What are the common causes of aviation accidents according to investigation results?

The common causes of aviation accidents as identified by various investigation results primarily involve human error, mechanical failure, and environmental factors.

Human error is a significant contributor, as it encompasses a wide range of mistakes made by pilots, air traffic controllers, and maintenance personnel. These errors can result from miscommunication, inadequate training, decision-making under pressure, or failure to follow established procedures.

Mechanical failure refers to the breakdown of aircraft systems or components, which can be due to design flaws, poor maintenance, or age-related wear and tear. Such failures can critically impair the aircraft's ability to operate safely and lead to accidents.

Environmental factors include weather conditions such as turbulence, icing, or poor visibility, which can adversely affect flying conditions and pose risks to safe flight operations.

In contrast, the other options focus on indirect factors or aspects less directly related to the immediate causes of accidents. Weather patterns and pilot training do play roles in aviation safety but are more specific elements under the broader categories identified in the correct answer. Costs and insurance policies pertain to the financial side of aviation rather than accident causation. Lastly, pilot personality types and flight schedules, while they might influence operational efficiency or crew resource management, do not represent the primary causes of aviation accidents as established by investigative