NASA has green-lit a new project that hopes to take the “boom” out of supersonic boom. Its Commercial Supersonic Technology Project recently asked industry teams to submit designs for a supersonic aircraft that will only emit a “heartbeat,” a soft thump instead of the disruptive and sometimes damaging sonic boom that is currently unavoidable with faster-than-sound flight.
According to The Guardian, Lockheed Martin Aeronautics have emerged as the winners of this initiative. They will now submit a preliminary design concept for NASA’s Quiet Supersonic Technology (QueSST) initiative, which will eventually produce the first in a new series of so-called “X-planes” – high-speed aircraft designs dating back to 1945. For their effort, the American company will be given $20 million over 17 months to help bring its creation to life.
“It’s worth noting that it’s been almost 70 years since Chuck Yeager broke the sound barrier in the Bell X-1 as part of our predecessor agency’s high speed research,” said the head of NASA, Charles Bolden, in a statement. “Now we’re continuing that supersonic X-plane legacy with this preliminary design award for a quieter supersonic jet with an aim toward passenger flight.”
Sonic booms are the result of the compression of sound waves through the air. When a jet begins accelerating towards the speed of sound, the air in front of it becomes increasingly compressed. These compressed chunks of air rapidly merge into a single shock wave. As it generates a vast amount of sound energy upon forming, this shock wave is heard as a boom.
A sonic boom may sound cool, but they can actually be quite destructive, particularly to glass windows. Some members of the public have also said that sonic booms cause livestock to go berserk for prolonged periods of time, but these claims are difficult to substantiate.
In addition, military aircraft aim to be both speedy and stealthy, but whenever they reach that magic airspeed of 1,236 kilometers per hour (768 miles per hour), the accompanying thunderclap gives away their position. Removing the sonic boom from supersonic aircraft travel is, therefore, a major priority for NASA.
Although the new announcement doesn’t give any hints as to how the sonic boom will be muffled, it may build on concepts outlined in a 2013 NASA e-book. It points out that between 2003 and 2004, pelican beak-shaped nozzles were added to the front of experimental supersonic jets, which disrupted the formation of pressure waves.
Less intense sonic booms were generated as a result of this modification. Importantly, those on the ground only heard a strange rumbling noise – something known as a “boom carpet” – rather than an explosion of sound.
Once the new QueSST X-plane designs are built, they will be tested out by flying them over populated areas, before surveying the general public about the flights. A scaled-down version of the new plane might debut as early as 2020.
Sonic booms, apart from in exceptional military circumstances, are banned over civilian areas. However, if the new designs ultimately prove to be unobtrusive to those living below, commercial supersonic air travel could finally be up and running again.