Environmental groups weighing in on the FAA’s supersonic special flight authorization proposal are expressing everything from concern to outright opposition, and many individuals are using the proposal as a platform to complain about flight pattern changes resulting from new NextGen procedures.

In response to the notice of proposed rulemaking that would facilitate special flight authorizations primarily for supersonic aircraft testing, the Center for Biological Diversity (CBD) filed comments signed by 27 other public health and environmentalist groups that began with the headline "Prevent Devastating Harms from Super-Polluting Supersonic Aircraft."

“With existing technology, there is no way to advance ‘safe and efficient operation of supersonic aircraft.’ Supersonic aircraft would fuel the global climate crisis and threaten Americans with lasting damages from extreme air and noise pollution,” said the groups, which include organizations such as Friends of the Earth, Sierra Club, National Resources Defense Council, and Nurse Alliance of SEIU Healthcare.

The groups expressed concern supersonic operations will burn five to seven times the amount of fuel as subsonic designs and international carbon dioxide emissions limits. “We are in a climate emergency. Given our limited carbon budget, limited time to act, and urgent need to slash greenhouse pollution from the aviation sector overall, allowing a new class of super-polluting aircraft to enter the sky would be madness. It is obviously inconsistent with the FAA’s obligations to protect public health and welfare,” they said.

Separately, CBD filed comments reiterating the warning of the environmental harm that could result from any testing and urging the FAA to impose a high threshold that involves significant environmental study for each application. “As the FAA grapples with the purported reemergence of civil supersonic aircraft, it must ensure that it takes the devastating environmental impact of these aircraft into account in all action it takes as a regulatory body.”

The center worries that the FAA is mischaracterizing the extent of its obligations under the National Environmental Policy Act of 1969 (NEPA). That policy obligates agencies to take a “hard look” at environmental impacts before deciding whether to pursue a particular federal action, the center said, contending that each application for a special flight authorization would necessitate an environmental assessment (EA) and environmental impact statement (EIS).

It fears that the FAA believes an EA would fulfill its duties. An EA might help the FAA determine whether the application has a finding of no significant impact or, conversely, a significant impact that requires and EIS, CBD explained.

But the center believes that the proposal itself underscores the environmental harm posed by supersonic flight. “Because sonic boom, no matter how ‘quiet’ or insignificant, trails an aircraft in supersonic flight along its entire route, impacts are not limited to land surrounding airports,” the center said, adding, “Wildlife, domestic animals, and built structures and infrastructure are also affected by sonic boom. Exposure to aircraft noise over time is associated with increased risk of high blood pressure and heart disease for adults, and cognitive impairments in children.”

A conclusion that anything less than a full EIS would be inconsistent with science and 50 years of FAA policy, CBD added.

The FAA should use the strictest possible standard, as well as lessons learned from NextGen procedures implementation, added a residents group outside San Francisco that calls themselves the Sunnyvale/Cupertino Airplane Noise Group. “A high hurdle should be met in order to remove this supersonic flight ban, and these new supersonic aircraft should meet stringent airplane noise and fuel-efficiency standards equivalent to newly manufactured subsonic aircraft,” the residents said.

Of chief concern was their experience of the implementation of NextGen procedures in the San Francisco Bay Area Metroplex. “Since the implementation of NextGen, our cities have experienced a problem with aircraft noise. The FAA should not compound this problem by adding supersonic aircraft to the mix while people across the country are still suffering from NextGen.”

They gave a number of recommendations, such as no audible sonic boom at ground level, the application of the same noise and fuel standards for subsonic and supersonic aircraft, and the application of the most stringent sonic boom criteria. They also urged the FAA to keep such operations out of metroplexes (at least 70 miles away) if the aircraft cannot meet the stringent standards.

A majority of the 200-plus comments in the docket of the proposal came from individuals expressing some sort of dissatisfaction with the NextGen procedures implementation.

“We are already impacted by NextGen with flights every two minutes starting at 6 a.m. and going on until late at night. I cannot believe the FAA is now proposing testing supersonic aircraft over land. This will compound the already bad problem of NexGen,” one commenter wrote.

“Ever since NextGen was introduced a few years ago, I have been subjected to excessive noise and air pollution. My home is no longer the sanctuary it was when I first purchased it 20 years ago,” said another commenter. These were examples of sentiments expressed by numerous others.