The Federal Aviation Administration wants to scrap the rule that has kept civil supersonic aircraft from flying over the United States for more than half a century, if the aircraft can keep their booms from bothering people on the ground.
In a rulemaking action dated June 30, 2026, the FAA proposed replacing the 1973 ban with an interim noise certification standard. The new test would cap sonic boom overpressure at the surface below 0.11 pounds per square foot. That is the agency’s proposed line between a prohibited boom and one it would allow over land.
The change follows President Donald Trump’s June 6, 2025, executive order directing the government to support a return of supersonic civil flight. The Trump administration has argued that modern aircraft could avoid the disruptive booms that made earlier overland supersonic tests politically radioactive.
What the FAA is measuring
A sonic boom is the pressure wave created when an aircraft flies faster than sound. The FAA’s proposed metric focuses on the pressure that reaches the ground, rather than on a human-rated loudness scale.
The agency cited flights by Boom Supersonic’s XB-1 demonstrator using a technique called Mach cutoff. In those flights, the aircraft flew just beyond supersonic speed at high altitude while relying on atmospheric conditions that refracted its shockwaves upward, keeping them from reaching the surface as a conventional boom.
That is a very different claim from Concorde’s old operating model. Concorde, which carried commercial passengers across the Atlantic from 1976 to 2003, produced about 1.94 pounds per square foot of overpressure while flying at Mach 2 at 52,000 feet, according to figures cited in the FAA discussion.
NASA has said public reaction may begin between 1.5 and 2 pounds of overpressure, while its fact sheet says one pound should not damage buildings or other structures. NASA also says people have experienced between 20 and 144 pounds without injury when supersonic aircraft flew below 100 feet.
The objection is about annoyance, not broken windows
Dan Rutherford, senior director at the International Council on Clean Transportation, told Aviation Week that the FAA’s chosen metric is weak. He said United Nations experts discarded overpressure as a standard in 2014 because “it doesn’t actually measure loudness or annoyance.”
“I’m honestly surprised that the FAA would propose a rule this weak,” Rutherford told the publication.
Congress is moving on a related track. The Supersonic Aviation Modernization Act passed the House on March 24, 2026, and is waiting for a Senate vote. The bill would require the FAA to permit overland supersonic flights when an aircraft is operated so that no sonic boom reaches the ground in the United States.
NASA is testing a different yardstick
NASA and Lockheed Martin are working on the X-59 Quesst, an experimental aircraft shaped to turn the usual boom into what NASA describes as a quieter thump. NASA evaluates that work using perceived level decibels, or PldB, and has set a goal of demonstrating thumps around 75 PldB, roughly comparable to a car door closing from about 20 feet away.
A NASA test pilot and mission integration manager has said future X-59 flights over US communities are intended to collect public feedback that could help regulators decide what level of supersonic noise people will tolerate.
The FAA says it can still revise the proposed rule before trying to finish it by mid-2027. The agency also plans another proposal this year covering takeoff and landing noise for supersonic aircraft.
A rule change does not make an airline
Legal permission would solve only one of supersonic aviation’s problems. Concorde cut New York to London trips from about seven hours to under three, but heavy fuel use made profitable operation difficult, even before accounting for more than $2.8 billion in development costs shared by the British and French governments.
Boom Supersonic is developing a passenger aircraft called Overture and says it aims to deliver the first aircraft to customers by 2029. American Airlines, Japan Airlines, and United Airlines have signed commercial agreements giving them options to buy the aircraft.
Boom has also moved into natural gas turbines for AI data centers. CEO Blake Scholl has suggested that revenue from that business could help fund Overture development. United Airlines CEO Scott Kirby has said he gives Boom a “50/50” chance of getting the aircraft flying.
This story draws on original reporting from Ars Technica.
