Chicago Convention and Annex 13

Annex 13 to the Chicago Convention sets international Standards and Recommended Practices for investigating aircraft accidents and serious incidents. Its central principle is that the investigation seeks prevention, not the apportionment of blame or liability, which may be addressed through separate proceedings.

Legal basis and responsibility

Under Article 26, the State where an accident occurs must institute an inquiry in specified circumstances and permit the State of Registry to appoint observers. Annex 13, framed through Articles 37 and 38, elaborates common investigation standards; a contracting State unable to comply with an international standard must notify ICAO of the difference.

• The State of Occurrence normally institutes the investigation, but it may delegate all or part of it to another State or a regional accident investigation organization by mutual arrangement.
• Where the occurrence is outside any State's territory, responsibility generally falls upon the State of Registry.

Conduct and international participation

The investigating State must ensure an investigation with effective independence and provide the investigator-in-charge control over it. It must preserve evidence, protect the aircraft and relevant records, secure custody, and facilitate timely access to the accident site and material.

• The States of Registry, Operator, Design and Manufacture are entitled to appoint accredited representatives and advisers.
• States must provide relevant information, facilities or experts and cooperate in matters such as witness evidence, technical examination and record recovery.
• Investigation activities should be coordinated with judicial authorities without compromising the safety investigation's purpose.

Reporting, safety action and confidentiality

The investigating State must communicate findings through a Final Report and formulate safety recommendations where appropriate. If the report cannot be released within 12 months, an interim statement should be issued on each anniversary explaining progress and significant safety issues.

• Draft reports must be circulated to entitled States for significant and substantiated comments before finalization.
• The Final Report should be made publicly available as soon as possible and forwarded to the States concerned and ICAO where applicable.
• Sensitive investigation records receive disclosure protection so that safety investigations retain access to candid testimony and operational information.
• Safety recommendations are preventive proposals and do not themselves create a presumption of blame or liability.