Monday, March 21, 2016

Controlled Flight Into Terrain

Whenever an airworthy aircraft, with all mechanical, electrical, hydraulic, electronic, flight control and automation systems operating normally, wings level, or in a coordinated controlled bank and all crew members at their stations, but is at an altitude where the aircraft encounters ground level, it is called controlled flight into terrain. If all systems are operating normally and within set parameters, there is no possible opportunity for an airplane to crash. Any unscheduled event that leads to an airplane crash is the result of one or more system failures.

All systems are operational without elimination of any required for flight. 

Controlled Flight Into Terrain (CFIT) exists only in a virtual world of perfectionism. CFIT definition of airplane accidents is removing a system from total flight operational systems required to complete the flight, which is the Human Performance System.

As early as the late 50’s Human Performance System analysis were in a beginning stage and included in behavioral studies. Over the years since then, human behavior, or human factors developed into a science of management of the Human Performance System. This system does not only include the last link of events, but is viewed in a Safety Management System as organizational accountability of zero tolerance to compromise aviation safety. During the early days of aviation, human behavior, or Human Performance System, were often assigned to be the cause of accidents and defined as pilot error. Pilot error is not a system failure, but a procedure failure during a specific and last segment of the flight just prior to the crash. As data of accidents and unscheduled events were collected and analyzed over years, the industry realized that human job performance factors are manageable factors of a functional Human Performance System. By the 1990’s human factors in flight was widely accepted as system factors of a safe flight.

On November 28, 1979 a passenger jet crashed into a mountain and the cause was identified as Controlled Flight Into Terrain, since all known technical systems were operating normally. At some point during the flight an unplanned event happened and the airplane crashed.

Systems are often pushed to the limit.
On July 19, 1989 there was a system failure in a passenger jet, which again caused a complete flight control system malfunction. Pilots, or automation were unable to produce yaw, roll and pitch control for a safe flight. During the flight an unplanned event disabled required systems for a safe flight, except for the Human Performance System. Pilots and flight crew were in essence the only viable operational system available to continue the flight.

These two flights produced the end result of an airplane crash. The first one was identified as pilot error, or CFIT, while the second as a technical system failure. Both accidents have one common denominator, which is the Human Performance System. In one accident there was a system breakdown, while with the second accident human performance raised to the challenge in management of technical system failures and went above and beyond expected job performance. Human Performance System is as much as a requirement for a safe flight as operational technical systems. However, when Controlled Flight Into Terrain becomes the cause of accidents, Human Performance Systems are ignored as a requirement system for the completion of a safe flight.