Nasa to test ‘quiet’ supersonic flights over Texas(cnn.com)
cnn.com
Nasa to test ‘quiet’ supersonic flights over Texas
https://www.cnn.com/travel/article/nasa-supersonic-flights-testing/index.html
75 comments
There is a fascinating pattern, in aeronautics, whereby the design that works best is almost always inexplicably beautiful. It's as if humans have a broad and innate understanding of aerodynamics, even far past our natural environment. (Contrast that with astrodynamics, where the best design is usually the ugliest.)
> It's as if humans have a broad and innate understanding of aerodynamics, even far past our natural environment.
As a fluid dynamicist, I'd say closer to the opposite is true. The shapes might look good, but ask a person not trained in basic fluid dynamics to explain what makes a particular shape aerodynamic and they'll likely do poorly.
Boundary layer separation phenomena seems to be inherently unintuitive. I can recall talking about aerodynamics with someone very smart but untrained in the field. They seemed focused on the high pressure zone created in front, with no consideration of the size of the low pressure zone in the back. (In a simplified view of the problem.) If the boundary layer separates prematurely, it creates a larger low pressure zone and increases drag. So the shape of the back of an object matters to its drag. There's a reason airfoils are elongated and not just smooth fronts with abrupt ends.
And the intuitive understanding most people have would not suggest that roughening an object could decrease its drag. But this is a well known phenomena explained by boundary layer separation as well.
(Note that I don't know much anything about supersonic aerodynamics and what I say here is only what I know about subsonic aerodynamics. I am not an aerodynamicist, just a guy who works broadly in fluid dynamics.)
As a fluid dynamicist, I'd say closer to the opposite is true. The shapes might look good, but ask a person not trained in basic fluid dynamics to explain what makes a particular shape aerodynamic and they'll likely do poorly.
Boundary layer separation phenomena seems to be inherently unintuitive. I can recall talking about aerodynamics with someone very smart but untrained in the field. They seemed focused on the high pressure zone created in front, with no consideration of the size of the low pressure zone in the back. (In a simplified view of the problem.) If the boundary layer separates prematurely, it creates a larger low pressure zone and increases drag. So the shape of the back of an object matters to its drag. There's a reason airfoils are elongated and not just smooth fronts with abrupt ends.
And the intuitive understanding most people have would not suggest that roughening an object could decrease its drag. But this is a well known phenomena explained by boundary layer separation as well.
(Note that I don't know much anything about supersonic aerodynamics and what I say here is only what I know about subsonic aerodynamics. I am not an aerodynamicist, just a guy who works broadly in fluid dynamics.)
I think you missed his point.
He didn't claim that our innate appreciation for specific forms might imply that we make good decisions about how to find more.
What he did say was that our degree of appreciation for proven designs, founded in evidence, seems to show that, as animals, we have buttons buried deep within us, that these designs manage to push.
We all seem to like the same thing, once someone finds it or figures it out, even without knowing specifically why. Certain shapes and designs seem to transcend language, education, formal training and analytical judgement.
There are rule sets that seem to appeal to us, instictively, and yet spaceships are not bound by those "rules of instinctive appeal" even though qualitatively, we can't state what those rules are or where they come from.
The mystery, regarding where that post-hoc appeal comes from is what's interesting.
Not that people aren't master draftsman, and materials scientists out of the womb.
He didn't claim that our innate appreciation for specific forms might imply that we make good decisions about how to find more.
What he did say was that our degree of appreciation for proven designs, founded in evidence, seems to show that, as animals, we have buttons buried deep within us, that these designs manage to push.
We all seem to like the same thing, once someone finds it or figures it out, even without knowing specifically why. Certain shapes and designs seem to transcend language, education, formal training and analytical judgement.
There are rule sets that seem to appeal to us, instictively, and yet spaceships are not bound by those "rules of instinctive appeal" even though qualitatively, we can't state what those rules are or where they come from.
The mystery, regarding where that post-hoc appeal comes from is what's interesting.
Not that people aren't master draftsman, and materials scientists out of the womb.
I disagree. If efficient designs pushed some buttons in your head in a satisfying way, you'd find people absolutely fascinated by things like the Sears-Haack body:
https://en.wikipedia.org/wiki/Sears%E2%80%93Haack_body
Yet I'm not aware of anyone who is. In fact, the Sears-Haack body is basically a toothpick, which makes it ugly as far as I'm concerned.
There's a simpler explanation for why airplane designs are often beautiful. Ugly designs typically don't sell as well. So designers look for something beautiful and at least reasonably efficient. In this view, there's no particular connection between the beauty of the design and its efficiency.
I know that for car designs, we've known empirically for nearly 100 years how to make a very low drag body shape. And most car shapes on the market are far from optimal. While I've had arguments with people about why the most efficient shapes don't appear on the market (e.g., someone argued they'd have less cargo capacity, which I don't agree with), ultimately, few people want to drive a car that looks like a fish or something else that's strange. I imagine a similar phenomena occurs with planes.
This design is very efficient, but the company folded after about 6 years:
https://en.wikipedia.org/wiki/Aptera_2_Series
Personally, I don't find the design attractive. And I doubt your average HN reader feels as compelled by the design as they do about the latest Tesla, for example.
https://en.wikipedia.org/wiki/Sears%E2%80%93Haack_body
Yet I'm not aware of anyone who is. In fact, the Sears-Haack body is basically a toothpick, which makes it ugly as far as I'm concerned.
There's a simpler explanation for why airplane designs are often beautiful. Ugly designs typically don't sell as well. So designers look for something beautiful and at least reasonably efficient. In this view, there's no particular connection between the beauty of the design and its efficiency.
I know that for car designs, we've known empirically for nearly 100 years how to make a very low drag body shape. And most car shapes on the market are far from optimal. While I've had arguments with people about why the most efficient shapes don't appear on the market (e.g., someone argued they'd have less cargo capacity, which I don't agree with), ultimately, few people want to drive a car that looks like a fish or something else that's strange. I imagine a similar phenomena occurs with planes.
This design is very efficient, but the company folded after about 6 years:
https://en.wikipedia.org/wiki/Aptera_2_Series
Personally, I don't find the design attractive. And I doubt your average HN reader feels as compelled by the design as they do about the latest Tesla, for example.
This continues to invert the premise. The intersection of appealing things and functional things is more interesting that either taken in isolation.
Having an intuitive eye for what's aerodynamic does not mean one is able to explain the physical mechanism behind it.
Explanations aside, the phenomena I mentioned go directly against common intuitions. Those intuitions are not as accurate as people think they are.
That aerodynamics is counterintuitive is fairly well accepted among fluid dynamicists. Watch this classic series of videos from MIT:
https://youtube.com/watch?v=j0rQ4F3f-Ic
I have not watched the videos, but I did read the associated book, and it goes into detail about the counterintuitiveness.
That aerodynamics is counterintuitive is fairly well accepted among fluid dynamicists. Watch this classic series of videos from MIT:
https://youtube.com/watch?v=j0rQ4F3f-Ic
I have not watched the videos, but I did read the associated book, and it goes into detail about the counterintuitiveness.
I would say that this is not specific to aeronautics. It works also for other engineering fields. I find there is always an uncanny beauty in simple, elegant and efficient design usually. Be it software, mechanics or electronics. I am sure it goes as well in other disciplines...
Engineering is a form of Art.
Engineering is a form of Art.
Given that humans are pretty good swimmers and divers, and even have little webbing between fingers and toes, I'd say we have an innate understanding of fluid dynamics rather than aerodynimcs, with aerodynamics being a special case of fluid dynamics.
I.e. we have an innate ability to identify a good swimmer's body, because we as a species are (potentially) good swimmers.
I.e. we have an innate ability to identify a good swimmer's body, because we as a species are (potentially) good swimmers.
More likely that we are exposed to a lot of aerodynamic animals. And we find them beautiful.
ESA engineers have told me: If it looks good it will work well. So they seem to have a lot of experience with this, although their sense of aesthetics might be impacted by their work.
I guess something similar is at play when I think something looks fast, and usually the object is sleek and aerodynamic.
Is there such a thing as astrodynamics? Since there's mostly vacuum in space, can't you have whatever shape you want?
> Is there such a thing as astrodynamics?
Yes, it's a hodgepodge of ballistics, orbital and celestial mechanics, and other factors relating to spacecraft navigation.
Yes, it's a hodgepodge of ballistics, orbital and celestial mechanics, and other factors relating to spacecraft navigation.
Yes, I nearly majored in it. It's basically spacecraft engineering + orbital mechanics and celestial navigation.
Or humans have a natural affinity for smooth surfaces and curves. Objects that happen to be aerodynamically efficient.
The podcast .NET Rocks has several "geek out" episodes, which go into depth about tech. About two years ago they did one on supersonic flight, and I remember a lot of details about quiet sonic bombs there. Well worth a listen if someone wants to learn more about supersonic travel. Actually, all of the geek outs are fantastic.
[Episode summary]
> Concorde is gone, what will replace it? Time for a Geek Out! Richard talks about the aeronautical evolution that led to supersonic airliners, Concorde being the big one that flew from 1976 to 2003. What went wrong? Why did it stop flying? Besides the technological challenges, it all comes down to the sonic boom and laws that make it illegal to fly a civilian aircraft above the speed of sound. Richard talks about how technology has advanced enough now that aircraft can mitigate their sonic boom with specific shapes and flying capabilities. However, in the end, supersonics only get you there faster, typically for more money. Would you pay for to go faster?
http://www.dotnetrocks.com/?show=1286
[Episode summary]
> Concorde is gone, what will replace it? Time for a Geek Out! Richard talks about the aeronautical evolution that led to supersonic airliners, Concorde being the big one that flew from 1976 to 2003. What went wrong? Why did it stop flying? Besides the technological challenges, it all comes down to the sonic boom and laws that make it illegal to fly a civilian aircraft above the speed of sound. Richard talks about how technology has advanced enough now that aircraft can mitigate their sonic boom with specific shapes and flying capabilities. However, in the end, supersonics only get you there faster, typically for more money. Would you pay for to go faster?
http://www.dotnetrocks.com/?show=1286
The place where we ended up in that show is that airlines find that time and again, customers will pay for more luxury rather than time... a regular subsonic flight JFK-LHR is a bit over 7 hours, Concorde cut that to 3:15. But does that matter? People like the idea of getting there faster, but when it comes to actually spending money on it, most wouldn't do it.
A one-way trip on Concorde was about $5000, and for that money, you got an old-school business-class seat (they never updated the interior of Concorde), no overhead bins, no internet access, no entertainment system of any kind. For that same money, you get the all-encompassing cocoon of the modern business-class pod on a 787. It may take twice as long, but you don't care because you're comfortable.
Meantime, we're getting closer to manned hypersonic flight, Mach 5+ with combined cycle engines. Considering the development time necessary for a new airliner, especially with experimental technology like new supersonic engines, I think the LockMarts and Boeings of the world are waiting for more of that technology to mature. It would suck to develop a brand new Mach 2 airliner just in time for someone else to build a Mach 5 airliner.
Also, the Mach 5 designs using ramjets would fly high enough (>80,000 feet) that sonic booms are really not an issue. The SR-71 at Mach 3 and 80,000 feet was virtually inaudible.
Much of the experimentation going on around shaping sonic booms is proving contemporary fluid dynamic models that show that you can "customize" your N-Wave and make the kind of boom you want to make.
Interesting times!
A one-way trip on Concorde was about $5000, and for that money, you got an old-school business-class seat (they never updated the interior of Concorde), no overhead bins, no internet access, no entertainment system of any kind. For that same money, you get the all-encompassing cocoon of the modern business-class pod on a 787. It may take twice as long, but you don't care because you're comfortable.
Meantime, we're getting closer to manned hypersonic flight, Mach 5+ with combined cycle engines. Considering the development time necessary for a new airliner, especially with experimental technology like new supersonic engines, I think the LockMarts and Boeings of the world are waiting for more of that technology to mature. It would suck to develop a brand new Mach 2 airliner just in time for someone else to build a Mach 5 airliner.
Also, the Mach 5 designs using ramjets would fly high enough (>80,000 feet) that sonic booms are really not an issue. The SR-71 at Mach 3 and 80,000 feet was virtually inaudible.
Much of the experimentation going on around shaping sonic booms is proving contemporary fluid dynamic models that show that you can "customize" your N-Wave and make the kind of boom you want to make.
Interesting times!
This is exciting. Concorde's withdrawal from active service back in 2003 dragged the aviation industry back by at least a couple decades imo, though I concede that its critics are right in pointing to the fact that the aircraft was an absolute disaster when it came to its carbon footprint and overall eco-efficiency. [0]
This project, if successful, could be a 'Wright brothers' moment for supersonic travel and would dramatically cut down inter-continental travel time, thereby propelling the aviation industry into stratosphere and increasing the global financial throughput as a result of decreased flying duration -- in the next decade or so.
[0] https://www.tapatalk.com/groups/concordesst/concorde-s-envir...
This project, if successful, could be a 'Wright brothers' moment for supersonic travel and would dramatically cut down inter-continental travel time, thereby propelling the aviation industry into stratosphere and increasing the global financial throughput as a result of decreased flying duration -- in the next decade or so.
[0] https://www.tapatalk.com/groups/concordesst/concorde-s-envir...
Bringing our carbon footprint into the stratosphere as well (both via passenger miles, and via carbon per passenger mile).
And the chances for electrification are even more remote than for subsonic planes -- at least its conceivable that electric propeller planes could work, in 50 years or so.
And the chances for electrification are even more remote than for subsonic planes -- at least its conceivable that electric propeller planes could work, in 50 years or so.
How about hybrid propulsion systems?
I agree with your assertion that complete electrification of the aviation industry is several decades away, but a hybrid solution should be optimally feasible given the advances in battery density and related industries. [0]
[0] http://www.eenewseurope.com/news/hybrid-electric-aircraft-ne...
I agree with your assertion that complete electrification of the aviation industry is several decades away, but a hybrid solution should be optimally feasible given the advances in battery density and related industries. [0]
[0] http://www.eenewseurope.com/news/hybrid-electric-aircraft-ne...
I think battery for commercial jet airliners might be a long way off, due to jet fuel's energy density. Small planes might manage.
One idea I recall from Virgin Airlines a while back was to have planes towed around the airport so they didn't have to burn fuel on the ground. Ah here we go (2006!) :
http://news.bbc.co.uk/1/hi/business/6203636.stm
One idea I recall from Virgin Airlines a while back was to have planes towed around the airport so they didn't have to burn fuel on the ground. Ah here we go (2006!) :
http://news.bbc.co.uk/1/hi/business/6203636.stm
I guess we'll end up creating fuel on the ground with renewable energy and use that for jets. This would go a long way towards reducing emissions and only needs minor adjustments to planes/engines. I believe some airlines already tested alt fuel sources as a mix (although they were based on plant oil iirc).
Hybrids are stepping stones along the way to full electrification. They reduce emissions somewhat. We may see hybrids be commercialized for small planes in 10 years, for large planes in 20 years. etc. etc.
What I'm saying is that I don't see these technologies allowing supersonic speeds, meaning supersonic=fossil.
What I'm saying is that I don't see these technologies allowing supersonic speeds, meaning supersonic=fossil.
Am I understanding correctly that in the tests not the actual prototype will fly, but rather F/A-18s that somehow mimic the wave patterns generated by the X-59?
How does that work?
Complete guess but they might use multiple F/A-18s, each with their own boom in a specific formation, to mimic the non-combining booms of the X-59?
I'm curious to hear that, hopefully someone will record the attempts!
Please capitalize NASA -- it's an acronym (for National Aeronautics and Space Administration)
https://en.wikipedia.org/wiki/Magnetohydrodynamics
But yeah, it's a breakthrough...
Oh look https://en.wikipedia.org/wiki/Magnetohydrodynamic_drive
No one mentions as well that the optimum form factor for such a technology consists in two round plates facing each other (wink-wink).
But yeah, it's a breakthrough...
Oh look https://en.wikipedia.org/wiki/Magnetohydrodynamic_drive
No one mentions as well that the optimum form factor for such a technology consists in two round plates facing each other (wink-wink).
Hey! Hey! I live in Galveston.
I didn't know there was a citizen-scientist branch of this operation. (NASA did announce their plans earlier this year.) I'm actually quite excited about this happening.
I didn't know there was a citizen-scientist branch of this operation. (NASA did announce their plans earlier this year.) I'm actually quite excited about this happening.
There is an episode of the excellent Inside Skunkworks podcast about the Lockheed team that is building the aircraft for these tests:
https://soundcloud.com/user-291478498
It's well worth a listen, as are the other episodes in the series.
https://soundcloud.com/user-291478498
It's well worth a listen, as are the other episodes in the series.
"A low rumble" I presume? Thanks for the recommendation
I wonder if this is related to Boeing’s announcement: https://www.boeing.com/features/2018/06/hypersonic-concept-v...
It's weird to see real innovation happen again. For so many years innovation has been about how to fit as many meat bags as possible in a shoe box, prentending to be luxurious, at the adequate speed to save the most fuel as possible.
> innovation has been about how to fit as many meat bags as possible in a shoe box
That's an odd way to describe the most accessible era of global travel in human history. It's not like first class tickets, which provide a comparable experience at a comparable inflated-adjusted price, aren't available to bring back the 60s.
There are more travelers who want a cheaper ticket than there are those who want, more than cheaper tickets, (a) more comfort or (b) faster travel. Evidence for this is in the demand for cheap tickets with long layovers and repeat flyers in basic economy.
That's an odd way to describe the most accessible era of global travel in human history. It's not like first class tickets, which provide a comparable experience at a comparable inflated-adjusted price, aren't available to bring back the 60s.
There are more travelers who want a cheaper ticket than there are those who want, more than cheaper tickets, (a) more comfort or (b) faster travel. Evidence for this is in the demand for cheap tickets with long layovers and repeat flyers in basic economy.
I recently paid bottom dollar for a flight and was annoyed when my knees jammed up against the seat in front of me. I had to contort myself a bit to fit.
Then I chuckled at the annoyance since I, myself, had decided to get the dirt-cheapest flight available. Couldn't even be bothered to pay +$15 for an emergency exit seat.
...And I would've done it all the same again for that 2 hour flight.
I just saw a Reddit thread where someone asked how many people would pay extra for a flight with no babies allowed. I had to roll my eyes at every commenter who said they would.
Then I chuckled at the annoyance since I, myself, had decided to get the dirt-cheapest flight available. Couldn't even be bothered to pay +$15 for an emergency exit seat.
...And I would've done it all the same again for that 2 hour flight.
I just saw a Reddit thread where someone asked how many people would pay extra for a flight with no babies allowed. I had to roll my eyes at every commenter who said they would.
I regularly pay extra for a flight with no babies.
There are two airports an equal distance from my house. One has cheap flights, and the other does not. The one with the cheap flights also happens to be the airport for Walt Disney World.
I fly out of the expensive airport whenever possible.
There are two airports an equal distance from my house. One has cheap flights, and the other does not. The one with the cheap flights also happens to be the airport for Walt Disney World.
I fly out of the expensive airport whenever possible.
2 hour flight is OK, but 5+? I would pay up.
> Flying is the worst one because people come back from flights and they're telling you their story, and it's like a horror story. They act like their flight was a cattle car in the 40s in Germany. They're like, 'it was the worst day of my life! First of all, we didn't board for like 20 minutes and then they made us sit there on the runway for 40 minutes! We had to sit there!' Oh really? What happened next? Did you FLY in the AIR incredibly like a BIRD? Did you partake in the miracle of human flight, you non-contributing zero?! ... You're sitting in a chair in the SKY! Here's the thing: people say there's delays. Delays? Really? New York to California in 5 hours. That used to take 30 years! And a bunch of you would die on the way there, and have babies... you'd be a whole different group of people by the time you got there. Now, you watch a movie, you take a dump, and you're home!
— Louis CK
— Louis CK
I pay extra for direct flights and take JetBlue or Alaska Air when they're available regardless of the cost compared to other airlines like United. I rarely come across babies on my flights, but I'd pay a bit more for an airline that resulted in reduced boarding and deplaning times.
> It's not like first class tickets, which provide a comparable experience at a comparable inflated-adjusted price, aren't available to bring back the 60s.
A Business Class ticket on an international route is incomparably luxurious compared to anything you could purchase in the 1960s. And some of the First Class products take it to the next level. That's before you take into account the safety, time-saving, and cabin-pressure differences.
A Business Class ticket on an international route is incomparably luxurious compared to anything you could purchase in the 1960s. And some of the First Class products take it to the next level. That's before you take into account the safety, time-saving, and cabin-pressure differences.
Part of that is improvements in HPC. You can now do computational analysis of these designs and evolve a good solution way faster than was done by hand in wind tunnels for the Concorde and other supersonic aircraft. I don't think this would be possible without today's computational technologies, which allow orders of magnitude more "experimentation" (even if virtual) and therefore iteration in design.
Aside: personally I'm waiting for someone to take up the Avrocar, aka the original flying saucer UFO. It's basically the jet version of the helicopter or quadricopter drone from an aero engineering tradeoff standpoint. At one point the Army thought that they'd stop buying jeeps and start buying flying saucers instead, but the Avrocar project fell apart for dynamical stability reasons. It was just too difficult to keep it in level flight during flying regime transitions, and they weren't able to design a control interface a human could use to compensate. But that was with 50's tech, and I'm pretty sure with modern ML techniques you could design a fly-by-wire feedback response control system that would have no trouble stabilizing Avrocar or an improved version of it, just like Stanford got a helicopter to fly upside down (a very analogous stability regime actually). It would fill the niche for medium-distance drone transport or perhaps short-range personnel transport (like choppers).
Aside: personally I'm waiting for someone to take up the Avrocar, aka the original flying saucer UFO. It's basically the jet version of the helicopter or quadricopter drone from an aero engineering tradeoff standpoint. At one point the Army thought that they'd stop buying jeeps and start buying flying saucers instead, but the Avrocar project fell apart for dynamical stability reasons. It was just too difficult to keep it in level flight during flying regime transitions, and they weren't able to design a control interface a human could use to compensate. But that was with 50's tech, and I'm pretty sure with modern ML techniques you could design a fly-by-wire feedback response control system that would have no trouble stabilizing Avrocar or an improved version of it, just like Stanford got a helicopter to fly upside down (a very analogous stability regime actually). It would fill the niche for medium-distance drone transport or perhaps short-range personnel transport (like choppers).
Do you even need ML for the flight control? I have no experience designing anything remotely related to aircraft software, but from a distance it seems that the big thing would be making micro-corrections to stabilize the flight. I don't think you need ML just for that.
No, but that’s how Stanford pulled off the inverted helicopter trick. Point is that flying regime is too difficult to design by hand, but ML is powerful enough to design a controller for us.
It's crazy to think that in 2016 there were ~3.6 billion airline passengers. Passenger airplanes started as a luxury and moved to mass market. Honestly, humanity benefits more from having high capacity cheap flights than having lower capacity more expensive faster flights. Luxury options aren't off the table, buy business class or go private.
And saving fuel is in everyone's best interest.
And saving fuel is in everyone's best interest.
> saving fuel is in everyone's best interest
> started as a luxury and moved to mass market
These two objectives are contradictory. There are so many more trips because the fares are cheap, so fuel consumption is much increased.
> started as a luxury and moved to mass market
These two objectives are contradictory. There are so many more trips because the fares are cheap, so fuel consumption is much increased.
Surprisingly, if you're alone and the alternative is driving a personal vehicle, flying may be the more efficient way to get to your destination (but the comparison is inherently difficult).
(Of course, I don't doubt that a lot of trips happen today which wouldn't have happened in the 60's, so you're probably still correct.)
https://www.yaleclimateconnections.org/2015/09/evolving-clim...
(Of course, I don't doubt that a lot of trips happen today which wouldn't have happened in the 60's, so you're probably still correct.)
https://www.yaleclimateconnections.org/2015/09/evolving-clim...
> Japan Airlines invested $10 million into Boom Technologies,
OK so Boom has raised 47.3M so far according to techcrunch which is ... nothing? Even something as relatively simple as the Sukhoi Superjet 100 had a program cost of 1.5B. I can't even imagine how much a supersonic jet will cost.
OK so Boom has raised 47.3M so far according to techcrunch which is ... nothing? Even something as relatively simple as the Sukhoi Superjet 100 had a program cost of 1.5B. I can't even imagine how much a supersonic jet will cost.
I don't think anyone in aerospace expects Boom / Aerion / Spike etc to actually deliver. More likely they're positioning for acquihire.
Probably Boom only delivers at this point CAD drawings and scale-models. They get some limited wind tunnel time to test their models. Probably if they can show they have something, they will partner with an manufacturer (Airbus? Saab?) to build a prototype.
There are Boom engineers lurking around HN, probably one of them can pitch in and comment.
There are Boom engineers lurking around HN, probably one of them can pitch in and comment.
So the F-104 Starfighter tests in Oklahoma in 1964 were not good enough then?
https://en.wikipedia.org/wiki/Oklahoma_City_sonic_boom_tests
It seems that the military have more money than sense to pursue a failed idea that isn't going to help win The War Against CO2 levels. Only in America.
https://en.wikipedia.org/wiki/Oklahoma_City_sonic_boom_tests
It seems that the military have more money than sense to pursue a failed idea that isn't going to help win The War Against CO2 levels. Only in America.
Good enough for what? This is about aircraft design to reduce/eliminate the booms. Those test were about finding what the public would put up with, that being none at all.
In a bid to save America's transatlantic and transpacific airline industry, the US banned the Concorde from flying over the mainland because of "noise concerns".
I feel like Europe should return the favor should this ever result in an airliner.
I feel like Europe should return the favor should this ever result in an airliner.
Wtf? The noise concerns were legitimate, and started in the UK, not America. Know your history:
https://en.wikipedia.org/wiki/Anti-Concorde_Project
https://en.wikipedia.org/wiki/Anti-Concorde_Project
DocTomoe(4)
Noise “concerns” were very much genuine with the Concorde.
An incredible achievement of technology and engineering, but an environmental disaster.
An incredible achievement of technology and engineering, but an environmental disaster.
The Russian Tu-144 knockoff was even worse. I've seen the passenger experience memorably described as "so loud you couldn't hear the person next to you screaming".
I couldn't resist learning more about this.
> Passengers seated next to each other could have a conversation only with difficulty, and those seated two seats apart could not hear each other even when screaming and had to pass hand-written notes instead. Noise in the back of the aircraft was unbearable. Alexei Tupolev acknowledged the problem to foreign passengers and promised to fix it, but never had the means to do so.
https://en.m.wikipedia.org/wiki/Tupolev_Tu-144
> Passengers seated next to each other could have a conversation only with difficulty, and those seated two seats apart could not hear each other even when screaming and had to pass hand-written notes instead. Noise in the back of the aircraft was unbearable. Alexei Tupolev acknowledged the problem to foreign passengers and promised to fix it, but never had the means to do so.
https://en.m.wikipedia.org/wiki/Tupolev_Tu-144
What about all the military aircraft?
Military aircraft are highly restricted from going supersonic over populated areas too[0].
We live near a US Air Force base, we had a single sonic boom last year and the base put out a tweet/statement apologizing, and the pilot got written up.
During national security incidents like 9/11 all bets are off.
[0] https://aviation.stackexchange.com/questions/44759/do-usaf-f...
We live near a US Air Force base, we had a single sonic boom last year and the base put out a tweet/statement apologizing, and the pilot got written up.
During national security incidents like 9/11 all bets are off.
[0] https://aviation.stackexchange.com/questions/44759/do-usaf-f...
When I was a kid in the 60s, sonic booms were regular from the AF. I always enjoyed them.
Most countries have restrictions on when/where military planes are allowed to fly supersonic. If they have to cross the sound barrier over populated area (happened over southern Germany last year), this always causes a lot of publicity and can even result in shattered windows (which the military will pay for).