Key Points:
- Boom Supersonic successfully tested “boomless cruise,” a flight mode that allows supersonic travel without a sonic boom reaching the ground.
- The XB-1 test aircraft exceeded Mach 1 three times during its latest flight, with no detectable boom.
- The technology relies on a phenomenon called Mach cutoff, where atmospheric conditions refract the sonic boom away from the ground.
- Boom plans to implement boomless cruise in its upcoming Overture airliner, potentially cutting flight times significantly.
- Regulatory changes will be needed to permit civil supersonic flights over land in the U.S.
- Boom aims to finalize the Overture’s design soon, with a rollout expected in about three years and commercial flights targeted for 2029.
As released by Boom Supersonic in PCMag, Boom Supersonic has achieved a major milestone in the development of supersonic air travel. The Denver-based startup announced that its XB-1 test aircraft successfully flew faster than the speed of sound multiple times without generating an audible sonic boom on the ground—a breakthrough known as “boomless cruise.”
During a flight from California’s Mojave Air & Space Port, the XB-1 demonstrator jet exceeded Mach 1 three times. Boom CEO Blake Scholl highlighted the achievement during a livestream, stating, “We broke the sound barrier not once, not twice, but actually three times—each time without making an audible sonic boom. It’s about how you fly the airplane.”
The boomless cruise concept takes advantage of Mach cutoff, a phenomenon where temperature and wind gradients in the atmosphere cause a sonic boom to refract upward rather than hitting the ground. A 2012 NASA study confirmed that precise control of speed, altitude, and real-time atmospheric monitoring can enable this type of flight.
Boom Supersonic intends to incorporate this technology into its Overture airliner, which is designed to fly at Mach 1.1 to 1.2 over land without disturbing those below. This could shave up to 90 minutes off coast-to-coast flights in the U.S., reducing travel time between New York and Los Angeles from roughly six hours to around four and a half.
To achieve this in routine commercial operations, Boom is developing its Symphony engines with a group of outside manufacturers. These engines will enable Overture to exceed Mach 1 only above 30,000 feet. Additionally, an advanced autopilot system will help maintain optimal speeds based on atmospheric conditions.
Despite this innovation, Boom still faces regulatory hurdles. Currently, U.S. regulations prohibit civilian supersonic flights over land, regardless of noise levels. Scholl has expressed optimism about working with regulators to update these rules. In a social media post, he joked that the company might need to rebrand as “Shhh Supersonic.”
Other companies have pursued similar quiet supersonic flight concepts in the past, such as Aerion, which planned to use Mach cutoff for its AS2 business jet before shutting down in 2021 due to financial difficulties. Meanwhile, Lockheed Martin is developing NASA’s X-59 test plane to explore low-boom supersonic technology.
Experts believe that updating regulations to accommodate boomless cruise could unlock significant economic opportunities. Eli Dourado, chief economist at the Abundance Institute, called it a “small regulatory change that could drive enormous economic growth,” by encouraging investment in high-speed aviation.
Boom’s vision extends beyond boomless cruise. Over international waters, Overture is expected to reach Mach 1.7, cutting transatlantic travel time in half. The company has secured orders from United Airlines (15 jets) and American Airlines (20 jets), though no additional airlines have placed firm orders yet.
Looking ahead, Boom Supersonic plans to finalize Overture’s design within weeks, followed by its Symphony engines in March. The company expects to begin construction in about 18 months and roll out the first Overture in approximately three years, aiming for passenger service by the end of 2029.
While the timeline is ambitious, the potential impact of boomless supersonic flight is significant. If Boom can navigate the challenges of aircraft development, regulatory approvals, and market adoption, it could usher in a new era of high-speed, long-distance travel—without the disruptive noise of past supersonic jets.
