5 ms·
0.11 pound per square foot is what is being proposed. That's 108 decibels. Which is between standing next to a lawn mower and standing next to a car horn. I do
by foobarqux 3mo ago
0.11 pound per square foot is what is being proposed. That's 108 decibels. Which is between standing next to a lawn mower and standing next to a car horn. I don't see how anyone will tolerate that in practice.
https://www.omnicalculator.com/physics/db https://www.omnicalculator.com/physics/db
- gedy 3mo agoBecause it's not continuous sound in one spot like a leaf blower is.
- foobarqux 3mo agoThere is a substantial noise beyond the initial boom which is very loud even relative to the main boom. But even just a half second of a car horn going off right next to you every so often is intolerable.
- HlessClaudesman 3mo agoPeople finding a way to tolerate what was previously considered intolerable is pretty much the story of civilization.
- auntienomen 3mo agoI'd argue that civilization is the story of people finding ways to overcome what they previously had to tolerate.
- michaelmrose 3mo agoIf supersonic flight is so expensive that less than 1% of the population can enjoy it its not clear why the rest of us ought to tolerate it
- ranger_danger 3mo agoYou have to start somewhere before you can build towards an economy of scale that makes it affordable. If people used your same logic about regular airplanes, we wouldn't be using them today.
- michaelmrose 3mo agoSupersonic flight will never be suitable for the masses compared to normal flight due to basic physics. It will always require much more expensive planes and more fuel. It's not more viable now wealth inequality just means that there are more rich people to benefit.
- logicchains 3mo ago>Supersonic flight will never be suitable for the masses compared to normal flight due to basic physics. It will always require much more expensive planes and more fuel. You could have used the exact same argument for normal flight 100 years ago. Supersonic flight being more expensive than normal flight doesn't mean it will always be too expensive for the masses unless you assume there'll be no more economic growth ever.
- throwaway85825 3mo agoPhysics doesnt change. It will always cost more energy to fly faster.
- fragmede 3mo agoRelatively, absolutely, but look at computers. Yes, more computing still costs more than less computing. Physics hasn't changed, but the cost of computers has. I have, in my hand, for part of a couple months of middle class wages, more computing power than existed in the world in 1960.
- 3mo ago
- bobthepanda 3mo agoIt's worth noting that the initial supersonic bans came as a result of sustained sonic boom testing over the same population: https://en.wikipedia.org/wiki/Oklahoma_City_sonic_boom_tests https://en.wikipedia.org/wiki/Oklahoma_City_sonic_boom_tests
- throwaway2037 3mo agoI disagree. The more that I travel, the more that I notice the trend: The richer you become, the quieter you become. Even in the same country, income level seems to strongly correlate with how loud you are in public (and private).
- cindyllm 3mo ago[dead]
- dylan604 3mo ago> But even just a half second of a car horn going off right next to you every so often is intolerable. You must not have a neighbor with a car whose alarm constantly goes off at random points throughout the day right outside your window. You eventually don't notice it. Speaking from experience
- budman1 3mo agolive by a railroad track. takes about 6 months till you don't notice it. at all.
- fragmede 3mo agoDepends on the frequency and duration. Lived near some tracks for years and what got me was waking up in the middle of the night for that freight train that was irregular. The regular passenger train I got used to though.
- makeitdouble 3mo agoTo state the obvious, it's better if it's calm: https://www.eea.europa.eu/en/analysis/indicators/health-impacts-of-exposure-to-1 https://www.eea.europa.eu/en/analysis/indicators/health-impa... On getting used to it, people adapt in that they stop consciously noticing the noise, but it's still constantly processed and grinding on one's environmental awareness.
- craftkiller 3mo agoI actually do, and I still notice it every time. Some asshole across the street rides a motorcycle and every day he revs his motorcycle which sets off the alarm of some other asshole's van.
- asdfadsfgfdda 3mo agoIt’s not accurate to convert .1 psf to dB because it’s an impulsive shape, not a continuous tone. And human loudness perception depends on how smooth (low frequency) the shape is
- foobarqux 3mo ago> It’s not accurate to convert .1 psf to dB because it’s an impulsive shape, not a continuous tone. And human loudness perception depends on how smooth (low frequency) the shape is Sorry can you explain more? It's just the definition of dB (?) And it's less impulsive than you imagine, go to youtube to listen to the sonic boom + continuous roar. The FAA has no criteria about the "texture" of the sound and there is no reason to believe the allowed planes will differ substantially in this respect compared to every other supersonic aircraft in the past.
- asdfadsfgfdda 3mo agoOn a typical day, the atmospheric pressure varies by maybe 150 Pa, or 3 psf. By definition, that’s 137 dB. But it’s imperceptible because the rate of change is so low.
- foobarqux 3mo agoObviously it is assumed we are talking about frequencies in the range of the audio spectrum (which a sonic boom is). Your point has nothing to do with the dB scale.
- atoav 3mo agoYeah nah. For all relevant level metering you use a A-weighting curve (weighting the frequencies by human ear sensitivity) so that is not how any of that works.
- LoganDark 3mo agoA sonic boom doesn't exactly average out over the length of the day, though, does it?
- LargoLasskhyfv 3mo ago> That's 108 decibels. > I don't see how anyone will tolerate that in practice. Oh! Really? https://earinc.com/gunfire-noise-level-reference-chart/ https://earinc.com/gunfire-noise-level-reference-chart/
- xoa 3mo ago...yes, really? Gun fire is indeed stupendously, dangerously loud, which is why we have suppressors and heavy hearing protection for them. And there are indeed significant public/legal fights around outdoor gun ranges that end up near habitation (even if it's not the range's fault at all but rather because construction moved towards it). So I'm not really seeing how that's an argument that people not wearing earpro would be fine with regular 108 dB booms over where they live/work. People aren't happy even about small engine noise and rightfully so, and it's one of a few core reasons for switching to electric.
- ranger_danger 3mo agoMost gunshots people hear are not right next to them and so won't be anywhere near 108 dB to them.
- bobthepanda 3mo agoalso, there are neighborhoods with extended amounts of gun violence and discharges and I can't say that the residents "don't mind it"
- throwaway85825 3mo agoIn this case they mind getting shot at by stray fire, the noise is a secondary concern.
- fragmede 3mo agoKeeps rent down tho.
- 27183 3mo agoMy only experience with a sonic boom was in D.C. a few years ago when fighters were scrambled to intercept a learjet which had depressurized and everyone onboard was unconscious. I believe it ultimately crashed somewhere in VA or WV. Anyway, my windows were open and the "blast" was startlingly loud, but not like a detonation. More of a gentler push like a large fireworks explosion. It was both a loud sound and a pressure wave sufficient to move the curtains in the windows. There were emergency services responding all over the city looking for the source of an explosion. I guess we'll get used to it if that kind of things becomes routine? I'm not sure.
- dylan604 3mo agoMy guessing from the couch would be they were further away than you might have thought. I was up in the mountains when a couple of fighters flew close with a boom, and it was one of the loudest things I have experienced.
- 27183 3mo agoYeah that's entirely possible, I have no idea what their actual flight path was.
- throwaway85825 3mo agoYou could have checked adsb exchange.
- WalterBright 3mo agoBack in the 1960s (!) the military would fly supersonic over the town I lived in. I always enjoyed the boom. I would also open the window during a thunderstorm or go sit on the porch because I enjoyed the incredible electric display and the booms.
- throwaway85825 3mo agoMilitary gets away with things that private industry doesn't. Supersonic passenger planes would be flying every day on a schedule, far far more than military. Commercial planes are also rated for far more flight hours.
- WalterBright 3mo agoYes, the military ones were infrequent. I'm sure it would get annoying if it was too often. > Military gets away with things that private industry doesn't. For good reason. You cannot train for hedgehopping to avoid radar detection without flying low with firewalled throttles.
- throwaway85825 3mo agoOverland private supersonic travel should not happen, it would just be a massive unpriced negative externality. The lower the plane flies the fewer people end up hearing the boom. The denser air also requires an absurd amount of fuel to fly through. Commercially uneconomical. Even the military only uses low level supersonic for a last dash to the target.
- randallsquared 3mo agoWhen Boom was testing last year, the sonic boom never reached the ground, as I recall. That can be arranged at higher altitudes, but doesn't work at low ones.
- throwaway85825 3mo ago
- m463 3mo agoIt seems like that is the limit. the proposal: https://www.faa.gov/newsroom/ARM-260115-001_Supersonic_NPRM_06-10-26.pdf https://www.faa.gov/newsroom/ARM-260115-001_Supersonic_NPRM_... ... also alludes to new designs where the boom doesn't reach the ground. It also talks about primary and secondary booms. Will folks with these planes eliminate risk of going > .11 psf by having the boom stay off the surface?