A Real-Life photo for the 'plane fans

[Pecan]

Half-listening to the news on the radio I just heard about a (smaller than Antares) 'explosion' that scared the people of South-East England today.

Not much of a story to it (it was just a sonic boom) but that's one-hell of a well-timed photograph!

[RogueMason]

Huh, that article says RAF Typhoon jets, but the picture shows F18 Hornets. Oh, the annoyance...

Anyway, I'm not so sure taking that picture would have been down to timing. I think that the only reasonable way that those Hornets would have been pictured breaking the sound barrier would have been because it was the air force recording the jets on film; they'd have just grabbed a frame from the footage to give us what we see here (it looks like a still from some film footage anyway). If it was just a photograph, though, then I agree; very well-timed.

[RocketscientistV]

South-East huh. Why do I have to be on school holiday! I could have heard it at my boarding school!

[Tommygun]

This photographer spent five years going to airshows trying to get this picture with a still camera.

He took eight photos in about 2 seconds to get it.

http://www.weather.com/news/science/jet-speed-sound-joe-broyles-photographer-20141014

I used to live next to a military training area and heard sonic booms all the time, but the biggest I have ever heard were the double sonic booms when the shuttle would land at Edwards Air Force Base.

[Nibb31]

I don't understand what is newsworthy about fighter jets making a sonic boom. They do it all the time, although they usually have regulatory limitations for routine flights.

The picture attached to the article, as usual, is a stock photo that is totally unrelated to the incident. The vapor cone phenomenon is due to condensation at transonic speeds but isn't necessarily related to breaking Mach 1.

[ZedNova]

Don't people in England ever have air shows? Or is that an american only thing?

[Kryten]

Some of the largest. Farnborough in particular is very big for the industry, though not so much for the public.

[PakledHostage]

Anyway, I'm not so sure taking that picture would have been down to timing. I think that the only reasonable way that those Hornets would have been pictured breaking the sound barrier would have been because it was the air force recording the jets on film; they'd have just grabbed a frame from the footage to give us what we see here (it looks like a still from some film footage anyway). If it was just a photograph, though, then I agree; very well-timed.

For the record, aircraft do not just generate shock waves (heard on the ground as a sonic boom) while transitioning to supersonic flight. While it is true that you only hear one "boom" (sonic booms from high altitude aircraft actually sound a lot like thunder) as a supersonic aircraft goes by, the guy a few dozen kilometers down the road will hear it too. He'll just hear it a minute or so later than you did as the aircraft passes his location. Much like the bow wave of a boat, the shock travels with the aircraft as it flies along.

I have experienced this personally. About a dozen years ago, while sailing a northern route across the Atlantic, we heard the Concorde's sonic boom many times. Sometimes more than once a day. This despite being thousands of kilometers from where the Concorde would transition to/from supersonic flight. You could recognize it as a sonic boom by the clap of thunder coming out of the clear blue sky, followed by the sound of far-off jet engines.

And also, as Nibb pointed out, a vapor cone can form while an aircraft is flying below supersonic speeds (TAS). Here's a video of an F18 developing a vapor cone during a high speed pass at an airshow in the US. Notice that there's no sonic boom associated with the pass:

Edited October 30, 2014 by PakledHostage
Fixed a spelling mistake. Stupid autocorrect...