FAA L-807
L-807 type primary wind cones are required for airfields without a 24-hour air traffic control tower (ATCT), whether ATCT is full or part-time.
Title 14 CFR Part 139 Airport Certification requires that an airfield must have a wind cone that provides surface wind direction information to pilots. If an L-807 primary wind cone is not visible to pilots on approach and takeoff at each runway end, airfields must employ L-806 supplemental wind cone(s).
If the airfield is open for air carrier operations at night, internally light all wind cones. The illuminated wind cone must present a constant brightness to the pilot. The primary wind cone will likely be located within a segmented circle so that it is readily visible to pilots.
Dimensions
Size 1 – 8′ (2.5 m) in length and 18″ (0.45 m) in throat diameter
Size 2 – 12′ (3.75 m) in length and 36″ (0.9 m) in throat diameter
Fabric
The windsock’s fabric may be cotton, a synthetic material or a blend of the two, and may be coated. The fabric must be water repellent and may be natural (white), yellow, or orange in color. No lettering or logos allowed. The manufacturer must certify that the fabric meets the following requirements:
a. Minimum breaking strength: Warp – 150 pounds (667 N); Filling – 150 pounds (667 N). The method 5102 of FED-STD-191A can be used to determine the minimum breaking strength.
b. Good or better colorfastness as determined by Method 5671 of FED-STD-191A.
Structure
The type L-807 support may be hinged at its base or near its middle so the wind cone and light fixture can be serviced from the ground. When the support is mounted in place, it must withstand, without damage, a moment of not less than 3200 pound-feet (4340 N m) when the force is applied parallel to and 16 feet (4.8-m) above the surface to which the support is attached. This support may be used only where allowed by airport design standards published in AC 150/5300-13, Airport Design.
References
FAA AC 150-5390-2 – Heliport Design
FAA AC 150/5340-30 – Design and Installation Details for Airport Visual Aids
FAA AC 150/5345-27 – FAA Specification for Wind Cone Assemblies
