Basic Concepts — Page 16, Lesson 23

I want to walk you through some foundational concepts in aviation safety culture and human performance. These ideas are central to how we think about accident prevention in professional flying. Let's start with safety culture. There are three types I want you to understand. First, Open Culture. This is where all levels of an organization play an active part in the improvement of the safety culture. Everyone, from the most junior engineer to the chief pilot, is expected to contribute to making safety better. Second, Closed Culture. This is the opposite — where an organization is reluctant to release information on threats, errors, or undesired aircraft states to other agencies. That reluctance can prevent the wider industry from learning from mistakes. Third, National Culture. Both government and ethnic factors influence attitudes towards safety culture. The regulatory environment and the broader cultural background of a country shape how safety is perceived and practiced. Now, what factors promote a good safety culture? Three things: Leadership, Commitment, and Good example. It starts at the top. If the leadership isn't visibly committed and setting a good example, the culture won't follow. Let's move to a critical model — Reason's Swiss Cheese Model. This is one of the most important concepts in aviation safety. James Reason likens human systems to multiple slices of Swiss cheese, stacked together side by side. An organization's defences against failure are modelled as a series of barriers — those are the Swiss cheese slices. The holes in the cheese slices represent individual weaknesses in each part of the system. Crucially, those holes are continually varying in position and size in each slice. They're not static. The system as a whole will produce failures when all of the holes in each slice momentarily align. When that happens, a hazard will pass through all of the holes in all of the defences, leading to a failure. So an accident isn't usually one single mistake — it's a chain of weaknesses that line up at the wrong moment. Now, let's talk about counter measures. All flight crew MUST employ counter measures in order to keep threats, errors, and undesired aircraft states from reducing safety margins in flight operations. This is not optional — it's a requirement. There are two categories of resources we use as counter measures. Hard Resources are physical or procedural tools. Examples include: - Airborne Collision Avoidance Systems (ACAS) — which warns of conflicting traffic - Ground Proximity Warning Systems (GPWS) — which alerts you if you're getting too close to terrain - Standard Operation Procedures (SOPs) — the written procedures we follow - Checklists - Briefings - Training Then there are Human Resources, and here we use a model called ATM — that stands for Avoid, Trap, Mitigate. Avoid means an attempt to foresee potential problems. This is best achieved at times of low workload — when you have the mental space to think ahead. Trap means you deal with threats and hazards as they occur. You catch the problem in the moment. Mitigate means you deal with the consequences of an error that has already occurred. Here's an important point: mitigation feels like failure, but it is, in fact, success — it is the safe option. If you have to mitigate, you're not failing; you're recovering professionally. Finally, let's cover the duties of flight crew in a commercial company. For all flight crew, two key duties: - You must be conversant with and uphold both the laws and regulations of the country and the rules of the company. Ignorance is not an acceptable excuse for any contravention. - You shall obey all lawful commands which the Commander of the aircraft may give for the purpose of securing the safety of the aircraft and of persons or property carried therein, or for the safety, efficiency, or regularity of air navigation. For the Commander specifically: the Commander must maintain familiarity with relevant air legislation, practices, and procedures, together with provisions of the company Operations Manual. That's a personal responsibility that sits with the Captain.