Sec. 139.307 - Unpaved areas.
(a) Each certificate holder shall
maintain and promptly repair the surface of each gravel, turf, or other
unpaved runway, taxiway, or loading ramp and parking area on the airport
which is available for air carrier use as follows:
(1) No slope from the edge of the
full-strength surfaces downward to the existing terrain shall be steeper
(2) The full-strength surfaces shall
have adequate crown or grade to assure sufficient drainage to prevent
(3) The full-strength surfaces shall be
adequately compacted and sufficiently stable to prevent rutting by
aircraft, or the loosening or buildup of surface material which could
impair directional control of aircraft or drainage.
(4) The full-strength surfaces must have
no holes or depressions which exceed 3 inches in depth and are of a
breadth capable of impairing directional control or causing damage to an
(5) Debris and foreign objects shall be
promptly removed from the surface.
(b) Standards and procedures for the
maintenance and configuration of unpaved full-strength surfaces shall be
included in the airport certification manual or the airport certification
specifications, as appropriate, for compliance with this section.