The Federal Aviation Administration has warned pilots about tall trees near Hilton Head Island Airport that could pose a danger to approaching planes.
The agency has also barred three types of instrument landing procedures at the airport at night because the trees have encroached on a safety zone for descending planes.
Daytime landings are not affected because pilots can fly with visual flight rules, according to FAA spokeswoman Kathleen Bergen. The most common type of instrument landing into the airport is still allowed, she said.
The notice, which Beaufort County officials learned of Friday, hasn't yet affected commercial or general aviation at the airport.
However, it could create problems under certain circumstances, county administrator Gary Kubic said.
"The end result could be nighttime closure of the Hilton Head Airport, especially in poor weather conditions," he said Monday.
The county requested a waiver for the notice Friday but was denied.
Joe Mazzei, a pilot and vice president of the county Airports Board, said pilots making an instrument landing use an approved downward trajectory when preparing to land. Although that "landing slope" has a built-in margin for error, based on the FAA warning, he said pilots flying at the low end of that slope can't be assured they won't strike something on approach.
Although the effect on airport operations appears minimal for now, the warning is likely to rekindle a years-long debate about tree trimming and removal near the airport off Beach City Road.
County officials have long been concerned about trees in the approach path, Kubic said, and previous tree-cutting efforts have sparked protests from residents. Last year, residents pledged to fight what they referred to as "indiscriminate trimming."
The county has asked consulting firm Talbert, Bright and Ellington to survey areas around the runways to determine if the FAA assessment of tree height is correct. From there, the county would prepare a strategy to remove the obstructions. It's not clear how much the survey will cost.
Hilton Head town manager Steve Riley said the town is ready to work with the county but first needs to learn more about the scope of the problem.
In addition to the trees, a warning light has gone out on a 260-foot-tall communications tower about 17 miles from the runway, the FAA notice said.
Attempts Monday to reach a spokesman for Piedmont Airlines, which operates several daily flights at the airport for US Airways, were unsuccessful.
Follow reporter Casey Conley at twitter.com/IPBG_Casey.