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NASA Has a Way to Cut Your Flight Time in Half (bloomberg.com)
An anonymous reader shares a Bloomberg Businessweek article: For almost a half-century there's been a clear speed limit on most commercial air travel: 660 miles per hour, the rate at which a typical-size plane traveling at 30,000 feet breaks the sound barrier and creates a 30-mile-wide, continuous sonic boom. That may be changing. In August, NASA says, it will begin taking bids for construction of a demo model of a plane able to reduce the sonic boom to something like the hum you'd hear inside a Mercedes-Benz on the interstate. The agency's researchers say their design, a smaller-scale model of which was successfully tested in a wind tunnel at the end of June, should cut the six-hour flight time from New York to Los Angeles in half. NASA proposes spending $390 million over five years to build the demo plane and test it over populated areas. The first year of funding is included in President Trump's 2018 budget proposal. Over the next decade, growth in air transportation and distances flown "will drive the demand for broadly available faster air travel," says Peter Coen, project manager for NASA's commercial supersonic research team. "That's going to make it possible for companies to offer competitive products in the future." NASA plans to share the technology resulting from the tests with U.S. plane makers, meaning a head start for the likes of Lockheed Martin, General Dynamics, Boeing, and startups such as Boom Technology and billionaire Robert Bass's Aerion. [...] NASA is targeting a sound level of 60 to 65 A-weighted decibels (dBa), Coen says. That's about as loud as that luxury car on the highway or the background conversation in a busy restaurant. Iosifidis says that Lockheed's research shows the design can maintain that sound level at commercial size and his team's planned demo will be 94 feet long, have room for one pilot, fly as high as 55,000 feet, and run on one of the twin General Electric engines that power Boeing Co.'s F/A-18 fighter jet.
We were told that the Concorde was not commercially viable even when tickets were 5-10x the price of coach for the same route. What will this new design do to put the tickets into a price range that more consumers can justify paying? Otherwise we already have ways to hold meetings in France in the AM and make it to NYC in time for dinner, it's called videoconferencing.
Damn_registrars has no butt-hole. Damn_registrars has no use for a butt-hole.
Did I miss a link or does TFA have absolutely no information on how they actually reduce the sonic boom signature?
News for nerds, right? Where is the nerd part?!
But.. the fuel cost is really high and when the oil price shot through the roof, there is no way commercial super sonic transport could become a success. Supersonic transports are coming back, this time as small 20 seater or smaller targeting the super rich. There was an Airbus concept a couple of years ago. Now an American trial balloon.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
I'd rather have a cheaper flight.
Or a more comfortable flight.
Or a more private flight (fewer passengers sat on top of me).
A quicker flight is very low on my list of priorities. Flights are already pretty fast.
"That's the way to do it" - Punch
We need to get the government out of the business of doing basic research for corporations. "Gubment handouts BAD!", remember? If the airlines and Boeing et al. want to do this, they can do it on their own in their precious precious sacred free market, without government gravy-train taxpayer handouts.
I'm pretty sure I don't want busy restaurant background level noise going on continuously. That would suck. I don't even want quiet restaurant background noise going on continuously.
And I'm an American, but isn't it really time we started using metric for all things tech? Thirty miles is about 50km. It's just not that hard.
From the time to travel to the airport, have a cavity search, get your tits and ass measured, and clothes back on.. 2 hours. In fllight...3 hours. Arrival, bag handling, taxi, 1 hour.
Life is not for the lazy.
That quote was from Negroponte in the time of Wired: https://en.wikipedia.org/wiki/...
Air travel is noise polluting, air polluting and fossil fuel driven. Half the time, with network improvements, we can make do with teleconferences. In fact, working in Brussels in the 1980s, we already used teleconference to save trips to the computer centre in Luxembourg.
I'm not saying that we stop air travel, I enjoy my holiday too, but we really need to minimise and substitute. I take the the high speed train (TGV) from Paris to Marseilles now, it's 4 hours, probably less than the flight once I've dealt with two internal airports. So, whilst this is interesting research, it should a be white elephant in a greener, quieter, less polluted world.
On y va, qui mal y pense!
NASA and the government in general is nothing but a bunch of wasteful bureaucrats, taxes are theft and anything that doesn't pay dividends this week or next is prime for downsizing.
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I can't wait to see the size of these new mufflers.
I'm pretty sure I don't want busy restaurant background level noise going on continuously.
I prefer to think of it as a constant thunderstorm, since that's probably closer to what it'd be like - a series of double-booms at various intensities (depending on the distance of the aircraft).
And I'm an American, but isn't it really time we started using metric for all things tech? Thirty miles is about 50km. It's just not that hard.
Tell that to a non American who never learned dimensional analysis more complicated than moving a decimal point. The fact is that some non-SI units are still commonplace globally; the calorie being the big one that comes to mind.
I agree it's antiquated and quaint to continue to use imperial units, but having to do something _other_ than shift a decimal point around is very useful in teaching dimensional analysis.
-- Sometimes you have to turn the lights off in order to see.
I'm also curious how much more fuel this uses than subsonic commercial airliners.
As a general rule of thumb, fuel consumption goes up as the square of the speed. Double the speed, and you quadruple the fuel consumption.
But there are a lot of other considerations. For instance, faster planes can fly higher, where air density is much lower, and jet engines can be designed to work better at high speeds and high altitudes, but with the tradeoff that they work worse during the low speed take-off and landing.
On the other side, big planes are much more efficient per passenger-mile than small planes. The Concorde had a narrow body, and just couldn't carry enough passengers to make it cost effective. But it is questionable if there is really a mass market for fast and expensive air travel. Would you pay an extra $2000 to shave 3 hours off a trans-Atlantic flight? I certainly would not. I'll just download an extra book to my Kindle.
Continuously? Unless you're traveling at the same speed across the ground in the same direction, it won't be continuously. It's a wave - it moves past you.
Doubling speed = 4x fuel cost. My RT flights to India typically costs about $1500, and according to the fine summary BA shows me, that's about $600 for the flight itself, and $800+ in taxes and (government) fees.
So what part of that $600 is for fuel?
Your guess is as good as mine. I'll guess it's half, i.e. $300. Thus 4x or $1200 would be the fuel cost, same $300 for all the other costs, and the same $800 in taxes and fees.
Result: $2300 to fly at mach 1.7 (2x a typical 757/767/777/787/A380, which flies at mach .85). Sounds good to me. That wouldn't break the bank where I work and I could get there in ten hours instead of twenty. Of course it probably wouldn't really end up being ten hours, maybe more like twelve or thirteen. Still, I'd consider that a win.
The sonic boom is not really an issue. The actual sonic boom from Concorde at cruise altitude...posed no real risk.
No, the sonic boom really was a serious issue and was the reason why Concorde was limited to flying to the eastern seaboard of the US. It was not that it was dangerous but more the noise which you can hear in in this video around the 1 minute mark from a plane claimed to be at 50-60,000 feet. It is certainly not negligible and you would not want to be hearing that multiple times a day if you were living under a flight path.
The take-off noise is also not negligible. As a grad student, I remember waiting on a plane to take off at Heathrow one evening when there was a deep-throated roar, the plane vibrated slightly and Concorde shot down the runway next to us with blue flames shooting out of its afterburners. It was a heck of an impressive sight but not exactly a quiet one! While fuel costs are certainly an effect when they were shutting down the Concorde program one expert commented that a plane designed today would be hugely more efficient but that the fact it would still make a sonic boom would limit it to so few routes the market would be too small to make it financially viable. If NASA can fix this then it could well cause a renaissance in supersonic flight.
There is no such thing as 12am or 12pm. ante meridiem or post meridiem – before the meridiem, i.e. noon, or after it. 12 o'clock is either 12 noon, or 12 midnight. I put idjits that write 12am right up there with the ones that can't figure out your, you're, there, their, and they're.
having grown up in a country that's been metric for over 200 years.
So France.
If I only have to cram myself into a tiny seat and sit there with blood flow below my knees cut off by pressure from the seat in front for 4 hours instead of 8 hours I'd call that a more comfortable flight.
I recently took a ~4 hour flight, and spent almost 6 in the airport tween TSA sloths, the cattle car of an airplane being loaded, delays on the runway, getting my luggage at baggage claim, and waiting for a fucking bus to go to the car rental place
Then to top it off, it doesnt matter how early or late my flight is, or where I am going, I always get there at either morning or afternoon rush hour
There's usually more than one plane flying overhead within a 50km radius. I don't need to follow one plane to be bothered by its sonic booms.
Sure, cutting flight times are nice but for most travelers the longest part of the trip is getting through airport security. Faster airplanes won't fix this, but it will make that time stick out more to the consumer.
If the TSA still insists on people arriving 2 hours in advance for a 5 hour flight instead of a 10 hour flight then people are going to notice that wait time more.
For many people the flight time could be cut in half by just doing a proper security check instead of this over the top crap the TSA has been doing.
I am armed because I am free. I am free because I am armed.
I agree it's antiquated and quaint to continue to use imperial units, but having to do something _other_ than shift a decimal point around is very useful in teaching dimensional analysis.
It's worse than you realize because the American's don't use Imperial units, they use the same units with different definitions. If you order a pint of beer in the US you will be sorely disappointed. It is only about 80% of a UK pint because they have a different number of fluid ounces in a pint and a (slightly) different definition of a fluid ounce. If this is not bad enough for dimensional analysis on top of this Imperial units use pounds for both mass and force resulting in further confusion.
Technically I believe a pound is supposed to be force and the slug is the Imperial/US unit of mass but mention 'slug' to someone in the US and they will think you are talking about gardening problems, not units of mass. The US physics textbooks which we also get up here in Canada talk about "pound-force" and "pound-mass" so the dimensions of just a pound is somewhat ambiguous e.g. I have seen density in 'lb/ft^3' and pressure as "lb/in^2" where one is used as a mass and the other as a force! Using Imperial/US units for anything serious is a terrible idea. The Imperial and US unit systems are inconsistent and ill-defined which makes them absolutely terrible for doing dimensional analysis let alone teaching it!
Fuel cost is a lot less than that. For example, only 15% of American Airlines current operating expenses are fuel. Here are the figures for anyone who is interested:
http://www.aviationdb.com/Aviation/FuelExpenseByCarrier.shtm
So now the portion of my travel time taken up by TSA is even greater? Fuck that, I'll take a train.
I'm not sure how reliable the "NATS" site is (http://www.nats.aero/environment/aircraft-noise/) but according to that page, aircraft at cruise altitude appear to come in around 40 dBA. This NASA target is 60-65 dBA... more than 50% higher than the people-movers of today. As someone who lives under the ingress/egress route of a local airport, this seems like an egregious increase in ambient noise. Huge fan of halving flight time but not at the expensive of my auditory sanity!
An interesting fact mentioned is the use of the engine from an F-18. Fighter jet engines aren't very fuel efficient, they are fast. (Not an aeronautical engineer, but) I have read that the reason commercial jet engines are so large is because they are fan jets. They suck in a huge amount of air and bypass the main engine. The more air you suck through the main engine, the more fuel you can burn and you go faster. The large bypass allows slow jet planes to cruise along at 500mph while sipping gas.
So with all that in mind, is the barrier to selling a lot of supersonic jet tickets really the sonic booms? The Concorde didn't go under because it was annoying too many transatlantic tanker crews with sonic booms. I may not be fully informed, but this seems like a dumb business plan if you are just trying to solve the audio problem.
An interesting alternative: It is NASA, they do work with the military on occasion. Perhaps this is a research project that can apply to supersonic military aircraft in an effort to make them more stealthy. If you are invisible to radar, but everybody hears you once you punch the throttle, you have wasted a lot of green on stealth technology. So, for maximum stealth, you need to fly slow. This type of tech would solve that, and I can see the military spending hundreds of million on R&D to solve that problem.
An F-18 engine is exactly the sort of engine I would test with if I planned on introducing this technology to next generation military aircraft.
HA! I just wasted some of your bandwidth with a frivolous sig!
As the gap between the rich and poor expands, there will be a market for the faster air travel, you might not call it a mass market, but I've met people who have a Cessna Citation for speed plus a Gulfstrem when they're not in a hurry - these guys would certainly add a 1200+mph jet to their fleet if they could use it over land routes.
You're not just paying for fuel, you're also paying for maintenance, staffing, ground facilities, national security, baggage handlers unions, etc.
As you point out, ground "time costs" run 2-3 hours per flight, minimum, so to make the reduction in flight time worthwhile, it needs to be a 5+ hour flight to begin with, otherwise you won't notice the advantage except in the ticket price, and perhaps the awful delays when your super-jet has mechanical problems delaying takeoff (without a whole fleet of fungible replacements at the ready.)
As they said: NY-LA, interesting. NY-DC, not so much.
In this video by Wendover Productions on why the Concorde failed, they mention the economics of commercial flight. Sonic booms aren't the problem. Long story short, flying time doesn't matter as much as ticket revenue and fuel cost. If an airplane consumes more fuel flying faster than the speed of sound than slower, and people aren't willing to pay for the increase in cost, then airlines won't fly faster.
For instance, faster planes can fly higher, where air density is much lower, and jet engines can be designed to work better at high speeds and high altitudes, but with the tradeoff that they work worse during the low speed take-off and landing.
I'm not an aerospace engineer, so forgive me for asking a probably stupid question, but would it be possible to build the jets with two sets of engines - one efficient for landing and takeoff, the other efficient for cruising at altitude?
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What does it hum, Deutschland Uber Alles?
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
I wanted to say: I believe it when I don't hear it.
I spend half an hour or more driving to the airport, five to fifty minutes waiting to check a stupid bag (you can eliminate this time by flying pretty much naked), and then anywhere from fifteen to forty five minutes waiting for security. Then I have to wait for a train to get to a gate (smaller airports don't have this problem, and even some bigger ones let you walk, but not the ones I am usually at), and take said train, then get to the gate, another minimum twenty minutes and usually closer to thirty.
At that point, you could teleport me to my destination, and as long as I still have to wait for a dumb machine to spit my bag out, then wait for a van to go to rental, and then wait in line at Avis Preferred booth to figure out why their system of directing me directly to my car failed yet again and they have to punch shit into my computer- and it would still be a pain in the ass.
If I take a four hour flight, I have at least two, and sometimes four hours of drama pre-flight, and around one afterwords. The actual time flying is the most pleasant part of the trip, because I can pass the fuck out. I just need a seat that is not scientifically designed to be totally bullshit, and to not have a bunch of security theater, which represents real risk when they decide to rifle through my belongings for a prolonged period of time.
Not just weight, drag too. Any engine not producing thrust is still producing drag.
So yes, you could do this, but it would be more efficient in the long run to just forget the less powerful set of engines.
...when the sound of a turbojet-engined airliner taking off was deafening. Today's turbofans whisper in comparison. People are willing to put up with a certain amount of noise pollution if there's a big enough payoff.
Drill baby drill - on Mars
Per their Wikipedia pages, a G650 at normal cruise is a tiny fraction slower than a Citation X, and even at long-range cruise is only about 10% slower, but it has over twice the total range of the Citation. Am I missing something here? Seems like the difference is tiny and more than made up for by the massive range increase - not having to stop to refuel helps immensely.
I'm not an aerospace engineer, so forgive me for asking a probably stupid question, but would it be possible to build the jets with two sets of engines - one efficient for landing and takeoff, the other efficient for cruising at altitude?
That was the whole point of Concorde's Engines - they could be used for takeoff/landing but would sustain Mach 2 cruise WITHOUT afterburners or reheat. They were only used for takeoff and to get through the sound barrier quickly. The clever bit was the variable ramp intake doors at the front of the engine controlled by an analogue computer - a real engineering achievement. I'm still amazed that you could sit at Mach 2 and 60,000 ft sipping champagne whilst anyone else was wearing an oxygen mask and peeing in a tube,
Theres no point - you would get much better efficiency gains if you could optimise the wing for both climb and cruise, rather than one or the other.
That's why Musk and his Hyperloop are targeting the short runs, like NY-> DC or SEA -> PDX. Different tools for different jobs. If they'd share infrastructure, though, that might make things easier.
An interesting claim, what makes you think that? I'd have thought everyone who has designed long-haul fast aircraft has made the same calculation and they seem to have come up with an efficient high speed wing, and then added bodges to make it suitable for low speed.
The fact that Airbus used to optimise its wings for the non-cruise periods rather than the cruise - because it was worth it. They didn't really switch until they introduced the A340-500/600 aircraft, and the A380 initial wing was leaning toward the non-cruise optimisation as well until they introduced a twist into later models and shifted the optimisation to the cruise phase. Boeing has always optimised for cruise in its wing philosophy.
Planes spend enough time at lower altitudes that you do have to make concessions to optimise for it - when you start getting into the fuel use with flaps and slats extended, it especially starts to make sense at a certain point.
Optimisations at low altitude have a larger pay off than optimisations at higher altitudes - theres more induced drag because the airs thicker.
Let people arrive 30 minutes before the flight, and get them out within 15 minutes within landing. Nothing more than snail pace speed require, no supersonic NASA stuff.
Would you pay an extra $2000 to shave 3 hours off a trans-Atlantic flight?
Maybe not a trans-Atlantic flight, although I know many people that travel that route for business that would for sure.
I live in the UK and my family is in Australia. It is a 32+ hour trip, with something like 22 hours in the air (friend of mine just did Melbourne to Cambridge and it's a 39 hour trip).
Halving the flight time means I can go see my family more often. I would cheerfully pay twice as much to cut 10-12 hours off the flight time. The cost of flying home for me is not prohibitive but the time - both in terms of the sheer flight time and also the recovery time for spending so long in the air, which seems to get longer the older I get) - most definitely is.
That calculation isn't as simple as you might think. Airlines buy fuel futures to be able to predict their costs and often over-buy incase they add more routes. They then trade these. If the fuel cost goes up a lot, then selling the futures can be quite profitable, and in a few cases completely cover their cost of buying fuel, so that 15% may include the cost of fuel minus a big profit when they sold some futures to another airline.
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LHR to SFO, SFO or LHR to NRT would benefit from shorter flight times. LHR to JFK is barely worth it because so much of the total travel time is getting to and from the airports and time spent hanging around the airport in the slack that you had to allow in case of delays or really long security lines.
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According to this the fuel cost is about 3% on a short haul flight. Even if it's 6% on long haul, that would be $90.
const int one = 65536; (Silvermoon, Texture.cs)
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As a general rule of thumb, fuel consumption goes up as the square of the speed. Double the speed, and you quadruple the fuel consumption.
Are you sure that rule of thumb applies past the sonic barrier? Because supersonic aerodynamics are quite different than subsonic, IIRC (which is why simulations like to use fluids to simulate supersonic aerodynamics).
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the TSA?
There's no time like the present. Well, the past used to be.
First read title as: "NASA has a way to cut your fingers in half time" .. wait .. what? *reading again* aaaah...