Definition
A vertical, scrolling altitude display on an electronic flight instrument system (EFIS) or primary flight display (PFD) that shows the aircraft's current altitude against a moving scale of altitude values. Current altitude is read from a fixed reference pointer in the center of the tape, with higher altitudes scrolling down from above and lower altitudes scrolling up from below as the aircraft climbs or descends.
Plain English
A vertical strip on a glass cockpit display that shows your altitude. The numbers move up or down past a fixed pointer in the middle, so you always read your current altitude at the center of the strip.
Context Anchor
Seen on the main electronic flight display during the instrument scan, especially in aircraft with glass cockpit instruments.
Derivation
Called a 'tape' because the scrolling band of numbers resembles a strip of measuring tape moving past a fixed marker, similar to a ribbon or tape unrolling.
Why Pilots Care
Provides immediate visual reference for maintaining assigned altitudes and detecting small deviations in instrument conditions.
Analogy
Think of it like a vertical ruler on the screen. The airplane’s current altitude is read at the fixed reference point while the numbers move past it.
Intuition Check
Do not think of tape as something sticky or physical. In altitude tape, tape means a strip-shaped display of altitude numbers.
Example Sentence 1
As the aircraft climbed through 5,000 feet, the altitude tape on the PFD scrolled smoothly past the center pointer.
Example Sentence 2
During the descent the altitude tape scrolled downward steadily as the airplane lost height toward the airport.