Cabin safety incident investigations

This is a guide for cabin investigators responsible for investigating an incident and explains the investigation process.

The guide also provides material to help build a report about a specific occurrence. This includes during a fire, smoke, or fumes incident.

The following information is a guide and does not replace formal cabin investigator training.

This is a collection of advice from our Cabin Safety Bulletins series. You can read our full technical documents at Cabin Safety Bulletins.

The investigation process 

The International Civil Aviation Organization (ICAO) defines the difference between accidents and incidents. The definitions include:

• accidents are evacuations where occupants sustain serious injuries
• incidents are evacuations without injuries or aircraft damage.

A cabin safety investigator analyses all aspects of an incident. This includes cabin crew members and passenger actions during the incident. 

To recognise safety deficiencies and lessons learned, an investigation looks at the: 

• cabin environment
• relevant systems and equipment on board.

Investigations can end in recommendations related to operator. This includes:

• procedures
• fatigue (for example scheduling practices)
• training, safety and emergency equipment
• aircraft systems.

ICAO Annex 13 – Aircraft Accident and Incident Investigation has the Standards and Recommended Practices (SARPs)

Annex 13 says the aim of accident or incident investigations is to prevent future accidents and incidents.

The Annex also states an investigation is to never apportion blame or liability.

The investigation process includes the gathering, recording and analysis of all relevant information.

You should collect, deliver, and manage your investigation report by:

• preparing for the investigation
• collecting data
• analysing data
• presenting findings and recommendation
• continuously improving performance.

Some occurrences may need a partial investigation report rather than a full report.

Cabin investigator role

As the cabin investigator, you are responsible for examining and documenting the factors that affect the survival of occupants involved in:

• accidents
• incidents
• occurrences.

A cabin investigator is also responsible for determining factors that affect the safety of a flight. This includes factors that contribute to an occurrence and its outcomes.

For example, the operator changed a policy or procedure and didn’t train crew members to support the change.

Other cabin investigator responsibilities include:

• acting as the expert in the aircraft accident or incident investigation. As a cabin safety expert, you should focus on:
  • cabin interior and emergency equipment design
  • safety and emergency procedures
  • cabin safety
  • occupant protection and related issues
• provide an insight into survival factors such as emergency response search and rescue. For example, an investigator can look into:
  • the characteristics of the crash site (remote location or mountainous region)
  • if the occurrence took place at an aerodrome
  • how the rescue operations responded to the incident and managed the occurrence
• conducting surveys, special studies, and creating proposed safety recommendations and testimonies
• documenting, analysing and evaluating survival factors including:
  • cabin safety and cabin crew training
  • occupant protection, airport operations
  • airport and community emergency management factors that may come up during an investigation
• determining requirements for special tests, studies and technical help
• directing and monitoring these activities and evaluating their findings in terms of relevancy to contributing factors and occupant survivability
• developing a formal report with findings from the investigation. This includes supporting documents, photographs, records, charts, and diagrams
• handing the report in on time, making sure it’s technically correct, and accurately reflects the findings
• identifying safety recommendations and contributing factors
• liaising with authorities.

Types of occurrences

Operators should define the occurrences investigated. Examples include:

• inadvertent slide deployment
• malfunction of aircraft systems or safety and emergency equipment
• a medical event involving a crew member or passenger
• spillage, leakage, or any occurrence to do with the transport of dangerous goods
• occurrences that endanger an aircraft’s operation or cause danger to people or property
• an unanticipated emergency landing
• use of fire extinguishing or suppression agents
• evacuation of crew, passengers or both
• safety and security occurrences. This may include bomb threats, hijack, or security breaches
• an unruly passenger.

Interviewing crew members

The aim of the interview is not to apportion blame but to improve cabin safety and survivability.

The person interviewed should describe an account of what happened. The account should be in their own words without interruption or coercion.

After crew members have given their account, ask follow-up questions to see if you need any further information.

Read our full list of questions to ask crew members.

During the interview, you should consider:

• gathering and reviewing information related to events before, during and after the occurrence
• determining a series of basic questions
• coordinating roles of other investigators if they are in the interview
• verifying all required documents and equipment available to crew
• applying interview protocols
• stating clear aims and clarifying roles for the investigation
• establishing and maintaining an atmosphere of open communication and mutual respect
• being flexible and supportive to the interviewee’s needs
• documenting information in an accurate, complete, and detailed manner
• managing time.

Interview cabin crew as soon as possible after the occurrence and should provide a written statement to you.

Crew members may be re-interviewed later if necessary.

The interview should discuss:

Interviewing passengers

Interview passengers as soon as possible after the occurrence.

They may be re-interviewed later if necessary. You can also send questionaries to passengers to gather information remotely.

Read our full list of questions to ask passengers.

The passenger interview should discuss:

Conducting other interviews

You may need to interview maintenance and ground service if there were systems failures. This may help in gathering any information needed for the investigation. 

You may consider interviewing: 

• off-duty flight crew members 
• cabin crew supervisors 
• instructors 
• firefighting personnel 
• witnesses 
• close relatives. 

Fire, smoke, or fumes

There are other considerations when investigating an onboard fire, smoke, or fumes event inflight or on the ground not the result of impact. 

The fire, smoke, or fumes category includes: 

• fire, smoke, or fumes due to a combustive explosion from an ignition source. This includes from dangerous goods in the cabin or the cargo hold 
• fire, smoke, or fumes from system, component failures, or malfunctions in the flight deck, cabin, or cargo area 
• fumes contaminating the outside air fraction of the ventilation air supplied to the cabin or flight deck. 

You need to reconstruct the sequence of events when investigating a fire, smoke, or fumes event with as much detail as possible. Events you need to reconstruct include: 

• pre-flight activities and actions taken before the fire, smoke, or fumes  
• cabin crew tasks performed tasks to detect and remove fire hazards before and during the flight. This includes cabin surveillance to find or watch for potential sources of fire. 

When investigating a fire, smoke, or fumes make sure you also consider: 

Description of the occurrence

• suspected source of the fire, smoke, or fumes at the time 
• how and when occupants became aware of the fire, smoke, or fumes, 
• effect of fire, smoke, or fumes on occupants. This includes burns, difficulties seeing or breathing, other injuries and their reactions 
• increase, decrease or change in conditions in the cabin or flight deck as the occurrence progressed. This includes locations in the cabin where smoke became denser and level of visibility in the cabin or flight deck 
• difficulties experienced during the occurrence. This may include difficulty in finding the source of the fire 
• what activities were taking place in the cabin at the time. Did the fire occur during a meal service, clean-up, or rest? 

Passenger and cabin crew actions

• who first became aware of the situation. This may be a passenger or crew member
• what did passengers or crew see or smell? This can include description of visible flames (colour and height), characteristics of the smoke (density and size) and odours in the cabin
• immediate actions by the cabin crew after they became aware of the fire, smoke, or fumes
• flight crew and cabin crew actions. This includes including firefighting procedures and communications procedures applied by the crew and passenger actions
• any actions that reduced the risk of injuries from fire, smoke, or fumes. This can include:
  • relocating equipment. This includes moving oxygen bottles, alcoholic beverages and passenger baggage from the vicinity of the fire
  • relocating passengers
  • instructing passengers to breathe into a cloth
  • crowd control
• how and when injuries were treated.

Policies, procedures, and response

• the role and effectiveness of systems and equipment used by cabin crew to fight the fire and manage the situation. This includes how easy it was to access equipment, equipment used by cabin crew, and inoperative equipment
• damage sustained by the aircraft or in the cabin that affected the safety of occupants
• emergency response after landing. This can include firefighting and medical services at the airport.

Decide if the cabin crew acted according to the operator policies, procedures, and approved training programs. This includes managing the passengers and working with other flight and cabin crew members.

You need to find out whether crew followed the operator’s policies and procedures.

You also need to make sure policies and procedures were effective in helping the cabin crew to respond to the situation.

This includes cabin crew safety training program content for firefighting.

Your review should look at any specific hands-on and simulated exercises. You can also analyse other sources of information to find contributing factors.

Building a report following a fire, smoke, or fumes occurrence

Use our Cabin safety incident analysis for advice on building your report. 

Information to help you write your report includes:

• general information
• operator documentation
• documentation of the State Aviation Authority
• documentation from other sources
• aircraft — cabin specific
• human performance — cabin crew
• human performance — passengers.

List of question to ask passengers and crew

We have collated a list of questions to ask passengers and flight crew during investigations.

The list includes:

• questions for passengers
• questions relating to the fire, smoke, or fumes occurrence for passengers
• questions relating to the fire, smoke, or fumes occurrence for cabin crew.

Read the full list of questions.

Further information

You can report defects through our Defect Reporting Portal. You can also contact direct on 131 757 and ask to speak to a cabin safety inspector.

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