Serious Incident in Civil Aviation

A serious incident is an aviation safety occurrence whose circumstances indicate a high probability that an accident nearly occurred, but accident-level consequences did not result. Under the Aircraft (Investigation of Accidents and Incidents) Rules, 2017, the distinction between an accident and a serious incident lies principally in the result of the occurrence.

When an occurrence becomes an accident

An occurrence associated with aircraft operation is classified as an accident when it produces at least one prescribed consequence, subject to exclusions specified in the Rules.

• A person suffers fatal or serious injury because of being in the aircraft, direct contact with it or exposure to its jet blast.
• The aircraft sustains damage or structural failure that adversely affects its strength, performance or flight characteristics and normally requires major repair or replacement.
• The aircraft is missing or completely inaccessible.

Test for a serious incident

A serious incident involves circumstances showing a high probability of an accident, but none of the consequences necessary for accident classification materialises. It is therefore a near-accident category, not merely any operational irregularity.

• The Schedule gives illustrative cases such as a near collision requiring an avoidance manoeuvre, narrowly avoided controlled flight into terrain, and certain operations on a closed or engaged runway.
• An incident is the wider category of an occurrence, other than an accident, that affects or could affect operational safety; a serious incident is its high-risk subset.
• The same event may be classified as an accident if its outcome crosses the prescribed injury, damage or missing-aircraft threshold.

Investigation purpose and institutional role

The Aircraft Accident Investigation Bureau (AAIB) investigates aviation occurrences within the framework of the Rules. The investigation seeks to prevent future accidents and incidents; its purpose is not to apportion blame or liability.