NASA Has a Way to Cut Your Flight Time in Half (bloomberg.com) 234
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.
No mention of ticket prices (Score:5, Insightful)
Re:No mention of ticket prices (Score:5, Informative)
Part of the reason it wasn't commercially viable was that it had limited route availablility -- it could not go supersonic over CONUS, so was limited to JFK-LHR and JFK-CDG. If the sonic boom is reduced to non-invasive levels, then suddenly more routes become feasible... LAX-, ORD-, SFO- etc...
Also, engine technology has improved quite a bit since the Concorde was designed.
Re:No mention of ticket prices (Score:5, Informative)
Engine technology has improved for subsonic aircraft. You can't make a high-bypass geared turbofan go supersonic. It just isn't designed for that. It'll tear itself apart if it doesn't first choke on it's own shockwave. Modern engines are designed to cruise at 500 miles per hour while sipping as little fuel as mechanically possible.
The only commercially available engine we have right now for going supersonic is the JT8D design and it's derivatives ... and the core ideals of that design is pushing 50 years old at this point. JT8Ds are loud dirty gas guzzlers whose usage is forbidden at pretty much every major U.S. and European airport specifically because it's so loud and dirty.
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Well, yeah, because there wasn't a market for commercial supersonic engines before this. Of course all the development went into subsonic ones! If NASA makes a plane that can go supersonic quietly, the engine development will follow, as there will be money in it.
Re:No mention of ticket prices (Score:4, Insightful)
That's a hell of a chicken-or-egg problem
That's why a government is involved in solving the problem. Governments can spend a lot of money in situations where the private sector will not, due to the long ROI.
If NASA can get a quiet supersonic passenger aircraft body, that solves the chicken and egg problem. They at the end may need a better engine to make it economically viable, but private industry would have something to hang those engine(s) on.
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Gee, you don't think that might be why they are using a fighter jet engine on their demonstrator hardware, do you?
Use what you have available to validate the design and concept, and create the market that gets the aerospace firms working on the better supersonic-capable engines.
Now where do you think that NASA could get their hands on some fighter jet engines...
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Engine and Aerodynamic improvements do not change the real limiting factor: cost.
The average consumer can look at it and figure out if the opportunity cost of the time saved is worth the increased ticket price. So far, the answer has been "no."
It's certainly possible for the increased fuel burn of supersonic flight to be offset by the shorter flight time; the XB-70 Valkyrie is a great example of that.
That said, the XB-70 was worth more than its weight in Gold, and was plagued with an extremely expensive ins
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The XB-70 also lost out to ICBMs. The whole point of the Valkyrie was to speed past Soviet air defenses (or possibly stay out of range--dropping from 70,000 feet at a decent speed gets you a good range even on a dumb bomb). If ICBMs hadn't worked out, the Valkyrie (or some variant of it) might have had a chance. As it was, the Defense Department largely ended development of large, high-speed aircraft.
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There were initial preliminary design studies for a Mach-3 bomber, and they eventually lead to the Valkyrie... but it never really 'competed' against ICBM's -- that decision was final about a year before the contract for the XB-70 was awarded to North American.
The actual contract for the XB-70 was for a pure research platform, much like the X-1, the Douglas Skyrocket, or X-29. Flying into enemy territory, even as a recon plane was off the menu - it was too expensive, and too easy to shoot down.
The Valkyrie
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Sonic boom wasn't the biggest problem. Concorde was measured at takeoff and landing at over 126 dB in 26 of 37 monitored tests [nytimes.com], which is twice the permitted/advertised limit of 110 dB.
For a quick comparison, that makes Concorde four times louder than a 747 at takeoff.
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The other restriction was Concorde's limited range. If it had been designed for transpacific routes the over-ocean limitation wouldn't have been so bad. Cutting by more than half the 11 hour West Coast to Tokyo, or
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I think the point of this exercise is to create a mode of travel for people that the saying "time is money" applies to the most, but have the average Joe pay for the R&D through taxes. That's how seems on the surface anyway.
"Your taxes paying for something you will not be able to afford to use! Aren't you glad you gave us the purse strings? Thanks!"
Re:No mention of ticket prices (Score:5, Funny)
Because nothing the rich have ever make to the average Joe. Now, if you'll excuse me while I use my cell phone telephone to call my mom upstairs to get in her car to buy me a big screen plasma TV.
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Note that none of those things have ever required amounts of energy to operate that the average Joe couldn't afford.
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o.O
Which average Joe would pay $5000 for a cell phone telephone [timetoast.com]
Or $15000 for big screen TV [techwalla.com]
How many people in 1885 could afford Karl Benz's car? They probably waited for the Model T in 1908 but missed out on the Model A. $800-$900. While affordable still very much a luxury item. [wikipedia.org]
Now, being in the basement is odd considering that we have double the size of an average Joe house [npr.org].
I honestly have absolutely no idea what you mean.
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Well, unless you mean my mom but she has always been affordable... ... ... She calls me her little business expense. =/
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I mean that technology prices come down but energy prices don't so much. An average Joe would have no trouble affording the energy to run that cell phone, big screen TV, or car when they were new. An average Joe couldn't afford their share of the energy needed to propel an aircraft to supersonic speeds when the Concorde was new, and still can't. Probably never will short of fusion energy and a Shipstone battery. That is what keeps supersonic flight out of the average Joe's hands.
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You are forgetting the insanely expensive satellite phones the size of a briefcase that went before the cell phone. Hell, one of the requirements for something to go from rich-only to luxury to commonplace is finding ways of mass-producing and lowering the price. That's the whole POINT and is exactly what happened with the 'modern' cell phone in the 80s and 90s.
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I think the point of this exercise is to create a mode of travel for people that the saying "time is money" applies to the most, but have the average Joe pay for the R&D through taxes
Tell me about it. People should stick to boats like they always have.
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People probably said the same thing about researching jet propulsion.
How'd that work out for everyone?
Re:No mention of ticket prices (Score:5, Insightful)
For most flights you can probably cut the travel time, by reducing the time you have waiting around at the airport.
For an 8 hour flight across the US.
You need to arrive an hour before takeoff to get thru security. The flight is often an hour late arriving, then it takes an hour to get clearance to lift off. Then there is a delay awaiting for permission to land.
For flying there is a lot of sitting around on the ground waiting.
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These jets won't get purchased by big airlines like American, Delta, and United... they'll get purchased by companies like NetJets.
NetJets customers don't stand in line to go through TSA security and deal with crowded airport terminals... they use general-aviation airports like FXE (Fort Lauderdale Executive Airport), so they can literally drive (or be driven) to the jet on the tarmac, park, board, and fly away (or land, disembark, get in the car, and drive away) without drama or ceremony.
Put another way, i
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And a lot of time at the arrivals end waiting for passport control and waiting for bag collection etc...
They should do the immigration on board the plane, visiting each passenger at their seat once the plane is in the air. Some ferries already do this, so when the boat reaches land you just get off immediately having already cleared immigration.
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The Concorde was too expensive to operate for all sorts of reasons.
It was designed before the world at large had enacted regulations against excessive noises over residential regions, as well as before the oil crisis of the '70s. By the time the first orders were being fulfilled in the late '70s, the general perception by the airlines was that it was a gas guzzler that was half as efficient as competing models while offering no competitive advantage along the vast majority of routes, due to its inability to
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Had Concorde seen more demand, there would have been gradual improvement in efficiency and noise over time... There was already a model b concorde designed with a longer range and lower fuel use, but due to only 20 planes being built never went into production.
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The problem isn't just that supersonic travel creates sonic booms that the public doesn't like. The problem is also that any new airplane has to be fuel efficient and economically viable to make the airlines interested. If we look at the difference between the Airbus 380 and the Boeing 787, it was two different approaches to economic viability. Airbus put more passengers in a plane while Boeing focuses on more fuel efficiency through lighter materials and better engines.
The 380 also bet on the hub-and-spoke
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A second problem was passenger capacity, which impacted ticket price. The Concorde only carries 100 people, while an Airbus carries over 800. If both cost the same to operate, yo
Re:Or fuel requirements (Score:5, Interesting)
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.
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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 ma
Re:Or fuel requirements (Score:5, Informative)
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 [aviationdb.com]
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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
Re: Or fuel requirements (Score:3)
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.
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Stealth Requirements? (Score:5, Interesting)
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.
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Military, private, and if Great Britain gets another nationalistic shot in the arm, they just might make a "new Concorde" applying the lessons learned from the last go around.
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The Concorde was blocked from flying popular routes across the US because "sonic booms will upset the cows and reduce milk production", and "sonic booms will destabilize the structural integrity of buildings/cities".
Restricting the usefulness of the Concorde to purely NYC-London and LA-Tokyo routes had a significant impact on it's profitability.
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I imagine that part of the Concorde problem was that it could only fly transatlantic, because the governmental regulatory bodies in various countries banned it from flying over populated areas, for good reason (sonic boom).
The more time a plane is in the air, the faster it pays for itself. The more of that model that are produced, the cheaper the per-unit cost. If you can only run back and forth between Heathrow and JFK twice a day, you don't need 100+ of that aircraft manufactured, and you jack up the ti
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This feels more like something that will be eventually sold to billionaires, people wealthy enough to own and operate their own $50-100 million aircraft. The noise regs meant that a billionaire couldn't do supersonic travel to most places even though he could afford the plane. Get the noise down and now those supersonic business jets can be built, sold and operated pretty much worldwide.
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The sonic-boom problem locked the Concorde out of most of the really long-haul runs: things like Europe-West Coast US, Asia-East Coast US, and Anywhere->Chicago/Atlanta. New
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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.
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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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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
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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.
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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.
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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 - b
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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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TWA, Continental, Pan Am, and United Airlines were each responsible for some of the largest purchase orders for the Concorde, so I'd hardly say it's reasonable to suggest they were "threatened" by the Concorde.
And it wasn't just the US that banned those flights. Much of Europe and Asia did as well, even countries that you may not expect to put such a high value on noise concerns (e.g. India and Malaysia both banned supersonic Concorde flights over their airspace).
The bigger problem, however, was simply that
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When the support contract ended, it wasn't just "prohibitively expensive" to continue operations, it was impossible - Airbus withdrew the manufacturers certificate, without which no one could fly Concorde commercially. It wasn't as simple as getting another entity to pick up the support contract.
So how does it work? (Score:2)
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?!
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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?!
Apparently it's just technology... https://en.wikipedia.org/wiki/... [wikipedia.org]
This Nasa/Lockheed deal was signed back in 2016...
Sonic boom was never a problem. Fuel cost was. (Score:3, Interesting)
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.
Sonic boom was definitely the problem (Score:5, Insightful)
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 [youtube.com] 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.
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Concord was loud taking off because it had 50 year old reheated turboramjet engines that were amazingly advanced for its day, but really shouldn't have been on a commercial airplane.
When it is the last time you flew on an airliner with afterburners?
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Concord was loud taking off because it had 50 year old reheated turboramjet engines that were amazingly advanced for its day, but really shouldn't have been on a commercial airplane.
When it is the last time you flew on an airliner with afterburners?
Yes and? Fast forward to now and the technology has done what exactly? It's not like any modern airliner engine technology is suitable for supersonic flight, and it's not like any of the planes capable of supersonic flight are any quieter now given they have no incentive to reduce their noise.
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And I remember sitting in my car in stationary traffic on the M25 just near Heathrow early one evening. It was dark, and suddenly my car started to shudder, as though it was thundering. And then I saw Concorde flying over, just taking off for its evening trip to NY. It had its burners on, and it looked like the Millenium Falcon, with bright white light pouring from it
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I'd rather have... (Score:5, Insightful)
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.
Re:I'd rather have... (Score:5, Insightful)
I am not sure about me. Cut my flight time in two, and now a 2nd class seat seems easier to tolerate.
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Assuming going twice as fast costs 4x, you should compare 8 hours of business class to 4 hours of 2nd class. If your personal space is 3-seat big, there's no pressure.
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I'd rather have a cheaper flight.
Ah yes, the source of most traveler's frustrations with Airlines... You want to check a bag? $$ You want to sit in a more comfortable seat? $$ You want food during the flight? $$$ A carryon? $$
All this because folks want to fly CHEAP over comfort or customer service...
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On many (most?) airlines you can get 'extra leg room' for about a 20% upcharge. If the rows have 2 sets of 3 seats, you could make an 'extra legroom section' by removing 1 row out of a group of 6 rows. You lost 6 seats, so the remaining 30 people in that group would have to make up the difference (20% more each).
However, if you are talking about width, it gets much more expensive. Take that same 3X3 configuration and make it 2x2. Now the remaining 4 people have to make up for the loss of 2 seats, a 50%
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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.
Says the guy who has never flown outside the continental United States. Cheaper, I get. But faster would be really nice. And for the record in the previous decade I once flew on what was the longest regularly scheduled non-stop passenger flight in the world, Singapore Airlines Newark to Singapore flight. Last time I checked, no current regularly scheduled non-stop passenger flight is longer than that was. Sadly, Singapore Airlines decided to convert it to all business class and really misread the dema
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Says the guy who has never flown outside the continental United States.
Quite wrong. I'm not even American. I'm currently in the US, but I'm not American.
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You've obviously not got family in Australia.
Quicker = more comfortable (Score:5, Insightful)
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The vast majority of flights are 2 or 3 hours tops. Sure, for the longer flights it would be great- for most flights, the time spent "in-air between cities" is negligible compared to time going through security, boarding, waiting for takeoff, having plane de-iced, waiting to land, waiting to unboard.
So yes, I'm sure it will be great if you have a 13 hour flight. For your average 2 to 3 hour flight though it's not going to save you a large % of your time spent flying.
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Faster flights would be nice, and it would make some longer trips better. But on relatively short trips the layovers and TSA garbage is what eats up most of the time. There is a 700 mile trip I make a couple times a year. Flying is still an hour or two faster most of the time and I can spend most of the time reading. Driving however is cheaper and minimally slower, I don't have to rent a car when I get there, and I can let the wife pack for the apocalypse.
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Yup... I flew to visit my parents who live about 530 miles, door to door, from my house. The airport nearest to them is smaller, and it costs more to go there, so we end up going to major one about an hour drive from their house. My airport is about an hour drive from my house. Now they used to say arrive an hour ahead of time for domestic, but after the TSA they've added an hour (2 for domestic, 3 for international) to their suggested arrival times... if I roll parking and such into that, that's three h
How many flights overhead within a 30 mile radius? (Score:4, Interesting)
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.
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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
Imperial/US Units worse than you realize (Score:2)
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.
Technica
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Worse than your worse makes it out to be. Most of the hard sciences use metric for just about everything. Physics, chemistry, bio, etc. But engineering often still uses imperial measurements for everything, because engineering stems from design and testing, not first principles, and the design and testing was done a century or more ago. So you'll find slugs and foot-pounds in engineering courses taught on the same campus as the physics classrooms where the same students will be using kg and newtons.
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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.
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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.
FFS, Move Bits Not Atoms (Score:5, Insightful)
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.
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High speed rail require a much higher population than an airport and the terrain can drive the costs nuts. Here in Norway there's 42 official commercial airports, one high speed rail line and it's only from the capital to the capital's airport. They did a survey to see what it would take to hook up our four biggest cities and it was a ridiculous number of billions, lots of tunnels and bridges get the curvature required, securing everything from landslides, floods and avalanches not to mention the maintenanc
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Don't forget kiddos (Score:2)
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Replying to remove mod. Didn't see the sarcastic post title. Carry on...
It's really getting hard to tell these days.
Don't care (Score:5, Interesting)
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
Re: (Score:2)
Indeed, with ramp-up time, ramp-down time (landing), boarding time, and between-hop time; it seems flight speed it not really the bottleneck: it's a case of hurry-up and wait. Maybe it would matter for the rich who buy their way around most of those other things.
Can NASA fix the TSA too? (Score:2)
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
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Surprised no one has posted this yet. (Score:2)
In this video by Wendover Productions on why the Concorde failed [youtube.com], 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.
like a Mercedes-Benz on the interstate? (Score:2)
What does it hum, Deutschland Uber Alles?
I'll believe it when I see it. (Score:4, Informative)
I wanted to say: I believe it when I don't hear it.
Most time is spent with airline drama anyway (Score:2)
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
I remember... (Score:2)
...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.
Re: (Score:3)
Re: (Score:2)
They'll probably look like these [wikipedia.org].
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dB [wikipedia.org] is a log scale unit. 60 dB is not 50 %more than 40. Its 1000 times more power than 40 decibel