Silent supersonic passenger jets

AMERICAN space agency Nasa and aerospace company Lockheed Martin have introduced an experimental “quiet” supersonic (see Word of the Week) aircraft that could help revolutionise passenger flights.

The X-59 test aircraft is central to Nasa’s Quesst project, which hopes to pave the way for a new generation of commercial aircraft that will be able to travel faster than the speed of sound – without much noise.

A major obstacle in the way of supersonic commercial aviation is the sonic boom, a loud explosive noise caused when an aircraft bursts through the sound barrier.

Supersonic flights over land can be very disturbing to people down on the ground – which is why such flights are currently banned by aviation authorities in America and many other countries.

The X-59 test aircraft is set to take to the skies later this year and is expected to fly at 1,4 times the speed of sound (about 1 488km/h).

The aircraft is a big step forward in Nasa’s quest to contribute to the development of relatively quiet supersonic passenger jets.

DESIGN & TECHNOLOGY

Thanks to the X-59’s design and advanced technology, it will be able to break through the sound barrier with just a soft sonic thud (sonic thump) instead of a thunderous sonic boom.

The plane’s thin, pointed nose – that occupies almost a third of its length – will break up the shock waves that normally accompany supersonic speed. It’s these shock waves that cause the boom.

Engineers also placed the cockpit almost halfway down the length of the craft and the aircraft doesn’t have windows at the front.

To help with visibility they added an eXternal Vision System through which pilots have an excellent view of everything outside and around the aircraft via high-resolution cameras and a 4K monitor.

The narrow, streamlined wing design helps reduce wind resistance and the engine is mounted on top, which gives the X-59 a smooth underside and helps prevent shock waves merging behind the aircraft and causing a sonic boom.