Definition
Causes of an aircraft upset that originate from the airplane itself or its systems rather than from environmental conditions or pilot inputs. Examples include autopilot malfunctions, flight control system failures, asymmetric flap or slat extension, trim runaway, and powerplant or thrust anomalies that disturb the airplane's attitude.
Plain English
Things going wrong with the airplane or its equipment that push it into an unusual attitude, as opposed to bad weather or something the pilot did.
Context Anchor
Used when discussing possible causes of unusual attitudes and airplane upsets during flight training and upset recovery training.
Derivation
Mechanical comes from an old Greek word meaning a machine or device. In this aviation use, it points to the airplane and its systems, not to the pilot’s judgment or the weather.
Why Pilots Care
Pilots must distinguish mechanical factors from pilot-induced or environmental causes so they can select the correct recovery technique and decide whether to declare an emergency.
Intuition Check
Mechanical factors does not mean only engine trouble. Here it means any aircraft system or equipment problem that can help create or worsen the upset.
Example Sentence 1
Asymmetric flap extension is one of the mechanical factors that can roll an airplane into an unusual attitude shortly after takeoff.
Example Sentence 2
Preflight checks are designed to catch mechanical factors before they lead to an in-flight upset.