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Comment by hannasanarion | Hacker News Reader

Are you confusing sonic booms with regular loud aircraft? Sonic booms over land are illegal in most countries. The US military only ever does supersonic exercises far offshore.

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I'm not the person you are replying to, but there is a possible explanation if the person is American. In 1964 the FAA organized an experiment to perform supersonic fly-overs of Oklahoma City over a period of 6 months. Quoting from Wikipedia "the experiment was intended to quantify the effects of transcontinental supersonic transport (SST) aircraft on a city, to measure the booms' effect on structures and public attitude, and to develop standards for boom prediction and insurance data."

Link to the wiki page if you are curious

https://en.wikipedia.org/wiki/Oklahoma_City_sonic_boom_tests

Here are some highlights

- The US Airforce performed ~8 booms per day between 7am and the afternoon

- In the first 14 weeks, 147 windows in the city's two tallest buildings were broken

- An attempt to lodge an injunction against the tests was denied by a district court judge, who said that the plaintiffs could not establish that they suffered any mental or physical harm and that the tests were a vital national need

- Testing was paused for a time when activist groups sought a restraining order against the testing

- The Saturday Review published an article titled The Era of Supersonic Morality, which criticized the manner in which the FAA had targeted a city without consulting local government

- All this public pressure ended the testing early

- There were 9,594 complaints of damage to buildings, 4,629 formal damage claims, and 229 claims for a total of $12,845.32, mostly for broken glass and cracked plaster.

> There were 9,594 complaints of damage to buildings, 4,629 formal damage claims, and 229 claims for a total of $12,845.32, mostly for broken glass and cracked plaster.

That doesn’t seem much money. Even with inflation which makes it $110,600ish it seems very reasonable. I can imagine one difficult window install making up this much.

I also grew up with constant sonic booms. There is no way to mistake a loud aircraft for them. This is like mistaking a loud engine with a gun shot.

I grew up in Germany, and whatever the laws said (probably sonic booms were illegal), they didn't apply for the allied troups (mostly British and American in my region). So jet fighters going supersonic pretty close to the ground were a rather common thing, you might hear one once a week or so.

(Technically, Germany became only with the 2+4 treaty in 1990 a fully souvereign nation, formally ending the occupied state after WW2)

The U.S. military does supersonic flights over land, too. For example, see page 39 of the R-2508 Complex Users Handbook[1], the section titled "Supersonic Operations". The R-2508 complex[2] is an airspace around the area of Edwards Air Force Base in California.)

1. https://www.edwards.af.mil/Portals/50/R-2508%20User%27s%20Ha... 2. https://www.edwards.af.mil/About/R-2508/

Yeah in France we have them too, I live not too far from Mirage/Rafale air bases, and they fly over sometimes. I remember it was more common around the 2000s, nowadays I hear it less than once a year. I think it happened over Paris last year and people freaked out, calling for a bomb and everything.It was for an interception mission.

https://www.nytimes.com/2020/09/30/world/europe/boom-noise-r...

I remember hearing sonic booms while on holiday in wales as a child, just looked it up and it looks like a couple still happen every year

I assume the military can decide to be exempt from the law if they want

They can in the UK. Back in January, the QRA Typhoons chasing an unresponsive aircraft back in January went right overhead at 10000 ft at supersonic speeds. That was loud: https://www.cambridgeindependent.co.uk/news/huge-sonic-boom-...

I grew up in a remote part of northern California, and I can assure you that every so often a military jet would would fly right over our house at super sonic speeds(and very low altitude, barely above the tree tops).

It was mind numbingly loud and obnoxious-the entire house would shake and rattle and you couldn't hear anything but the rumbling.

I sincerely doubt the jet in question was flying at supersonic speeds right above tree tops. Couple of reasons, at low altitude most military jets can only handle mach 1.2 or so at the cost of massive fuel consumption. Any sort of long distance flight at low altitude, supersonic speeds would waste massive amounts of fuel. Additionally all aircraft are significantly less maneuverable at supersonic speeds which is a bad combination with being close to the ground. Lastly and probably most importantly sonic booms are really really loud. As in they can at least in theory kill people if in close contact(not aware of this actually happening at any point, but there was a cold war project to use a low flying supersonic aircraft as an anti-tank weapon). Point is if they actually where supersonic I would be surprised if you didn't have some form of hearing damage. Also shaking and rattling is not consistent with a sonic boom, just normal jet noise.

It happens accidentally from time to time. It's easier to do (accidentally or on purpose) in some planes, and engine-variants than others.

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