Definition
A method of controlling the aircraft primarily by interpreting the cockpit flight instruments rather than by looking outside at the natural horizon. The pilot establishes and maintains attitude, altitude, heading, and airspeed by reading the attitude indicator, altimeter, heading indicator, airspeed indicator, and related instruments.
Plain English
Flying by what the instruments on the panel are telling you, instead of by what you can see out the window.
Context Anchor
Seen in flight training syllabi and lesson plans for tasks where the student must control the aircraft from the instrument panel instead of mainly looking outside.
Derivation
Instrument comes from an older Latin word meaning a tool or piece of equipment. Reference comes from a Latin word meaning to carry back or point back to something. Together, the phrase means the instruments are the thing the pilot looks back to for guidance and control.
Why Pilots Care
Enables safe and precise control of the aircraft in clouds, at night, or in low visibility where outside references cannot be trusted.
Intuition Check
Do not read reference as a book citation or a casual mention. Here, reference means the source the pilot uses to judge and control what the aircraft is doing.
Example Sentence 1
The student practiced straight-and-level flight using instrument reference while wearing a view-limiting device.
Example Sentence 2
Maintaining level flight by instrument reference requires constant small corrections to the attitude indicator and altimeter.