Why don’t we have supersonic aircraft any more? Although commercial supersonic air travel kicked off in the 1960s with the arrival of the Concorde, since that jet was retired in 2003, there are no supersonic jets in common civilian usage any more.

NASA engineers fired the engines on the X-59 research aircraft in advance of planned test flights to determine if the aircraft can reduce sonic booms and make supersonic flight over land quieter.

NASA's revolutionary X-59 jet is steadily progressing toward its first flight test after completing a set of engine run tests at the storied Lockheed Martin Skunk Works facility in California.

NASA’s supersonic X-59 aircraft has taken another critical step toward flight, as its engine was powered up successfully on October 30. Developed by Lockheed Martin's Skunk Works for NASA's Quesst mission,

A try called Quesst Vid The aircraft NASA hopes will usher in a new generation of transport that's supersonic but also relatively quiet has fired up its engines for the first time as a test.… The X-59 Quiet Supersonic Technology (Quesst) airplane has been designed to generate what the agency refers to as a shaped sonic boom,