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Proposed Lapcat II Hypersonic Airliner: Brussels to Sydney in Less Than 3 Hours
New submitter AG_2011 writes: Could an airliner that flies anywhere in under 3 hours be in service by 2030? One estimate puts the cost one way at €5,000 (£3,700) per seat for a Brussels to Sydney trip. The Lapcat-II project's Mach 8 airliner will be capable of 8,500 km/h (5,280 mph) and could take passengers on this trip in 2 hours and 55 minutes. The race is on...
Three hours: airport security checks
Three hours: flight time
Three hours: customs
Not bad. Not bad at all.
who would want to do that?
The actual plane ride is actually quite nice. You can get up and stretch your legs, get refreshments and whatnot. The crappy part is getting to the airport, check-in, security control, boarding, disembarking, waiting for luggage, getting from the airport and so on. Going to the capital is ~50 minutes flight time, but in practice city center to city center it's 3.5-4 hours. Now I suppose for the really, really, really long flights this could be an advantage but for the somewhat shorter trips within 1000 km I'd rather see end-to-end high speed rail.
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Until we can keep reliable low-supersonic passenger service flying, I'm really not going to worry about the hype of hypersonic.
Give me LA to London in six hours for a price I'm willing to pay as an already frequent flyer, then we'll start talking.
Do not look into laser with remaining eye.
This one of the few good uses for hydrogen fuel that I've seen other than rockets. However, I suspect it will be too loud for passenger traffic. The Concorde was notoriously noisy, even aside from the sonic booms it created.
There are few flights long enough for this to be worthwhile, especially if the courts limit the areas they can travel at transonic speeds. At the least, I would want government involvement minimized.
a,e,i,o,u and sometimes w and y (at be if of up cwm by)
One estimate puts the cost one way at €5,000 (£3,700) per seat for a Brussels to Sydney trip.
Does that price include any amortized R&D expenses? I somehow doubt it.
If the hydrogen can be sourced from natural gas, instead of from the electrolysis of water, the airfare tickets of a hypersonic trip could drop to about half the price of a business-class ticket.
Based on current projections the ticket price will be about three times more expensive on average than current business-class subsonic tickets.
Yes, these two sentences followed each other. There was no editing.
So the cost could be about half as much, but they'll charge three times as much because they can. I suppose I can't blame them--if I was in Brussels, I'd probably pay three times the going rate to get to Sydney.
So that everyone can have an informed opinion about this, the laws of physics of high-speed travel are quite simple. The lower the lift-drag ratio of your craft (at cruise speed at level flight), the more fuel you have to consume per mile. The problem with supersonic travel is that at supersonic speeds, high lift-drag ratios become virtually impossible. A 747 has a L/D ratio of over 25; the Concorde had a L/D of about 7 at Mach 2 (and it was a pretty efficient, low-drag design). The best supersonic designs I'm aware of achieve a L/D of around 9 at L/D at Mach 1.5. These are incredibly optimized designs that have been fine-tuned with supercomputers and would be quite unfeasible for a passenger aircraft (weird shapes, no windows, etc.) As a result the Concorde consumed about 3x more fuel PER MILE than a comparable subsonic jet. So half the mass of the Concorde was fuel (!), it winded up being very heavy, and it carried only 100 passengers. And its maximum range was limited to 4500 miles.
And if you look at a craft like the SR-71 blackbird, it fits the same pattern. It had a L/D of about 6 at cruise speed (Mach 3.2), 60% of its mass was fuel, and it could only go about 3000 miles before requiring refuelling.
At hypersonic speeds, it's even worse, as various laws start catching up with you and limiting your theoretical L/D to about 4 or 5. If you're running on typical jet fuel, forget London to Sydney. Such a craft could barely make it from London to Athens. So because of that, they're suggesting hydrogen. Which is both hilarious and also firmly puts this idea in the realm of 'things that are never going to happen.'
A fool and his hard drive are soon parted.
It used to be economic to spend a month on a ship, paying hotel rates for labour but thats just too expensive now, so you pay less money to spend a day on a plane to go half way around the Earth. But at some point the cost of labour will rise to the point where that one day is too expensive as well, so it will be economic to develop faster aircraft which cost less in manpower to run. Even now an SST could get away with less in cabin staff, fewer changes of crew, etc.
http://michaelsmith.id.au
Good tech, but why doesn't a project for the elitist rich bother Europeans? And subsidized at that?
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
It failed because the cost of tickets was unsustainable, and they couldn't get the price down to where enough people would buy them to make it financially viable.
This will be the fate of any future super-high-speed mode of travel, if they can't get the cost down enough so that ticket prices can compete with traditional air travel.
retired 'cause rich people died. rent-a-jet took that market.
I'll just hop in my flying car to get to the airport and catch my flight in it.
"What’s more, liquid hydrogen fuel is not highly combustible mid-flight. Although hydrogen can be ignited, the risks of an explosion or fire are lower compared to conventional airline kerosene fuel"
Gaseous hydrogen is already a ridiculous explosive risk. Liquifying it only makes the resulting explosions bigger. They somehow think this is safer than Jet-A, which is actually less flammable than gasoline.
There are valid engineering reasons for the use of liquid hydrogen as a fuel, such as specific impulse or heat capacity. But safety is absolutely not one of them.
In other news, this is a blatantly obvious attempt to get funding for SSTO spacecraft development by disguising it as a less outlandish business plan. Seriously, this has much more in common with Skylon or VentureStar than with Concorde, right down to the choice of fuel. I wouldn't be surprised if many of the engineers are the same.
Should be on $. news for the rich who can afford such things :|
Cashdot: News for the wealthy, stuff that's expensive?
If it weren't for deadlines, nothing would be late.
I wonder if that makes the jet lag worse.
"If any question why we died, Tell them because our fathers lied."
Why not Mach 22
If you first want to go fast, why not just use an intercontinental ballistic missile? It is really simple construction (read fuel tank with orifice), uses cheap fuel, and really need no fancy aerodynamics or control system. Just aim and fire.
The whole idea of pushing a vessel through air for hours and hours, wasting fuel, when it can glide with no friction a few miles higher seems dumb. It also consumes more fuel in total.
don't cut it off www.mgmbill.org
How much will it cost to change the rules about sonic booms, and what's going to be the window replacement cost for people under the flight?
_ _ _ Go for the eyes Boo! GO FOR THE EYES!
Hydrogen is a terrible fuel. It has no good uses.
What about solar power? Most stars, including ours, tend to burn hydrogen.
Is it a great fuel for stars?
Meh.
Hydrogen is a lot cheaper as a fuel, unless you source it stupidly, like they did in the article (they assumed no use of methane precursor, only electrolysis), and a Miele design will hit an L/D ratio of ~14 at low Mach numbers (e.g. Mach 2), which compares favorably with the Boeing 747 L/D ratio of 17 at Mach 0.85.
A Miele design will drop to an L/D ratio of about 7, but it takes going Mach 30 to get there. You can easily do an L/D ratio of 8, if you don't plan on going over Mach 5 with the thing -- and methane derived hydrogen fuel is far cheaper than jet fuel.
http://www.aerospaceweb.org/de...
My take-away on the article was: written by someone who doesn't want sonic booms (he states that the Concorde had booms as loud as 135 dB, but states in the same sentence that booms are 160 dB.
They have it all wrong. In 15 years, the pinnacle of commercial airplanes won't be shiny, fast and high tech. They will be more like buses or trains: slow, boring, reliable and affordable.
They're already slow, boring and reliable. Where I disagree is that I don't see them getting a whole lot more affordable in 15 years. Fuel and maintenance costs should continue to drop as more old planes are replaced with current and upcoming models but ticket prices have only gone up. People will continue to pay high prices for air travel unless ground travel suddenly becomes a whole lot quicker and we build highways and railroads over large bodies of water. We all seem to hate airlines, but what are you going to do, go Greyhound? Yeah, right. Air travel will continue to be both expensive and popular for the foreseeable future, especially but not only in America. Not every place has a rail system like Western Europe, nor is as compact.
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As pointed out by others the problem with faster aircraft is that a large portion of a traveler's time is spent standing in line at airports, not in the airplane. Few people travel at such great distances that such an increase in speed proves beneficial in decreasing travel time. What would be more beneficial is to reduce the time standing in lines at the airport.
We have a conflict of interests here. Bigger planes are cheaper to run. Bigger planes take more time to fill and, since they move more people at a time, need to run less often. Smaller planes take less time to fill, would need to run more often, reducing travel time.
I see the future of air travel being run more like a subway station. I show up at the station, pay my fare, and then I am free to get on any plane that has room for my butt in a seat. If the plane I want to be on is full then I wait 20 minutes for the next one. I should not have to pass through a metal detector or have to take off my shoes any more than if I was getting on a train or bus.
Domestic travel would be more likely to run like a subway station, international travel could be quite different. This hypersonic plane would not change the need for things like customs, which is where a lot of the waiting would be.
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How come noone seems to address the issue of the very high cosmic radiation exposure at such a high flight alitude? Sure, because of the shortened travel time, the effect would be somehow mitigated, but would it be enough to complete compensate? Seems to me passengers will have to wear space suits :p
Du kan glomma dina ensama stunder, du kan lita paa teknikens under - Wilmer X
This probably won't happen. Yet another pie in the sky proposal that'll lead nowhere, such as the British Skylon project. The reality is that Concorde required considerable national investment from the Great Britain and France. With the advent of high speed internet, the need to shift an actual human at high speed from A to B is lessened - this is why we now have two double decker models of passenger jet (747-400 and A380) and no supersonic airliners (either TU-144 or Concorde). Shifting materiel is done at a leisurely 23 knots on a cargo ship. I'm not necessarily happy with the way things have panned out, but that's nevertheless how they have. :(
*Insert ridiculous, apparently intelligent but ultimately meaningless phrase here*
> Electric cars are not inherently "green" since a large portion of our electricity comes from coal and natural gas.
You're right about the hydrogen, but wrong about this. Electric cars ARE green because internal combustion engines are really, really, and I do mean really, inefficient. If you do the math, the typical electric car in the USA produces 2-4x times less emissions than a gas car (even taking electricity production into account). And in places where the electricity is generated cleanly, they produce zero emissions.
A fool and his hard drive are soon parted.
Just once difference, we're talking Brussels to Sydney. The answer is more:
15min security check
1.5 hours binge shopping duty free goods and sipping on latte at the gate. Bonus points if you get to spend it in the lounge with a nice whiskey.
3 hours flight time.
10min bag wait.
10min customs.
Don't let America ruin flying for you. Not every country in the world is batshit stupid when it comes to air security.
Assuming an electric car gets twice the thermal efficiency compared to a petrol car I'll do some math. A coal powered electric car is powered solely by the carbon bonds on coal, that means every joule comes from turning carbon and oxygen into CO2. A petrol powered car gets roughly half its power from the carbon bonds and half from the hydrogen bonds. If the petrol car is getting half of its energy from turning hydrogen and oxygen into H2O then it's producing the same amount of CO2 per mile traveled.
If we compare the coal powered electric car to a car run on methane then we get better numbers. For every carbon atom burned in that methane we get four hydrogen atoms burned. Which by my back of the envelope math the methane burning car is just as good, or better, than the coal powered electric car that has four times the thermal efficiency.
No one in the USA can claim a "green" electric car because in the USA 80% of our electricity comes from coal or other fossil fuels. Even if someone owns an electric car, and charges it from their own solar panels, it's still not carbon neutral since the aluminum and steel used to make that car came from coal powered factories.
What we might have is a bit of a chicken and egg question. What comes first, the electric car or the nuclear power? It's difficult to justify the electric car with coal power and so long as cars burn petrol a nuclear power plant does nothing to reduce emissions from vehicles. As long as we get so much of our electricity from coal it seems obvious to me to make the transition from coal to nuclear as soon as possible. After we have a majority of our electricity from nuclear power then it might make sense for electric vehicles from a standpoint of CO2 emissions. Even then we'd still have a problem with the financial cost of electric vehicles. Perhaps electric cars will become cheaper in time but I doubt it. I'd think that natural gas would get so cheap from not having to burn it for electricity that using it in cars would make a lot of sense, both financially and from a CO2 output stance.
That's just my math though. You can do your own math if you like. Please share your math if you think you get numbers that show electric cars are superior to natural gas cars.
I am armed because I am free. I am free because I am armed.
This plane would take 2.5 hours to go up and come back minimum. Crossing the half the globe at the higher atmosphere is just 25 minutes. So the flight times are like: 2hr 30 min for Brussels to Brussels, 2 hr 35 min for Doha, 2hr 40 min for Delhi, 2hr 45 min for Manila, 2hr 50 min for Sydney!
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Video conferencing has gotten so good, the demand for fast business travel is shrinking. I find it hard to believe there is enough market for pleasure travel at supersonic speed to support it; especially if it means traveling to an intermediate hub airport versus a slower but non-stop flight
Super Fast Lapcat II Hypersonic Airliner reaches you within 3 hours from Brussels to Sydney. That's sounds great news with airport security checks for US.
Okay then, I will revise my math. The g/kWhr for energy to moving the vehicles becomes:
900 / 50% = 1800 for coal-electric vehicle (CEV)
800 / 25% = 3200 for petrol powered vehicle (PPV)
500 / 25% = 2000 for natural gas vehicle (NGV)
At this point the life cycle carbon output comes into play. How much more heavy metals are needed for the batteries in the CEV vs. the NGV? How much more mining and refining is needed to produce those batteries?
I will admit my back of the envelope math was off by a bit I was still well within order of magnitude. Electric vehicles are not the "zero emission" vehicles they claim to be so long as we burn coal for electricity.
To be fair I'll add the 20% factor for electricity made from "green" nuclear, hydro, and wind.
900 / 50% * 80% = 1440 for coal-electric vehicle (CEV)
Even that makes CEV and NGV within 30% to 40% of each other. New engines announced this last year claims to increase internal combustion efficiency to 40%, making total vehicle efficiency close to 33%.
500 / 33% = 1500 for natural gas vehicle (NGV)
That puts NGVs at near parity with CEVs. Then there are some real bonuses for natural gas beyond being "green". Cost is a big one, as NGVs share many parts with PPVs that makes production and repairs inexpensive and easy to find. There is the possibility for dual fuel with petrol from those that have difficulty finding natural gas stations. CEVs can share this as a plug in hybrid but that adds to the cost, weight, and the reduction in efficiency that comes with that weight. NGVs have increased range between fill ups and reduced time to fill up compared to CEVs;.
Not all bad things for CEVs. Electric motors can achieve performance and noise reduction that internal combustion vehicles cannot match. If natural gas/petrol dual fuel electric plug-in hybrids come to market then we get the best of them all, IMHO.
I am armed because I am free. I am free because I am armed.
> Assuming an electric car gets twice the thermal efficiency compared to a petrol car I'll do some math
Your very starting assumption is wrong. ICE engines are, at best, 25% efficient. This is for hybrids; old-school gas cars are closer to 16 or 17% efficiency. When I said they're very inefficient, I meant it.
Electrical engines are very efficient. 90% efficiencies aren't unusual. The Tesla Model S gets 68% wall-to-wheels efficiency (from plug to battery to motor to wheels).
So adjust your math from 2x to 4x.
A fool and his hard drive are soon parted.