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Hypersonic Flight ‘Breakthrough’ Could Have Us in Tokyo by Lunch
- djisjke 14y ago"could have us", who is us?
- wkearney99 14y agoWhich still doesn't change the times involved getting to and from the airport. These are often worse than the flights themselves. Better to engage remotely rather than travel at all.
- michaelochurch 14y agoMeh... you know what I want? I want to be able to go to Tokyo and not have the ticket cost multiple fucking days of work. In 2012, four-digit airfares for coach are fucking inexcusable. We were supposed to be better than that, 20 years ago. And don't get me started on business class: those tickets are more than some people in the world make in a fucking year. I want travel that doesn't belch a bunch of CO2 into the air, leaving our grandchildren with a world where there are palm trees in Winnipeg and a year-round hurricane season. That's what I care about. If this Mach-5 travel costs the same as airfare currently does, and burns a bunch of fucking hydrocarbons to get there, then I'm not impressed. I'm sure the technology is cool, but would someone please solve the real problem? The real problem is that transportation hasn't improved since the 1960s. In the US, we call exorbitantly-priced, 130-mph trains "high speed", we use airplanes for mid-distance travel and it's ass-expensive as it should be because it makes no economic sense, and most of our transportation relies on burning fossil fuels in tin cans that can't be safely operated above about 90 miles per hour. Solve that one, please.
- melling 14y agoWhat are you talking about? China has almost 5000 miles of high-speed rail that runs over 150mph. Japan is hard at work on replacing their "slow" 186mph trains with 310mph maglev trains. http://www.bbc.co.uk/newsround/20512131 http://www.bbc.co.uk/newsround/20512131 Tesla is hard at work selling electric cars and making a profit. Google has a self-driving car that works. People are solving problems. Getting hypersonic jets to work would be great. Now the problem of getting people to adopt any of this in the US? Engineers can't solve those problems. Someday the US will finally get a real high-speed train, but it looks like Japan will have maglevs first.
- michaelochurch 14y agoMy bitching was largely US-centric. I should have clarified that. However, high airfares are a world-scale problem. My malaise is more general. In the 1950s-60s, the economy was growing at 5-6 percent per year because people actually had the vision to invest in basic research and technology. In this day in age, we have a million IUsedThisToilet.com startups built to be acquired, but very little effort going toward real work.
- Osmium 14y agoThe last few flights I've taken, 60% of the ticket price has been taxes. I understand the need for taxation, but that seems a little absurd to me. It'd be a really quick way of slashing ticket prices...
- c1u 14y agoTransportation CO2 emissions make up a tiny fraction of total greenhouse gases. Water vapour is by FAR the biggest greenhouse gas. I wonder if a 787 burns more hydrocarbons flying 250 people from NY to LA than 250 cars driving that distance? Roughly ~9000gal (2500mi 787 @ cruise) is 36gal per car. Assuming everyone gets perfect highway mileage even if they're Prius it wont get them the whole way (50MPG*36gal=1800mi). And that's not considering the energy required to build and maintain 250 Prius cars vs. the cost of one 787. The retail cost alone for 250 Prius is nearly $90M. A 787 is more like $250M, but lasts a least 3x longer than a car. Transportation has improved since the 1960 by a HUGE amount. Modern cars, trains, and airplanes are significantly better (safer, cheaper, more efficient) than those in the 1960s. I'm curious how much travelling you did in the 1960s compared to today?
- lauraura 14y agoTransportation CO2 emissions make up a tiny fraction of total greenhouse gases. Water vapour is by FAR the biggest greenhouse gas. Water vapor is the largest greenhouse gas, but it's a relatively constant contribution; it's not part of anthropogenic contributions to greenhouse gases (which is usually what people are referring to in this sort of context).
- c1u 14y agoGood point. I'm not trying to start an off-topic climate change debate, just trying to step back and look at the problem a little more broadly, but there's at least one big error in my calcs as has been pointed out.
- drp 14y ago250 * 30,000 = 7,500,000
- c1u 14y agoah! whoops, one too many zeros (I used $35K) :P
- cpleppert 14y ago>> The real problem is that transportation hasn't improved since the 1960s. Yes it has. Guess what? There are a lot more people and they want to travel just like you, basic supply and demand. Planes are far more advanced then they were back then. >>That's what I care about. If this Mach-5 travel costs the same as airfare currently does, and burns a bunch of fucking hydrocarbons to get there, then I'm not impressed. It will cost more and burn even more hydrocarbons(Of course skylon is an unrealistic satellite launch system and this article makes no sense ). Engineering problems are hard, the development work done in the 1960s is child's play to what is being done now. If things suck so much you should be happy that you will change things for everyone and make a bunch of money in the process. >> In the US, we call exorbitantly-priced, 130-mph trains "high speed" They are exorbitantly priced anywhere. We don't get anywhere close to that over an entire distance because existing and even proposed systems (California) won't be fully high speed lines. That isn't a question of technology just simple budget and priorities. No country in the world has replaced mid-distance travel with high speed rail. France is barely finishing out its high speed network that covers a much smaller country than ours.
- imperio59 14y agoI thought another big issue with flying at such fast speeds was that you end up tearing pieces off your fuselage every time... This looks like one piece of a bigger puzzle to achieve what the headline of the article is suggesting.
- loeg 14y agoThat and cost. No one is willing to pay for supersonic flight, and the sonic boom makes it obnoxious over land.
- jasonwatkinspdx 14y agoSkylon could fly high enough to moot sonic boom issues, but I think you're right about lack of market demand for transportation. I think aerospace folks may underestimate how continued advances in communication networks will erode demand for travel of all forms, let alone prompt travel. Of course the military will always be giddy about dropping bombs on whatever poor soul they want as promptly as possible...
- NickPollard 14y agoPeople are willing to pay for supersonic flight. Concorde made a profit on most of it's flights, and it was only after the World Trade Center attacks and subsequent downturn in international commercial flight that it became a problem. Also, because not many Concordes were made, the R&D costs were never properly amortized. The sonic boom however is an issue - Concorde was limited to a small selection of routes that passed mainly over water (e.g. London -> New York) because it was not allowed to go supersonic over a lot of countries. If you could fly supersonic all the way from London to Tokyo, or San Fransisco, or Sydney, then I'm sure it would be worth even more.
- frozenport 14y agoI think 9/11 was coincidental and unrelated. The important trend in 2001+ was the growth of telecommunications phenomena that reduced travel demand. I am not sure if the sonic boom was nearly as big a problem as it was made out to be. I think we can do some cursory math. If 30% was at 50% of the speed, the total distance covered would be 85% less, adding about 20% flight time increase. Something that normally takes 8+ hours now take 3 or 4 hours. Did this kill the concord?
- omegant 14y agoI wonder if it would have any effect adding a statoreactor tube to the end of a rocket engine ( as a kind of postcombustion chamber) to take advantage of all that heat. Maybe adding some fuel to that part to make use of atmosferic oxigen to increase power. Above 30km you may drop it. I don't think it would be too heavy as it doesn't have moving parts. The question is if it would generate power enough to be worth all the trouble.
- jasonwatkinspdx 14y agoI'm not sure I understand what you're suggesting, but it sounds like some form of ram afterburner?
- omegant 14y agoYes exactly. Has it been done or studied?.
- jasonwatkinspdx 14y agoI do not understand how the physics of a ram afterburner would work. A ram duct generates compression via aerodynamic drag. It slows and compresses the air forced into it by controlling shocks. The expansion stage of a brayton cycle engine maximizes exhaust velocity rearward and hence by Newton's third law creates thrust. Constricting the exhaust will only reduce efficiency. If you're talking about an expansion duct with secondary combustion, that has nothing to do with ram effect and is just an afterburner. By and large afterburners are hideously inefficient, but many military craft still include them because it is easier to manufacture an afterburner tolerant of secondary combustion temperatures than a turbine. SABRE erodes this motivation as the incident temperature into the flame holders (or rocket nozzles) is dramatically lower than common in a turbine engine, so you can get more of the energy possible from the oxygen density of the engine's intake flow without secondary combustion.
- ForwardShadow 14y agoThey'll probably never let humans travel by air at hypersonic speeds, its far to dangerous. They'll simply use Evacuated tube maglev(Elon Musk's HYPERLOOP) for long distances, same hypersonic speed. Looking forward to breakfast in San Fransisco, Lunch in LA, and Dinner in Washinton DC.
- ZoFreX 14y agoWhy is it far too dangerous?
- sliverstorm 14y agoHaven't they let humans travel by air at hypersonic speeds already? http://en.wikipedia.org/wiki/Concorde http://en.wikipedia.org/wiki/Concorde
- dalke 14y agoConcorde has a max speed of just over Mach 2.0. Hypersonic means Mach 5.0 or higher. The rocket-powered X-15 max speed was 6.7, and of course the Space Shuttle also went faster than Mach 5.0, so yes, humans have already flown at hypersonic speeds.
- sliverstorm 14y agoHYPERsonic means Mach 5.0 or higher Whoops.
- raverbashing 14y agoAnd of course, if you leave NYC after breakfast and head to Tokio you won't get there by lunch More likely you'll get there for dinner and a night out At Mach 5 this will take 2h (not considering acceleration/deceleration times)
- harshpotatoes 14y agoOf course, assuming they allow supersonic flights over the continental united states. I imagine it would probably be severely restricted due to the noise concerns from the sonic boom.
- carbocation 14y agoThe great circle route from NYC to Tokyo flies over virtually no part of the continental United States, aside from New York. (Canada, on the other hand, would be below the plane for much of the trip, but is sparsely populated enough if the north that I suspect you could route around major population centers easily.)
- raverbashing 14y agoExactly, you have to worry mostly about the coldest parts of Canada and maybe Russia http://www.gcmap.com/mapui?P=NRT-JFK http://www.gcmap.com/mapui?P=NRT-JFK
- harshpotatoes 14y agoOk, thats a good point. I'm not farmiliar enough with the globe to remember the great circle routes.
- stygianguest 14y agoThen standing in line for two hours at security will be even more ironic.
- da3da 14y agoDoes this happen anymore? I flew out of Boston the day before Thanksgiving (when I would imagine tons of people are traveling) and it took <5 minutes to get through security. Same thing on the way back.
- ColinWright 14y agoAlso discussed extensively here: http://news.ycombinator.com/item?id=4842867 http://news.ycombinator.com/item?id=4842867
- michael_miller 14y agoDoes anyone know how practical this is? Is it economically feasible to do this on a jetliner, at Concorde prices? A business jet?
- mvkel 14y agoThe engine has never been the problem. Heat dissipation is the problem.