Mitigating the Impacts of Aviation

A variety of aircraft, including military, commercial, general aviation, and aircraft used for NPS administrative purposes, fly in the airspace over national parks. Although there are many legitimate aviation uses, overflights can adversely affect park resources and values and interfere with visitor enjoyment.

The Natural Sounds Program (NSP) was established in 2000 to help parks manage sounds in a way that balances the various expectations of park visitors with the protection of park resources. The National Park Service works to protect and enhance park resources and visitor experiences, and as a result, the NSP differentiates between the physical sound sources and human perceptions of those sounds.

The combination of physical sound resources, or acoustic resources, at a particular location comprise what is known as the acoustical environment. Acoustic resources include both natural sounds (wind, water, wildlife, vegetation) and cultural and historic sounds (battle reenactments, tribal ceremonies, quiet reverence). The human perception of the acoustical environment is referred to as the soundscape.

HALE Equipment

Equipment at Haleakala National Park used to determine the sound impacts of aviation over the area.

black and white line drawing ATMP

Commercial Air Tour Management Plans

In recent years, the number of airplanes and helicopters flying over national park units has increased dramatically. Aviation activities over parks include general aviation, commercial passenger flights, park maintenance, and fire and emergency operations. Much of the increase in flights over the national parks can be attributed to the growth of the air tour industry. In the 1990s, Congress began to address the increasing number of sightseeing air tours by mandating the Federal Aviation Administration (FAA) and the National Park Service to manage air tours over the parks.

The National Parks Air Tour Management Act of 2000 requires the development of Commercial Air Tour Management Plans (ATMP) for each park in which air tours are conducted. with the exception of the Grand Canyon and its environs, Rocky Mountain National Park, and lands in Alaska. The FAA and Park Service signed a Memorandum of Understanding for the ATMP program in 2004 and recently completed a detailed plan for implementing the program and developing ATMPs. Currently, ATMPs are being developed for Lake Mead National Recreation Area, and Hawaii Volcanoes, Haleakala, Kalaupapa, Mt Rushmore, and Badlands National Parks.

Aviation Air Plan Management Hawaii

Example of a draft Air Tour Management Plan, Hawaii Volcanoes National Park

Additional Laws & Policies

Because the nation’s airspace is managed by the Federal Aviation Administration (FAA), NPS works constructively and cooperatively with the Federal Aviation Administration and national defense and other agencies to ensure that authorized aviation activities affecting units of the national park system occur in a safe manner and do not cause unacceptable impacts on park resources and values and visitor experiences. Cooperation is essential because the other agencies involved have statutory authorities and responsibilities that are recognized by NPS. (Management Policies Chap. 8.4)

Natural Sounds Program

Protection and management of park soundscapes are guided by several important laws and regulations. These laws and regulations form the foundation of Natural Sounds Program.

Advisory Circular 91-36D Visual Flight Rules (VFR) Flight Near Noise-Sensitive Areas

Regulations Regarding Flights Over Charted National Park Service Areas, U.S. Fish and Wildlife Service Areas or U.S. Forest Service Areas

Information Regarding Flight Advisories in National Parks

Landing at National Parks, Monuments, Preserves, Wildlife Refuges and at State Refuges, Critical Habitat Areas, and Sanctuaries