Slashdot Mirror
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.
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
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!
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.
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.
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
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
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.
I wanted to say: I believe it when I don't hear it.
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.
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.
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.
I am TheRaven on Soylent News
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).
CLI paste? paste.pr0.tips!