Definition
Flight instruments that sense and display information through physical mechanisms — gyroscopes, springs, diaphragms, gears, and linkages — rather than through electronic sensors and digital displays. Examples include the traditional attitude indicator, heading indicator, turn coordinator, airspeed indicator, altimeter, and vertical speed indicator found in conventional analog cockpits.
Plain English
These are the old-style round dial instruments that work using moving parts inside them, not computers and screens. The needles and pointers move because of physical things spinning, flexing, or pushing on each other.
Context Anchor
Seen in attitude flying when comparing traditional round flight instruments with electronic flight displays.
Derivation
Mechanical comes from the Greek mēchanē, meaning machine or device with moving parts. The phrase emphasizes that these instruments produce their readings through physical machinery — moving components inside the case — as opposed to electronic processing.
Why Pilots Care
Pilots must recognize these instruments to predict simultaneous failures during vacuum or pressure system malfunctions and switch to backup or partial-panel techniques.
Analogy
Like the difference between a wind-up wristwatch with gears and a smartwatch with a screen — both tell time, but one does it with moving parts you could feel ticking, the other with electronics.
Intuition Check
Do not read “mechanically-generated” as meaning the instrument was manufactured by a machine. Here it means the instrument’s indication is produced by moving physical parts inside the instrument.
Example Sentence 1
The training aircraft had mechanically-generated instruments, so the student learned to recognize gyro precession in the heading indicator.
Example Sentence 2
The airspeed indicator remained usable because it is a mechanically-generated instrument that relies only on pitot-static pressure.