Aircraft Accident and Incident Investigation — Page 492, Lesson 659

I want to walk you through the opening definitions of accident and incident investigation, because these exact words are what the entire investigation system is built on. Let's take them one at a time. First, the Incident. An incident is an occurrence, other than an accident, associated with the operation of an aircraft which affects or could affect the safety of operation. So the key idea is that it's something that happens during aircraft operation that either did affect safety, or had the potential to affect safety — but it falls short of being a full accident. It's the broad category that catches everything that isn't an accident but still matters. Next, the Investigation itself. An investigation is a process conducted for the purpose of accident prevention. That's the whole point — not blame, not punishment, prevention. The process includes the gathering and analysis of information, the drawing of conclusions, including the determination of causes and, when appropriate, the making of safety recommendations. So you collect data, you analyse it, you work out what caused the event, and then — where it's appropriate — you issue safety recommendations so the same thing doesn't happen again. Now, a Serious incident. This is an incident involving circumstances indicating that an accident nearly occurred. So it's the close call — the event where, by luck or by a narrow margin, a full accident was avoided. The book points you to paragraph 26.9 for examples, but the definition itself is that an accident nearly happened. Then we have Serious injury, and this one is very precise because it's a legal threshold. A serious injury is an injury sustained by a person in an accident which meets any of several criteria. Let me walk through each one. It requires hospitalization for more than 48 hours, and that hospitalization must commence within seven days from the date the injury was received. So it's not just any hospital stay — it's more than 48 hours, starting within a week of the injury. Or, it results in a fracture of any bone — except simple fractures of fingers, toes, or nose. So those minor fractures are excluded, but any other bone fracture counts. Or, it involves lacerations which cause severe haemorrhage — that's severe bleeding — or nerve, muscle, or tendon damage. Or, it involves injury to an internal organ. Or, it involves second or third degree burns, or any burns affecting more than 5% of the body surface. Or, it involves verified exposure to infectious substances or injurious radiation. So any one of those criteria being met makes the injury "serious" in the legal sense, and that classification matters because it determines how the event is reported and investigated. Finally, we have three States — and these are crucial because they define who has jurisdiction, who gets to investigate. The State of design is the State having jurisdiction over the organization responsible for the type design. So that's the country that oversees the company that designed the aircraft type. The State of manufacture is the State having jurisdiction over the organization responsible for the final assembly of the aircraft. Note the difference — design is the design authority, manufacture is the final assembly line. And the State of occurrence is the State in the territory of which an accident or incident occurs. That's simply where the event physically happened. So when you put it together: the incident is the event, the investigation is the prevention-focused process, the serious incident is the near-miss, the serious injury is the legally defined threshold of harm, and the three States tell you which authorities have a stake in the matter. These definitions are the foundation — every report you'll ever read, every investigation you'll ever be part of, uses these exact terms.