United Airlines Holdings Inc. said Thursday it has reached an agreement with Denver, Colo-based aerospace company Boom Supersonic to add its aircraft to its global fleet. Under the terms of the deal, United will acquire 15 of Boom’s “Overture” airliners, as soon as Overture meets its safety, operating and sustainability requirements with an option to acquire an additional 35 aircraft. “The companies will work together on meeting those requirements before delivery,” United and Boom said in a joint statement. “Once operational, Overture is expected to be the first large commercial aircraft to be net-zero carbon from day one, optimized to run on 100% sustainable aviation fuel (SAF).” It is expected to roll out in 2025, fly in 2026 and start to carry passengers in 2029. The Boom aircraft can fly at twice the speed of today’s faster airliners, said the statement. Future planned routes include a three and a half hour flight from Newark to London, Newark to Frankfurt in four hours and San Francisco to Tokyo in just six hours. United shares were down 1.3% premarket, but have gained 39% in the year to date, while the U.S. Global Jets ETF has gained 22% and the S&P 500 has gained 12%.

Market Pulse Stories are Rapid-fire, short news bursts on stocks and markets as they move. Visit MarketWatch.com for more information on this news.