FAA Lighting Standards
The Federal Aviation Administration (FAA) has revised its technical standards, and based on the change in certain FAA lighting standards, expects that thousands of birds may be saved each year.
What does the FAA have to do with lighted structures and how will the change save avian lives?
One of the little known authorities which is assigned to the FAA is the review of proposed buildings and towers to determine whether that structure will interfere with the navigable airspace. PART 77—SAFE, EFFICIENT USE, AND PRESERVATION OF THE NAVIGABLE AIRSPACE requires that the proponent of such construction submit an application which defines precisely where the edifice will be located. In the process of the evaluation, the FAA may recommend, among several alternatives, that the proposal include certain lighting to help pilots identify the structure while flying.
According to the FAA, aircraft in normal flight kills as many 9,000 birds a year (and that 2013 estimate is probably rising). Airports are implementing tactics to reduce that incident rate near their facilities. The FAA has given guidance to the sponsors and several airports have initiated creative ways to diminish the likelihood of such awful encounters. In flight encounters are more difficult to prevent and can have significant consequences, too.
The FAA has looked to its Part 77 powers to further limit the potential harm to birds, particularly migratory ones which tend to fly at night. Numerous studies found that:
Wildlife biologists and researchers have suggested that migratory birds traveling at night are the primary victims in these collisions with communication towers. Many of the small migratory songbirds tend to travel at night at low altitudes, as it offers the safest conditions for long distance flight. Nighttime migration also offers lower temperatures, less wind and turbulence, and less danger of predators. When these small birds migrate, they typically use their natural instincts to navigate to their destination. Inclement weather or even a light fog or haze can block their view of the horizon and sky, leaving only man-made features for them to use for reference. In most instances, the birds will use bright, prominent lights that they can see in the distance as reference points, and fly to them. Unfortunately, the bright, prominent lights they select are often obstruction lights. Small migratory songbirds can become disoriented once they reach an obstruction equipped with these lights and are unable to determine in which direction to fly to their next destination. As a result, the birds tend to continue to fly around the obstruction in a state of confusion and, in some cases, fly right into the obstruction guy wires. They may also become so exhausted from flying around the tower that they fall to the ground.
After evaluating the proposal, the FAA conducted flight tests in northern Michigan to compare the traditional steady-burning lighting with a variety of different types of flashing lights. The results (PDF) showed that the new configurations that featured flashing lights provided acceptable warnings for pilots and were likely to result in a significant decrease in bird fatalities.
Based on that determination, the FAA updated its Advisory Circular (AC) (PDF) for obstruction marking and lighting in December 2015. New tower lighting schemes should now follow the revised guidance, and operators of towers with the old lighting system should submit plans explaining how and when they will transition to the new standards.
Considering the number of existing Part 77 lighted structures far exceeds the number of Obstruction Evaluations each year and for years to some, there is great potential for avian death reduction in retrofitting the existing steady burn lights NOW.
As with Federal Regulations and with Advisory Circulars, the new rules usually may only set rules prospectively and cannot revise past approvals. The new AD is quoted as indicating that the existing Part 77 tower operators “should” submit proposed introduction of the new lights. The language at issue is most telling; in the absence of “shall” or “must” or even some specific deadline, this is not a mandate and appears to be optional.
Some environmentally concerned Member of Congress ought to consider introducing a bill (a) compelling the replacement of existing steady burning lights by some date certain and/or (b) creating incentives for early installation of the bird friendly lights.