Definition
A flightpath in which the aircraft maintains a constant heading and a constant altitude, with the wings level and no climb or descent.
Plain English
Flying in a straight line, at the same height, with the wings flat. The aircraft is not turning, climbing, or descending.
Context Anchor
Seen in instrument flying when using bank control to keep the airplane from drifting into an unwanted turn.
Derivation
Straight comes from an old word meaning stretched out or direct. Level comes from the idea of being even or horizontal. Together, they point to a flight path that does not curve sideways and does not move up or down.
Why Pilots Care
Forms the stable reference from which all instrument corrections and maneuvers begin; loss of it leads to disorientation and altitude or heading deviations.
Intuition Check
Do not read straight-and-level as just looking visually neat. Straight means no turn; level means no climb or descent.
Example Sentence 1
After leveling off at 6,000 feet, the pilot trimmed the aircraft for a straight-and-level flightpath before contacting the next controller.
Example Sentence 2
After a turbulence bump, small aileron inputs were used to restore straight-and-level flightpath before resuming the assigned heading.