XB-1 has completed three supersonic flights without creating an audible sonic boom on the ground. Sound waves bend when traveling through air with different temperatures. Due to the colder temperatures at high altitude, the sound waves make a U-turn in the atmosphere.
US commercial airlines have had no accidents since February 2009, equivalent to 13.3 trillion passenger miles. The total flight distance without accidents equals 535 million trips around Earth or 28 million round trips to the Moon.
Boom Supersonic will deliver the passenger aircraft Overture, flying at 1,300 miles per hour (Mach 1.7), to airlines in 2029. A journey between New York and London will take 3 hours and 40 minutes, compared to today's 7 hours.
The engine is designed to run on liquid natural gas which costs one-tenth of traditional jet fuel and emits 30 percent less carbon dioxide.