NASA Showed a Photo of a Plane Breaking the Sound Barrier (4 photos)
Not only is the image unique, but so is the aircraft, which is currently undergoing flight tests. 
NASA has demonstrated a unique image of breaking the sound barrier. In order to capture changes in the refractive index of air that are invisible to the naked eye, many factors had to be taken into account, the US space agency reported.
It is noted that such an image requires ideal conditions. NASA used ground-based telescopes with special filters that made air distortions visible using the so-called schlieren method. At the same time, the aircraft must be in a precise location and at a precise time when breaking the sound barrier, so that telescopes can capture the aircraft flying in front of the sun at a speed of about 1,234 km/h. 
It is noted that the unique image also captures a unique aircraft - the supersonic XB-1, which is being developed by Boom Supersonic in conjunction with NASA. The photograph of breaking the sound barrier is needed by specialists to record data on the aircraft's acoustic signature, as well as to analyze its aerodynamics. It is assumed that the XB-1 will be the first American supersonic passenger airliner. And one of the engineers' tasks is to make sure that the sonic boom is not heard on the ground. This is one of the most important conditions for getting permission for commercial flights. Boom Supersonic said that the tests were successful - no sonic boom was heard on the ground.
"We also confirmed that the XB-1 did not produce any audible sonic boom, which opens the way for coast-to-coast flights 50% faster," said Blake Scholl, founder and CEO of Boom Supersonic. 
It is noted that the first commercial flight of the XB-1 is planned for 2029. The company has already received 130 pre-orders from two American airlines and a Japanese airline. 
