Definition
A display element on an electronic flight instrument that shows the projected rate at which the aircraft will be turning a short time in the future, based on its current roll rate and bank angle. It typically appears as a moving marker or arrow extending from the heading indicator, showing where the heading will be in roughly six seconds if the present rate of turn is maintained.
Plain English
A small pointer on the heading display that predicts where the aircraft's nose will be pointing a few seconds from now if you keep banking the way you currently are. It helps the pilot lead a turn and roll out on the desired heading.
Context Anchor
Seen on glass cockpit displays while scanning heading, bank, and turn performance during instrument flight.
Derivation
"Trend" comes from an old word meaning "to turn or roll," and in modern use it means "the direction something is going." A trend indicator shows where a value is heading next, not just where it is now.
Why Pilots Care
It lets the pilot anticipate and correct turn rate before the aircraft actually reaches the wrong rate, improving heading accuracy.
Grounding Statement
During a turn, the indicator gives a short visual preview of the heading change that is already developing.
Intuition Check
Do not read “trend” as a command to turn. It is a prediction based on what the airplane is already doing, not an instruction from the display.
Example Sentence 1
As the heading bug approached the trend indicator's tip, the pilot began rolling out to level off on the new heading.
Example Sentence 2
Watching the turn rate trend indicator helped maintain a standard-rate turn without overshooting.