An in-flight breakup is a catastrophic failure of an aircraft structure that causes it to break apart in mid-air. This can result in the death of all occupants, and/or the destruction of the aircraft. In-flight breakups are rare but devastating events that could be caused by a variety of factors.
In some instances, faults in the design or manufacturing could create weak points or stress concentrations in the structure could cause a breakup. Constant use and repeated loading and unloading cycles on the aircraft can lead to fatigue cracking. In other cases, pilot error[1] or weather conditions could cause the aircraft to experience conditions beyond what it can withstand. In other cases, the breakup is caused by sabotage or terrorism damaging critical systems or components.