Calculators / Performance / Obstacle Climb Gradient

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Performance

Obstacle Climb Gradient Calculator

Calculate minimum geometric climb gradient needed to clear an obstacle.

Obstacle height above runway

Horizontal distance

Desired margin

Required gradient—

Percent grade—

Angle—

550 feet to gain over 2 NM

A 500 ft obstacle plus a chosen 50 ft margin over 2 NM gives (500 + 50) / 2 = 275 ft/NM, about a 4.53% geometric slope.

This assumes the entered height must be gained over the entire entered distance. It is not a certified obstacle-clearance analysis or a substitute for a published departure procedure.

Formula and method

Required geometric gradient = obstacle height plus desired margin ÷ horizontal distance, with consistent units.