Often Uncharted, Difficult To See

The FAA Safety Team (FAAST) has published an advisory about the hazards of MET (Meteorological) Towers that are often erected quickly and can be in place for months or years. The towers are put up to help gather meteorological information before the construction of a wind farm or other alternative energy project.

Towers generally range in height from 30, 50, 60 and 80 meters tall. Any tower less than 200 feet in height is not required by regulation to be lighted. At this time there is no standardized notification system in place to indicate when and where these towers are erected.

These are not posted in any Airport Facility Directory, NOTAMS, etc. unless they interfere with airport operations.

MET Tower FAA Photo

According to the FAA, a sponsor proposing any type of construction or alteration of a structure that may affect the National Airspace System (NAS) is required, under the provisions of Title 14 Code of Federal Regulations (14 CFR part 77, Objects Affecting Navigable Airspace), to notify the FAA by completing the Notice of Proposed Construction or Alteration form.

Generally, any structure that exceeds an overall height of 200 feet above ground level (AGL) or exceeds any obstruction standard contained in 14 CFR part 77 should be marked and/or lighted. Because of the lighting requirement, most METs are just under 200 feet AGL. However, even if the tower is under 200 feet AGL, or meets 14 CFR part 77 standards, the FAA may still recommend marking and/or lighting because of its particular location.

Wind Farm Dept. of Interior Photo

The wind turbines that follow the MET towers can also be difficult to see. An inter-agency memo issued by the Department of the Interior and the Forest Service on low-level flight operations says that wind turbine generators are usually painted white because it’s the most effective daytime early warning device. Other colors, such as light gray or blue, appear to be significantly less effective in providing daytime warning. Daytime lighting of wind turbines, regardless of height, is not required, as long as the structures are painted in a bright white color or light off-white color.

FMI: www.faa.gov