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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.
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.
General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
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.
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.
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.
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.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
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