Environmentalists are opposed to the mission. Quiet supersonic technology would reduce noise pollution, but supersonic travel still burns more jet fuel than a typical commercial flight.
A 2022 report from The International Council on Clean Transportation found that supersonic aircraft use seven to nine times more fuel per seat-kilometer. “Supersonic transport is like putting Humvees in the sky,” said Jeff Ruch of Public Employees for Environmental Responsibility. The advocacy group sent a letter to NASA in January arguing that supersonic aviation would prevent the industry from achieving carbon neutrality by its self-imposed goal of 2050.