What Concorde breaking the sound barrier actually sounded like

It's almost hard to believe there was once a commercial jet that flew at supersonic speeds.

This was, of course, the Concorde - and it still holds the record for the fastest commercial flight across the Atlantic.

There were plenty of reasons for its demise, including a high-profile and fatal crash, but for a long time, it was the quickest way to get between the US and Europe.

The reason it was so fast was that Concorde could go at supersonic speeds, faster than 660 miles per hour, the sort of velocity that brings with it a famous phenomenon called a 'sonic boom'.

This happens when something moves faster than sound itself, creating shockwaves in the air, and you can clearly hear what Concorde sounded like as it hit that speed in this amazing vintage clip:

It shows a distant Concorde flying in a blue sky, twin jet trails clearly visible, but without any sound, since the plane is so far from the camera. Then, all of a sudden, two huge booms ring out like claps of thunder.

You can hear the shocked reactions of other onlookers in the video as they process what they just heard, and it's obvious how incredibly loud it was - even through older video equipment.

It was this staggering noise that created another part of Concorde's reputation - that living under its flight path could be a sleep-disturbing nightmare (depending on the flight times, since Concorde didn't actually run all that many times per day).

Locals constantly complained of the noise of Concorde flights compared to other planes, and you can understand why when you hear the booms for yourself.

Mirrorpix / Contributor/ Getty

That didn't mean everyone hated it, though - in fact, one commenter under that YouTube video reminisced about it: "Always remember hearing the booms as a kid growing up in South Wales and thinking 'there she goes'."

Another viewer had a similar story from the other side of the Atlantic: "I remember when the Concorde used to fly over my grandpa's old house in Queens. He lived next to Kennedy Airport. Everyday at 6pm and 6am, my grandpa claimed the Concorde came. I only had the pleasure of experiencing a flyover once. The furniture shook as it approached, followed by the most deafening roar you've ever heard, and every car alarm on the block going off simultaneously. It was awesome."

With its cone-like shape and sleek design, the Concorde remains one of the most distinctive and recognizable commercial jets ever - and who knows, maybe supersonic travel will be back on the table sometime soon.