Wouldn’t the military also be very interested in such a technology?
And, as long as I have your ear, would it be possible for another jet to fly along in the actual boom by matching the first jet’s speed at the right distance behind?
I’ve always wondered about that.
Here’s a clip of a Tomcat fly-by, where you can see the shock wave on the water. There some other footage I saw years ago, of an F-111 (IIRC) flying at supersonic speed across the desert. A very nice shock wave would be seen on the ground, which I think was a better illustration than in the linked video. But I can’t find that one.
Here’s another cool water one.
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Based on what I read in the trade press, the military is a little bit interested in boomless (well low-boom really) flight. IF it provided a way to reduce drag that’d be a performance enhancer. The ideas out there today to solve this problem are net performance reducers. Since the boom trails the aircraft, becoming boomless doesn’t enhance surprise enroute to the target.
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The boom is a pressure wave. It sounds explosive precisely because it isn’t very large from front to back. From the POV of somebody on the ground, the entire event, from rise to decay, lasts a second at most, and often much less. Given the speed of sound is (very) roughtly 1000 fps, that says that by the time the boom gets to ground level it’s less than 1000 feet from leading to trailing edge, and perhaps more like 50 ft for a very sharp boom. Conversely, as it left the generating aircraft, its thickness fore-to-aft was fractions of an inch.
IANA Aero engineer, but I suppos it’d be theoretically possible to “surf” another aircraft along the leading edge of the pressure wave. At least up near the generating aircraft where the pulse is still pretty coherent. Sorta like geese in their V formation, you’d gain some efficiency.
As it left the aircraft the boom was pretty coherent, almost a pure zero-rise-time square wave impulse. By the time it gets to the ground it has been muddied by diffraction and, like distant thunder, takes on a more spread-out rolling sound. How it sounds to your ears is really just a plot of pressure over time. So the target for a trialing aircraft would be bigger, but less useful.
All in all I bet it’d be utterly impractical. You’d have a hard time designing a way of coupling the pressure gradient to the trailing aircraft, and just finding the right place in the sky would be an all but impossible task, not to mention staying there for any usable duration.
I think **Stranger On A Train **has some actual experience with supersonic aerodynamics and if so, he’ll be able to extend my arm-waving here with some actual facts.
When I was quite young, we lived near a test range. So I heard a lot of them, among other interesting sights and sounds. It was always fun when a convoy of military vehicles zipped thru town in a Big Rush to locate something that didn’t end up where it was supposed to. After they cleared out, the high school boys would then go looking around the area they went to see if any “interesting” debris was missed. Lots of wild stories would then circulate after such an event.
Back in the day when just watching supersonic jet fighters maneuver was prime entertainment.
OOooh, I bet some of you guys know my Dad. He worked on the B-1 for Rockwell at Edwards starting in the 70’s. We moved to Lancaster in 1976. He’s been retired for 10 years.
I grew up living in Lancaster, so we frequently hear sonic booms from both airplanes and space shuttle landings.
The one time I got up close passes for the shuttle landing, it rained so it got diverted to New Mexico
Otherwise I was out with the peons in the desert trying to spot the little white spot in the sky that was the shuttle.
I moved in with my dad in Lancaster in 1976. Moved to L.A. in '87. (And up here in '03.)
I watched from the FAA hill. 
(The only problem was that the final stop was obscured by the large Quonset hangars.)
One of my earliest memories is hearing one when we lived in Ft. Worth Texas sometime around '73-'74. I would have been about 5 at the time. It sounded to me like the world was ending. Everyone around us was cringing and looking up at the sky in confusion/fear. It was right around that time I developed a phobia about loud, sudden noises. Coincidence? Dunno.
I wonder if it was a Blackbird? Although in TX it could have been almost anything, I guess.
I lived in Beirut from 2000-2006, and Israeli jets used to buzz the city sometimes; so every once in a great while you would hear a sonic boom from one of the planes. Then in 2006 they bombed the city, so we got to hear a different kind of boom for a while.
It was made illegal to stop Concorde.
Well, that’s what I was told at BAe. 
I’ve heard stories about pilots playing games. Like saying “hi” to their girlfriends or wives".
Also just for fun. Not that they can hear the boom, but for the speed.
Sometimes both. 
I used to hear this on the opposite side of the border. I spent the summer of 1998 in Haifa, Israel during which the Israelis launched one of their periodic assaults on Lebanon. We heard the sonic booms of the jets headed northwards fairly often.
I don’t know about up close, but I live in Orlando(ish) and have heard the shuttle coming home.
I’ve heard louder thunder.
This (and the preceeding one) are probably high-speed sub-sonic flypasts, as there is no boom apparent on the soundtrack, just the normal jet exhaust shear noise. The vapour cone and pressure wave visible on the water are from a phenomenon known as a Prandtl–Glauert singularity, which occur at transonic speeds, when parts of the airflow around the aircraft are at supersonic speeds even though the aircraft itself is not. Really cool looking though!
The last sonic boom I heard was actually mutiple small booms when the pieces of the shuttle Columbia flew over the farm house. It rattled the windows for 20-30 seconds and I went outside to see what was going on. I saw some crooked contrails, but I didn’t know what caused them. It was only later in the afternoon that I turned on the radio and found out what had happened.
Mein Herr worked for a construction company several years ago that would take a bunch of employees and family to a local air show every year. And every year the Blue Angels or whoever was there would do the sneak up and boom right over the line of tents where we were. Hated it every time, and the kids would scream bloody murder, then laugh. I tried to anticipate it every time, but they always got me.
Dang no-job show-offs.
Thats the thing about sonic booms, though. You can’t hear them coming. You can see the plane go over and still not be prepared.
What’s eerie is when it goes over low and is utterly silent. For a few seconds.
Wow I had missed this thread to reply back!
mangeorge - the weird thing is I am in Northeast Mississippi. I don’t know a thing about sonic booms. How far would the sound travel?
And yes, it was frightening because no one could figure out at first if the house had been hit by a car (yes, that has happened and the feeling was similar) or an explosion or what. My dad passed it off as he seemed to know what it was but I can’t imagine hearing that at any random time. I’d look like a chihuahua from all the nervous shaking.
For what it’s worth, the sneak pass part of the Blue Angels’ show, while very fast, is still subsonic.