Everyone knows the term ‘sonic boom’, and most people know it’s the noise an aircraft makes (or anything else for that matter) when it breaks the sound barrier. That was pretty much all I knew about it too, I’m no physics major as you might have noticed. So I’ve collated a little bit more info about it and then put a frikkin’ cool video at the bottom to tie it all up.
So as an aircraft cuts through the air it makes a pressure wave at the front and back in the same way that a ship creates a bow and stern wave as it drifts along.
As the plane’s speed increases the pressure waves get more and more compressed until they collapse together and merge. As the craft hits the speed of sound the waves become one and… BOOM!
Mach 1 is about 1,225 Km/h at sea level and at 20 degrees C.
Here’s something a lot of people don’t know: the sonic boom isn’t a one off bang, the boom actually continues for the whole time that the planes is flying at mach speed. It’s just that to an observer on the ground it seems like a single bang because the beast is flying so fast that you only catch a small section.
The pilot and crew are blissfully unaware of the sonic boom, they can’t hear any change at all. That’s probably why they love to do it over built up areas if they get half a chance.
So there you go, a really rough, ready and rushed explanation. There’s a lot more to it of course, but to be quite honest with you I couldn’t be bothered to read anymore about it, it was getting too complicated. I hope you don’t think any less of me, I was just excited about the video really. So here’s the cool footage I promised:
If you want some more great guff and stuff here’s some choice links: