FAA supersonic flight proposal faces backlash over noise metric

The US Federal Aviation Administration is facing pushback over its proposal to end the decades-old prohibition on civilian supersonic flight over land. The plan would allow supersonic aircraft to operate as long as the sonic boom they generate stays within a specified "overpressure" limit.

Critics say that measure does not properly capture how sonic booms are actually perceived by people on the ground. Environmental organizations including the Sierra Club and Earthjustice have urged the agency to withdraw the proposal entirely, with Earthjustice attorney Amanda Lineberry saying it undermines the FAA's legal obligation to shield the public from aircraft noise.

Daniel Rutherford of the International Council on Clean Transportation said he was surprised the FAA put forward what he called a weak rule, noting that a United Nations panel had already rejected the overpressure metric back in 2014 because it fails to measure loudness or annoyance. He suggested the approach could invite legal challenges.

Concerns are not limited to environmental advocates. According to the article, some within the aviation industry have also expressed unease with the metric, even as they broadly support easing restrictions on supersonic travel.

The FAA has not responded directly to the criticism but said it would consider all comments submitted before finalizing the rule. The agency banned civilian supersonic flight over land in 1973 because of concerns about sonic booms, and has in recent years signaled interest in revisiting that restriction, with momentum building since mid-2025.