewmembers. Regardless of the type 

of operation, crewmembers should consider and use all available resources when faced with an 

in-flight fire. 

6. FIRE EXTINGUISHERS. 

a. Which type of fire extinguisher should I use? Immediate and aggressive action when 

confronted with a potential fire is much more important than delaying while you attempt to classify 

a particular fire. As a general rule Halon fire extinguishers are your best choice since Halon is 

classified as a multipurpose (Class A, B, & C fires) agent. Halon extinguishes fires by chemically 

interrupting a fire’s combustion chain reaction, rather than by physically smothering the fire. 

Approved Halon-type extinguishers are three times as effective as Carbon Dioxide (CO2) 

extinguishers with the same weight of extinguishing agent. 

b. When a fire is discovered, the initial focus should be on extinguishing the fire and then 

following-up with the appropriate class of fire extinguisher. Generally, you should consider 

using the first available extinguisher rather than delaying your fire fighting efforts while you 

locate the most appropriate extinguisher. After you have initially suppressed the fire or 

exhausted the first fire extinguisher, you should use the preferred extinguishing agent for the 

class of fire to maintain control or extinguish the fire. (See Appendix 4.) 

c. There are a few exceptions to this general guidance. A water fire extinguisher (H2O) 

should not be discharged directly into a CB panel or an electrical outlet. Nor should water be 

used to combat a liquid fire (e.g., grease or fuel) that is pooled or has collected on a non-porous 

surface. The use of an H2O extinguisher on a fire fueled by flammable liquids is acceptable if 

the surface has absorbed the liquid, such as gasoline poured on a seat or other absorbent material. 

d. Why is it important to keep hand-held fire extinguishers upright? Hand-held fire 

extinguishers are designed to be used in the upright position. Most extinguishers have been 

designed with a center siphon tube that extends to the bottom of the canister. Placing a fire 

extinguisher on its side or upside down prevents the agent from flowing through the tubing, 

which has been designed to collect the agent from the bottom of the canister. Laying the 

extinguisher on its side or turning it upside down to aim at the ceiling may limit the amount of 

extinguishing agent that is available to be discharged, thereby reducing the extinguisher’s fire 

fighting capacity. Consequently, fire extinguishers equipped with flexible discharge hoses and 

nozzles are better suited to handle fires that may require discharging the agent in an upward 

direction or in any other situation requiring flexibility. The installation and use of fire 

extinguishers with flexible hoses is highly desirable for these reasons. 
AC 120-80 1/8/04 

Page 6 Par 7 

7. CAN HALON CAUSE HARM TO PASSENGERS AND CREW? 

a. Generally speaking, no. Various publications, including AC 20-42C, caution against 

exposure to “high levels” of Halon in confined spaces, citing the possibility of dizziness, 

impaired coordination, and reduced mental sharpness. AC 20-42C also provides guidelines that 

describe what is meant by the term “high level” and further states that these levels should not be 

exceeded in ventilated or non-ventilated passenger compartments on aircraft. However, studies 

have shown that discharging all of the hand-held Halon extinguishers required by regulation in 

the passenger cabin of an air carrier aircraft will not exceed the maximum concentration levels of 

Halon vapor specified in AC 20-42C or by NFPA 408 guidelines. 

b. NTSB investigations of in-flight fires indicate that crewmembers have been hesitant to 

use Halon extinguishers during flight because of mistaken ideas about adverse effects of Halon. 

In one instance, a flight attendant went to the flight deck to inform the flightcrew of a fire and 

asked the captain whether to spray Halon into a vent where she suspected a fire. The captain 

instructed her not to use the Halon extinguisher, indicating he was concerned about spraying 

Halon in the cabin. In another instance, an off-duty company pilot considered using a Halon fire 

extinguisher, but decided against doing so because he was concerned that the Halon “would take 

away more oxygen.” In each instance, the crewmembers lost critical time and delayed the 

aggressive pursuit of the fire. 

c. The NTSB has expressed concern that risks of exceeding the maximum recommended 

levels of Halon gas outlined in AC 20-42C have been overemphasized in crewmember training 

programs, especially when compared to the risks of an in-flight fire. The NTSB emphasizes 

“...that the potential harmful effects on passengers and crew [of Halon] are negligible compared 

to the safety benefits achieved by fighting in-flight fires aggressively.” The toxic effects of a 

typical aircraft seat fire, for example, far outweigh the potential toxic effects of discharging a 

Halon fire extinguisher. 

8. QUESTIONS FOR CREWMEMBERS TO CONSIDER.

a. How critical are small in-flight fires? In-flight fires left unattended, particularly those 

that are not readily accessible, may lead to catastrophic failure and have resulted in the complete 

loss of airplanes. Fire tests conducted by various regulatory authorities have shown that fires 

allowed to spread into the aircraft’s overhead area may become uncontrollable in as few as 8-10 

minutes. 

Studies have also shown that a flightcrew may have as few as 15-20 minutes to get an aircraft on 

the ground if the crew allows a hidden fire to progress without any intervention. Appendix 3 

provides various illustrations of the time from the first indication to the crew of the presence of a 

hidden fire until it becomes catastrophically uncontrollable. These studies and other experience 

indicate that flight crewmembers should begin planning for an emergency landing as soon as 

possible after the first indication of fire. Delaying the aircraft’s descent by only a couple of 

minutes might make the difference between a successful landing and evacuation and complete 

loss of an aircraft and its occupants. 
1/8/04 AC 120-80 

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b. As a crewmember, what should I do if I suspect a hidden fire? In accordance with 

company policies and procedures, coordinate with other crewmembers as applicable and take 

immediate and aggressive action to locate and extinguish the fire. 

c. Is it necessary that I locate the exact source of a fire before applying extinguishing 

agent? If possible, yes. For example, a fire located behind a panel or within a cupboard area in 

the lavatory probably would not be successfully extinguished by discharging a fire extinguisher 

into the lavatory without first opening the cupboard or gaining access to the area behind the 

panel where the fire is located. An additional example would be a fire in the overhead area 

above a ceiling. Depending on the volume of the overhead area, discharging a fire extinguisher 

randomly without attacking the base of the flames or smoldering material probably would have 

no effect on the fire. It is unlikely that a fire in this area would be extinguished unless 

extinguishing agents were applied directly to the base or source of the fire. 

d. Should I consider cutting or punching a hole in an aircraft cabin wall, ceiling, or 

floor panel in order to gain access to a fire? If this is the only way to gain access to the fire, 

yes. In this situation, the risk of damaging equipment behind the paneling and the possibility of 

creating a bigger problem must be weighed against the catastrophic potential of in-flight fires left 

unattended. 

e. What resources can I use to access hidden fires? You should consider all available 

resources to access a hidden fire. Items found in carry-on baggage might be useful nontraditional resources, such as a shoehorn, knitting or crocheting needles, walking canes, and 

fairly rigid items that could pry apart paneling. 

One of the best defenses is to be familiar with the interior configuration of the specific aircraft. 

This familiarity provides clues as to what tools would be most effective when trying to gain 

access to hidden areas of the aircraft. For example: 

• Some aircraft are equipped with a manual release tool that is designed to open the 

oxygen compartments. This device may be used to separate or pull apart sidewall 

panels to permit access to a hidden fire. 

• Some B-747-200s have cabin ceiling speaker covers that can be removed by simply 

snapping them out of their fixture. The removal of theses covers provides access to 

the overhead in the immediate area of the speaker fixture. 

• Equipment located in raft survival kits that are not an integral part of a survival raft 

may be useful for gaining access to hidden fires. 

• Galley equipment such as casserole or ice tongs, metal cutlery, or similar items may 

be useful in separating interior panels. 

One of the most important elements in successfully combating an in-flight fire is an individual’s 

own resourcefulness and determination in accessing hidden areas within the aircraft.
AC 120-80 1/8/04 

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f. What is the best way to locate hot spots on a door or interior panel before attempting 

to open or remove it? While there is no single best method, we suggest using the back of your 

hand instead of your fingers or palm. The skin on the back of your hand is more sensitive to 

temperature variations than your palm or fingertips. Using the back of your hand allows you to 

be more aware of temperature fluctuations as you run your hand along a panel making it easier to 

locate hot spots on the panel. Also, using the back of the hand protects your palm and fingers 

from being immobilized in case the object is so hot that it could burn your hand. For example, if 

you were to grasp a hot door handle (e.g., lavatory door) using the palm of your hand, there is the 

possibility of burning your hand. A burned hand would make your fire fighting activities more 

difficult and could cause a delay in extinguishing the fire and conducting an evacuation of 

passengers. 

g. As a crewmember, if I suspect a fire in a lavatory, what action should I take? 

(1) If you suspect a fire in a lavatory you should immediately notify another crewmember, 

get the closest fire extinguisher and check the door for heat. 

(2) Cautiously and slowly open the lavatory door. Try to locate the source of the fire and 

discharge the fire extinguisher at the base of the fire. If you cannot clearly identify the source of 

the fire aggressively attempt to locate the cause of the smoke and extinguish the fire. If the base 

of the flames or the source of the fire cannot be readily identified, do not discharge the agent 

with the intent of suffocating the smoke. This is not an effective way to fight a fire and would 

only waste valuable extinguishing agent when the source or base of the fire is not accessible. 

Remember, it is critically important that you protect yourself from the effects of smoke and 

fumes while attempting to fight a fire. Do not enter an enclosed area or begin to battle a fire that 

is generating heavy smoke without first donning your protective breathing equipment (PBE). A 

small fire can quickly grow to be large and uncontrollable. Time is critical when combating an 

in-flight fire and every available resource must be used to locate and extinguish it. Research has 

shown that a fire left uncontained can destroy an aircraft in as few as 20 minutes and a smoke 

filled cabin can be completely consumed by fire in as few as 6 to 10 minutes. 

9. WHEN NOTIFIED OF A CABIN FIRE WHAT ACTIONS SHOULD THE 

FLIGHTCREW TAKE? 

a. Technical evaluations and actual experience indicate that flight deck crewmembers should 

immediately follow company approved emergency procedures, notify ATC, and begin planning 

for an emergency landing as soon as possible. Delaying decent by only a couple of minutes may 

make the difference between a successful landing and evacuation and complete loss of the 

aircraft. If there is a fire in the flight deck compartment, pilots should notify the flight 

attendant(s) to prepare the cabin occupants for an emergency landing and evacuation in 

accordance with company procedures and, if appropriate, assist in fighting the fire. 

b. Flight crewmembers must don smoke goggles and oxygen masks at the first indication of 

smoke or fumes and before accomplishing any abnormal or emergency procedures associated 

with smoke or fume elimination in accordance with your company’s approved procedures and/or 
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the manufacturer’s recommendations. Any delay might result in a crewmembers’ inability to 

breathe and/or see. 

c. Smoke and fume elimination procedures are designed primarily to evacuate the cabin of 

foreign pollutants. These procedures are not designed to eliminate the cause of the pollutant but 

rather to increase the aircraft’s airflow to evacuate the pollutant. If the cause of the pollutant is a 

fire and the fire has not been extinguished, it is possible to worsen the situation by increasing 

airflow through the area where the fire or smoldering condition exists. For this reason, it is 

important to extinguish the fire first. If the original source of the fire cannot be determined, 

exercise caution when attempting to eliminate smoke and fumes from the aircraft. Your best 

defense as a flight crewmember is to have a good understanding of your aircraft’s ventilation 

and/or pressurization systems and the location of major components within the fuselage. You 

must not delay taking corrective action in accordance with company-approved procedures for 

any reason. 

d. The flightcrew’s best defense against smoke and fumes is the quick donning of oxygen 

masks and associated smoke goggles. If you are required to leave the flight deck to assist in 

fighting a cabin fire, the FAA recommends that you don a PBE before leaving the flight deck. If 

you are to assist in an evacuation, you should don a PBE if you suspect that there is smoke or 

fumes in the cabin. 

e. Recommended Procedures.

• Immediately don protective equipment 

• Plan for an immediate descent and landing at the nearest suitable airport 

• Do not use smoke/fume elimination procedures to treat a fire 

• Do not reset CBs, unless required for safe flight 

10. IF FLIGHT ATTENDANTS ARE ONBOARD, WHAT CAN THEY DO? 

a. Company procedures should specify how a fire emergency should be handled, especially 

if there are multiple flight attendants onboard. However, one method that may be beneficial is to 

consider using a team approach to combat a fire. The team approach consists of using multiple 

flight attendants to assist in combating the fire. 

The following Team example assumes a crew of five with three flight attendants and two pilots. 

Although the example assumes there are three flight attendants the team approach can be 

modified to fit any number of participants greater than one. 

The crewmember (typically a flight attendant) who finds the fire is usually the person who is the 

firefighter. The firefighter aggressively attempts to locate the source of the fire, fights the fire, 

and actively tries to extinguish the fire. A second crewmember may serve as a communicator. 

The communicator relays factual information to the flight deck including the location, source, 
AC 120-80 1/8/04 

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and severity (e.g., is the fire under control, spreading, contained, extinguished) of the fire, the 

number of fire extinguishers used, smoke conditions, and what is being done to extinguish the 

fire (prying apart paneling, discharging an extinguishing agent into the sidewall or overhead). 

The communicator also makes announcements to inform and calm the passengers. Another 

crewmember, a runner, can assist by: 

• Obtaining additional firefighting supplies 

• Relocating passengers 

• Distributing towels for passengers’ use to cover their noses or mouths to filter out smoke 

• Ensuring aircraft and or therapeutic oxygen bottles are moved out of the immediate area 

• Generally assisting with firefighting support activities as may be required 

b. In a single flight attendant operation, when a fire is suspected, immediate communication 

and coordination with the flight deck is critical. Be sure to follow established company 

procedures. The flight attendant performs a variety of tasks with the most important being 

aggressively pursuing and extinguishing the fire. 

c. Recommended Procedures. 

• Be aggressive; if flames are visible, fight the fire immediately 

• Someone must immediately notify the flightcrew 

• If flames are not visible, find the base or source of the fire 

• Do not reset CBs, unless required for safe flight 

• Relocate passengers as necessary 

• Locate hot spots using the back of your hand 

• Don PBE 

• When searching for the source of a fire, open storage compartments or doors very 

carefully 

11. WHAT IS THE FAA’S POLICY ABOUT RESETTING TRIPPED (POPPED) 

CIRCUIT BREAKERS (CB) IN-FLIGHT? 

a. Resetting Circuit Breakers In Flight. The FAA reiterates its concern about resetting 

CBs during flight. Crewmembers may create a potentially hazardous situation if they reset a CB 

without knowing what caused it to trip. A tripped CB should not be reset in flight unless doing 
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so is consistent with explicit procedures specified in the approved operating manual used by the 

flightcrew or unless, in the judgment of the captain, resetting the CB is necessary for the safe 

completion of the flight. A detailed entry in the aircraft’s maintenance log is a proven safety 

practice for tracking purposes, and may provide maintenance personnel with key information to 

enable prompt trouble-shooting and effective corrective action on the ground. 

Air Carrier manuals and training programs should contain company policies and explicit 

procedures regarding resetting tripped CBs, both during flight and on the ground. The 

procedures shown in the manuals used by the air carrier’s crewmembers, maintenance personnel 

and airplane ground servicing personnel should be consistent with the airplane manufacturer’s 

guidance. Crewmembers should be reminded that a CB should not be used as a switch to 

perform procedural functions unless doing so is specified in approved company procedures or 

manufacturer’s operating procedures. 

b. What are the potential hazards associated with tripped circuit breakers? The FAA 

has published guidance material that states that circuit breakers are slow acting devices and may 

not offer sufficient disconnect protection during events such as arc tracking or insulation 

flashover. Arc tracking is a phenomenon in which a conductive carbon path is formed across an 

insulating surface. The carbon path provides a short circuit path through which current can flow 

(e.g., electrical arcing.) The effects of electrical faults can include: 

• Component overheating 

• Toxic fumes 

• Smoke 

• Fire 

• 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 chaffed, high current feeder 

cable 

• Electromagnetic interference (EMI) with equipment 

• The simultaneous and unreasonable loss of both engine driven generators in a twoengine airplane 

Additional information may be found in AC 25-16, Electrical Fault and Fire Prevention and 

Protection. 

c. May crewmembers use a CB as an on/off switch? Since CBs are designed to open an 

electrical circuit automatically at a predetermined overload of current, they should not be used 
AC 120-80 1/8/04 

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for day-to-day operational functions because they would not be performing their intended 

function, which is protection against overloads. Circuit breakers, even those suitable for frequent 

operation, should not be used as a switch to turn protected items on or off. Exceptions to this 

procedure should be published and included in an air carrier’s approved maintenance programs 

and flight operations manuals. 

12. RECOMMENDED TRAINING. 

a. Training Programs. Certificate holders’ crewmember training programs should stress 

the importance of crewmembers taking immediate and aggressive action when confronted with 

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 supports hidden fires and the location of any cabin panels that can be 

removed without special tools. 

(d) Each fight crewmember must understand the aircraft ventilation systems, 

including normal and abnormal procedures, with emphasis on the potential effects of airflow on 

hidden fires. 

(e) 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. 

(f) Potential indications of hidden fires and the importance of not arbitrarily resetting 

CBs. 

(2) Skill-based Objectives.

(a) Cabin crewmembers should practice the procedures and/or techniques associated 

with: 

• Aggressively locating the source of the fire 
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• Selecting the appropriate extinguishing agent 

• Relocating passengers as necessary 

• Opening storage compartments or doors 

• Notifying the flightcrew under non-normal circumstances 

• Locating hot spots on interior panels 

(b) Flight crewmembers 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 a fire 

• Notifying the cabin crew under non-normal circumstances 

• Operating the aircraft with the use of protective breathing equipment and 

smoke goggles 

• Alternate means of dispersing smoke and fumes when the source of a fire is 

unknown 

13. RELATED REGULATIONS (Title 14 of the Code of Federal Regulations (14 CFR)). 

• Part 25, section 25.851 

• Part 91, section 91.513 

• Part 121, sections 121.119, 121.215, 121.221, 121.273, 121.275, 121.308, 121.309, 

121.337, 121.417, and 121.703 

• Part 135, sections 135.170, 135.331, and 135.415 

14. RELATED ADVISORY CIRCULARS. 

• AC 20-42C, Hand Fire Extinguishers for Use in Aircraft 

• AC 25-9A, Smoke Detection, Penetration, and Evacuation Tests and Related Flight 

Manual Emergency Procedures 

• AC 25-16, Electrical Fault and Fire Prevention and Protection 
AC 120-80 1/8/04 

Page 14 Par 14 

• AC 120-48, Communication and Coordination Between Flight Crewmembers and Flight 

Attendants 

15. RELATED RESEARCH MATERIAL. You can obtain the following documents from 

various public sources such as the world wide web, public and university libraries, and the 

government entities or associations who published them. 

• A Benefit Analysis for Enhanced Protection from Fires in Hidden Areas on Transport 

Aircraft, DOT/FAA/AR-02/50, CAA Paper 2002/01, Report prepared by R G W Cherry 

and Associates 

• In-Flight Aircraft Seat Fire Extinguishing Tests (Cabin Hazard Measurements), 

DOT/FAA/CT-82/111, Hill, R.G., and Speitel, L., December 1982 

• Effectiveness of Flight Attendants Attempting to Extinguish Fires in an Accessible Cargo 

Compartment, DOT/FAA/AR-TN99/29, Blake, D.R., April 1999 

• Halon Extinguishment of Small Aircraft Instrument Panel Fires, DOT/FAA/CT-86/26, 

Slusher, G.R., Wright, J.A., and Speitel, L.C., December 1986 

• NFPA 408, Standard for Aircraft Hand Portable Fire Extinguishers, 1999 Edition 

• NFPA 12B Standard on Halon 1211 Fire Extinguishing Systems, 1990 Edition 

• Halon 1211-Exposure Hazards, Ansul Technical Bulletin Number 47, 1980 

• Chapters and sections of FAA Order 8400.10, Air Transportation Operations Inspector’s 

Handbook, that address cabin safety issues and emergency procedures 

16. HOW CAN I OBTAIN FAA PUBLICATIONS? 

a. For copies of free FAA Handbooks/Orders, the AC checklist, or ACs for which there is 

not a charge, send a written request to: 

U.S. Department of Transportation, 

Subsequent Distribution Office, SVC-121.23 

Ardmore East Business Center 

3341Q 75th Avenue 

Landover, MD 20785 

FAX (301) 386-5394 (They accept mail and FAX request only.) 

You may obtain FAA Handbooks and Orders on line at:

http://www.faa.gov/avr/afs/ 
1/8/04 AC 120-80 

Par 16 Page 15 (and 16) 

You may also obtain Advisory Circulars on line at: 

http://www.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/

MainFrame?OpenFrameSet 

b. To purchase copies of Title 14 of the Code of Federal Regulations (14 CFR), FAA 

Handbooks/Orders, and ACs, send all requests to: 

Superintendent of Documents 

P.O. Box 371954 

 Pittsburgh, PA 15250-7954 

 (202) 512-1800 – Order Desk 

You may also obtain 14 CFR on line at: 

http://www.faa.gov/ or 

 http://www.access.gpo.gov/nara/cfr/cfrhtml_00/Title_14/14tab_00.html

James J. Ballough 

Director, Flight Standards Service 
1/8/04 AC 120-80 

 Page i (and ii) 

NOTES ON APPENDICES 

The following appendices contain information about the dangers associated with in-flight fires. 

This information may also be used 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. 
1/8/04 AC 120-80 

 Appendix 1 

 Page 1 (and 2) 

APPENDIX 1. NTSB ACCIDENT REVIEWS 

This AC was issued in part based on the following NTSB investigations of recent in-flight fires: 

• 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, Kentucky. The airplane 

sustained minor damage. There were no injuries to the 2 flight crewmembers, 3 flight 

attendants, 3 off-duty flight attendants, 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, North Carolina. The 

airplane was substantially damaged from the effects of fire, heat, and smoke. 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, a McDonnell Douglas DC-9-82 operated by American 

Airlines as flight 1683, was struck by lightning and 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 flight attendants, and 61 passengers during the evacuation. 

• 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, Kentucky. The fire was 

initially detected when a passenger noticed a strange smell and a flight attendant saw 

smoke in one of the lavatories. Another flight attendant 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, flight attendants 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. 
1/8/04 AC 120-80 

 Appendix 2 

 Page 1 (and 2) 

APPENDIX 2. TYPICAL WIDE BODY CROSS SECTION 

Although the following diagram represents a typical wide body aircraft, many narrow body 

aircraft have the same general layout and ventilation air flow. Other than the cabin height and 

width the main difference between wide body and narrow body aircraft is the volume of free 

space in the overhead area. This free space can range from a few feet to more than 4 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. 
1/8/04 AC 120-80 

 Appendix 3 

 Page 1 (and 2) 

APPENDIX 3. TIME TO BECOMING NONSURVIVABLE 1

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 NONSURVIVABLE 

(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, 

SAUDIA 

ARABIA 

B-707 17 

06-02-1983 CINCINATTI, 

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 
1/8/04 AC 120-80 

 Appendix 4 

 Page 1 

APPENDIX 4. INFORMATION ON USING HAND FIRE EXTINGUISHERS 

The following information has been extracted from AC 20-42C, Hand Fire Extinguishers for 

Use in Aircraft, 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 AC 20-42. 

a. 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: 

(1) 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 of solutions 

containing a large percentage of water, are of prime importance. 

(2) Class B. Fires in flammable liquids, oils, greases, tars, oil base paints, lacquers, and 

flammable gases for which extinguishing agents having a blanket effect are essential. 

(3) Class C. Fires involving energized electrical equipment and where the electrical 

nonconductivity of the extinguishing agent is important. 

(4) Class D. Fires, involving combustible metals such as magnesium, titanium, 

zirconium, sodium, lithium, and potassium, and require extinguishing agents of the dry powder 

types. The recommendations of the manufacturer for use of those extinguishers should he 

followed because of the possible chemical reaction between the burning metal and the 

extinguishing agent. 

b. 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 paragraph 7a of AC 20-42C: 

(1) Carbon Dioxide - Class B or C. 

(2) Water - Class A. 

(3) Dry Chemicals - Class A, B, or C. 

(4) Halogenated Hydrocarbons (Halon) - Class A, B, or C. 

(5) 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. 
AC 120-80 1/8/04 

Appendix 4 

Page 2 

APPENDIX 4. INFORMATION ON USING HAND FIRE EXTINGUISHERS 

(Continued) 

c. Numeral Ratings. Numerals are used with the identifying letters for extinguishers 

labeled for Class A and Class B fires. 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, 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 2 1/2-gallon 

water extinguisher is rated 2A. On an extinguisher rated for Class B fires, the numeral rating 

precedes the letter "B". Numeral ratings are not used for extinguishers labeled for Class C or D 

fires. Extinguishers that are effective on more than one class of fires have multiple 

numeral-letter and letter classifications and ratings: for example, 5B:C. 

d. Helpful Hints in Extinguishing Fires. 

(1) Best results in fire fighting are generally obtained 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. 

(2) The effective discharge time of most hand-held fire extinguishers ranges from 8-to25 seconds depending on the capacity and type of the extinguisher. Because of this relatively 

short effective time span, the proper selection and use of the fire extinguisher must be made 

without delay. 

(3) 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. 

(4) Ventilate the compartment promptly after successfully extinguishing the fire to 

reduce the gaseous combustion and gases produced by thermal decomposition.