GeoTechHub
A technical branch of RSA Airfield Consulting, LLC.

FAA Runway Grade Checker

Interactive runway surface, longitudinal grade, transverse slope, drainage, and line-of-sight review.

1

Upload runway elevation CSV

Accepted formats

Wide grid: one station per row with headers such as offset_-75, offset_0, and offset_75.

Long survey: columns named station_ft, offset_ft, and elevation_ft.

Station intervals and lateral offsets may vary. The runway pavement limits must be covered by the uploaded offsets.

2

Analysis settings

Advanced tolerances and screening controls

FAA criteria and calculation basis

Segment longitudinal grade

\[G_i = \frac{E_{i+1}-E_i}{S_{i+1}-S_i}\times 100\%\]

AAC A and B: maximum longitudinal grade is 2.0 percent. AAC C, D, and E: maximum is 1.5 percent, reduced to 0.8 percent within the lesser of the first or last quarter of runway length or 2,500 ft.

Transverse slope

\[S_t = \frac{E_{crown}-E_{offset}}{|x_{offset}-x_{crown}|}\times 100\%\]

AAC A and B: 1.0 to 2.0 percent. AAC C, D, and E: 1.0 to 1.5 percent. The standard configuration is an equal, constant center crown, with specified alternate configurations permitted by the AC.

Runway line of sight

\[E_{LOS}(x)=E_1+5+\frac{x-x_1}{x_2-x_1}\left[(E_2+5)-(E_1+5)\right]\]

The sampled profile verifies that the runway surface does not obstruct the line between points 5 ft above centerline. The required viewing distance depends on whether a full parallel taxiway is available.

Design geometry limitation

Sampled elevations do not uniquely define tangent PVIs, PVCs, PVTs, or theoretical vertical-curve lengths. Those checks are therefore reported as not evaluated instead of being inferred from noisy survey data.