Sec. 77.29 - Airport imaginary surfaces for
(a) Heliport primary surface. The area of the primary surface
coincides in size and shape with the designated take-off and landing area
of a heliport. This surface is a horizontal plane at the elevation of the
established heliport elevation.
(b) Heliport approach surface. The approach surface begins at
each end of the heliport primary surface with the same width as the
primary surface, and extends outward and upward for a horizontal distance
of 4,000 feet where its width is 500 feet. The slope of the approach
surface is 8 to 1 for civil heliports and 10 to 1 for military heliports.
(c) Heliport transitional surfaces These surfaces extend outward
and upward from the lateral boundaries of the heliport primary surface and
from the approach surfaces at a slope of 2 to 1 for a distance of 250 feet
measured horizontally from the centerline of the primary and approach
[Doc. No. 1882, 30 FR 1839, Feb. 10, 1965, as amended by Amdt.
77-9, 36 FR 5971, Apr. 1, 1971; 36 FR 6741, Apr. 8, 1971]