A plane crash occurs when an aircraft unexpectedly loses control and impacts the ground or water. This can happen due to various factors, including mechanical failure, human error, or adverse weather conditions. The consequences of a plane crash can be severe, often resulting in injuries or fatalities among passengers and crew. Investigations into plane crashes are conducted by agencies such as the National Transportation Safety Board (NTSB) in the United States. These investigations aim to determine the cause of the crash and improve aviation safety. Findings can lead to changes in regulations, training, and aircraft design to prevent future incidents.