Definition
On an airport sketch or airport diagram, slope is the gradient of a runway expressed as the change in elevation along its length, usually shown as a percentage. A positive value means the runway rises in the direction of travel; a negative value means it falls. Slope is depicted on the diagram when the runway gradient is 0.3 percent or greater.
Plain English
How much a runway tilts uphill or downhill from one end to the other, shown as a percentage on the airport diagram.
Context Anchor
Seen on airport sketches, airport diagrams, and runway information when checking the physical layout of an airport before departure or arrival.
Derivation
Slope comes from older English words meaning to slant or lean. That helps here because a runway slope is the runway's slant, measured instead of just guessed by eye.
Why Pilots Care
Affects takeoff and landing distance calculations; an uphill slope increases the runway length required.
Intuition Check
Slope does not just mean a runway looks steep. In aviation, it is a measured uphill or downhill change, and even a small slope can matter.
Example Sentence 1
The airport diagram showed a runway slope of -0.6 percent, so the pilot expected a slightly downhill takeoff roll.
Example Sentence 2
Landing on a downslope runway requires less distance but demands careful speed control.