Definition
A runway slope in which the runway surface rises along the direction of takeoff or landing. Gradient is expressed as a percentage representing the change in runway height divided by runway length; a positive value indicates an uphill slope in the direction of travel.
Plain English
The runway goes uphill in the direction you are rolling. Taking off uphill takes more distance because gravity is working against you.
Context Anchor
Seen in runway performance discussions, airport data, and takeoff or landing planning when runway slope affects aircraft performance.
Derivation
Gradient comes from the Latin gradus, meaning step or slope. Positive here simply marks the direction of the slope (uphill in the direction of travel), not that the slope is good. An uphill runway is rarely good news for performance.
Why Pilots Care
An uphill slope increases the distance needed for takeoff and reduces landing rollout distance, directly affecting performance calculations.
Grounding Statement
If you stand at one end of the runway and the pavement rises away from you, that direction has a positive gradient.
Intuition Check
Positive does not mean “good” here. It means the runway elevation is increasing in the direction being measured.
Example Sentence 1
The Chart Supplement listed a positive gradient of 1.5 percent on Runway 27, so the pilot added extra margin to the calculated takeoff distance.
Example Sentence 2
Landing on a runway with a positive gradient shortens the rollout because the upslope helps slow the aircraft.