Pentagon to Track Helicopter Noise
Under provisions in the recently enacted National Defense Authorization Act, the Pentagon will be charged with tracking helicopter noise within a 30-mile radius of Reagan National Airport in Northern Virginia. This will include Washington, D.C., and portions of Maryland.
Several congressman in the region inserted the provision into the $740 billion legislation because they have long lamented the “steady rotor din over the nation’s capital and surrounding suburbs.” The big question is: Once the data has been collected, what will actually be accomplished? Much like in the Los Angeles Basin in California, the competing pressures of crowded airspace and the aviation needs of public safety and law enforcement limit practical and safe options.
The amount of helicopter traffic over Northern Virginia, D.C. and Maryland is substantial, according to data recently released in a Government Accountability Office (GAO) report that details the scope of helicopter activity in that area. Between 2017 and 2019, there were 88,000 helicopter flights conducted by 50 separate operators in an area that includes three large hub airports, 11 regional airports, and 55 heliports. Military, law enforcement and air ambulance providers accounted for nearly 80 percent of these flights.
Operators include the FBI, U.S. Park Police, the U.S. Air Force, U.S. Army, U.S. Coast Guard, U.S. Marine Corps, Virginia State Police, Maryland State Police, D.C. Metro Police, Fairfax County Police and Prince George’s County Police.
The GAO study enumerated a variety of factors in the growth of the helicopter noise problem in the region, what operators already have done to mitigate noise, and the difficulties with any further reduction due to the area’s highly restricted and complex airspace. For example, the Pentagon tightened restrictions as to who was authorized to use its heliport, thereby cutting the number of flights originating there from 226 in 2016 to 124 in 2019. Other operators have told crews to refrain from making tight turns and other maneuvers that exacerbate helicopter noise.
In general, helicopter flights in the region adhere to an established network of 25 fixed routes in place since the 1980s that overfly rivers and major freeways to mitigate aircraft noise. But the nature of D.C.’s highly secure and regulated airspace often works at cross purposes with that goal.
This is particularly true in the airspace near Reagan National, where the GAO notes, the “FAA further limits the maximum altitudes for helicopters where helicopter routes overlap with commercial passenger airplane operations to ensure the safety of all aircraft. As a result, helicopters in these areas may fly as low as 200 feet above mean sea level.
Overall, other than measuring helicopter noise, not much can be done. In a December 2020 letter to the GAO, U.S. DOT deputy assistant secretary for administration Keith Washington said, “Significant reductions in helicopter noise in the National Capital Region will be challenging since the majority of operations are military, law enforcement, and medevac service providers.”