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It's depressing how little travel time has changed in the past several decades. The Boeing 747 was introduced in 1970, and we're still traveling at around Mach

It's depressing how little travel time has changed in the past several decades. The Boeing 747 was introduced in 1970, and we're still traveling at around Mach 0.85. In the past four decades, we haven't made any significant improvements to travel time. How sad is that, when in the span of 3 decades in the 1830s, rail travel time doubled? I think (hope) that we're on a path to change this in the near future. The main reason for our lack of advancement in travel time is the cost of gasoline. The Concorde demonstrated that supersonic transport was technically possible, but economically impossible. What will change the landscape is electric planes. This is not a fantasy - there are several companies with (somewhat) viable piston planes being engineered right now. The first company is Beyond Aviation (www.beyond-aviation.com) which is producing an electric varient of the venerable Cessna 172 (most popular plane produced, the default trainer option for pilots). It's not a perfect plane -- only 2 people can ride in it, and it's designed for flight schools, not for cruising around, but it's a big step forward for aviation. The second company is Pipistrel, which is developing the Panthera (http://www.pipistrel.si/plane/panthera/technical-data http://www.pipistrel.si/plane/panthera/technical-data). The Panthera Electro is a huge step in the right direction. Although it only seats 2, and cruises at 118 knots, it can go for 215NM. This is just shy of NYC -> DC. Imagine if you could travel between these cities for essentially free (solar power). On the more viable replace-business-jets route, Elon Musk has stated that he wants to build a VTVL electric jet. From what he's stated, it sounds like his main approach to overcoming the lack of energy density is flying higher. Current jets are limited to efficient operation at ~35k feet because the oxygen density any higher is too low for an ICE to operate. Current li-ion batteries, however, don't need oxygen to operate! So they can go to 50,60,70,80k feet for reduced drag and operate just as efficiently as if they were at 35k feet. Musk has stated that he thinks battery density needs to double before this jet can become a reality (and has shown that battery density doubles once every ~10 years historically). I'm extremely optimistic about the future of aviation. As soon as we can hook up cheap (nuclear, coal, wind, solar) and efficiently generated (~2x efficiency gains at large plants) power to planes, the cost of flying will take a huge drop.

w1ntermute 14y ago
Speaking of Musk, there's the Hyperloop. Not sure why he hasn't announced it yet.
mertd 14y ago
While you are depressed, I am amazed by the quantum leap we made. Up to two centuries ago travel time had been essentially the same for millenia, provided that you could afford a horse. Now I can go to any major city in the world within two days.
starpilot 14y ago
None of the electric aircraft you mention will have performance approaching that of any commercial jetliner. Not in speed, range, and definitely not on cost. It will be that way for a very long time due to the dismal energy density of batteries next to fossil fuels. You know how most powerplants generate power? Turbines, like these GE ones derived from their own jet engines: http://www.ge-energy.com/products_and_services/services/gas_turbines_power_generation_services/index.jsp http://www.ge-energy.com/products_and_services/services/gas_... . Higher altitude isn't everything for speed. You need to generate high-speed exhaust to produce thrust. A gas turbine compresses air and burns it so that explosively shoots out the back. How do you generate this electrically without combustion to raise the pressure? You can't just spin the turbine faster; the blade tips will go supersonic and efficiency will plummet, not to mention material stresses. Supersonic wind tunnels mechanically compress air into huge tanks, sometimes taking weeks to store enough pressure for minutes of runtime, but that obviously wouldn't work for aircraft. Jets already produce power efficiently (constantly running at nearly the same RPM, never idling in traffic) so there's much less incentive to create electric aircraft. The cost of energy from an electric aircraft in $/joule could be higher than that of a fueled one because you're introducing an additional energy conversion. Gas/coal -> turbine -> battery -> turbine versus gas -> turbine. You're also not getting the range benefit from burning off fuel and lightening the aircraft. You shift argument from "aircraft are too slow" to "aircraft are too inefficient," going electric won't fix either. There are applications for electric aircraft, mainly low-speed, long-endurance aircraft that can recharge from solar power without landing, and perhaps more maintainable private aircraft. These will not be challengers to the 0.85 mach 747 though.
- caf 14y ago
  A gas turbine compresses air and burns it so that explosively shoots out the back The high-bypass turbofans used on jet airliners produce most of their thrust by using shaft power to drive a fan that directly accelerates the air. Thrust from the engine exhaust itself contributes a smaller fraction. With electric ducted fans, presumably you would have a higher number of smaller-diameter fans. (That's not to say that I think that large electric passenger aircraft are going to be feasible anytime soon - I don't).
- 14y ago
ubernostrum 14y ago
The Boeing 747 was introduced in 1970, and we're still traveling at around Mach 0.85. In the past four decades, we haven't made any significant improvements to travel time. The market largely seems to have decided that supersonic flights aren't worth the cost or the hassle; the push has been toward slightly smaller, more fuel-efficient twin-engine craft on the long-haul routes. Which pays technological dividends of a different, but less flashy sort. Hence publicity stunts like flying a 747 on one 777 engine (it works, and think what a 1970s-era person seeing a 747 for the first time would think about hearing that).
masklinn 14y ago
> The Boeing 747 was introduced in 1970, and we're still traveling at around Mach 0.85. The Concorde was introduced in 1976, the world has made it rather clear that the speed is not worth the costs.
potatolicious 14y ago
I'm not depressed about it at all. I can now book a direct flight from Seattle to New York for ~$150. Try showing the people of 1970 that - that the middle class can, on a whim, travel all over their own country by air! In the infancy of a technology it always benefits only the rich. IMO the democratization of amazing technology is a far more worthwhile accomplishment than simply advancing the state of the art exclusively for the rich.

w1ntermute 14y ago

Speaking of Musk, there's the Hyperloop. Not sure why he hasn't announced it yet.

mertd 14y ago

While you are depressed, I am amazed by the quantum leap we made. Up to two centuries ago travel time had been essentially the same for millenia, provided that you could afford a horse. Now I can go to any major city in the world within two days.

starpilot 14y ago

None of the electric aircraft you mention will have performance approaching that of any commercial jetliner. Not in speed, range, and definitely not on cost. It will be that way for a very long time due to the dismal energy density of batteries next to fossil fuels. You know how most powerplants generate power? Turbines, like these GE ones derived from their own jet engines: http://www.ge-energy.com/products_and_services/services/gas_turbines_power_generation_services/index.jsp http://www.ge-energy.com/products_and_services/services/gas_... . Higher altitude isn't everything for speed. You need to generate high-speed exhaust to produce thrust. A gas turbine compresses air and burns it so that explosively shoots out the back. How do you generate this electrically without combustion to raise the pressure? You can't just spin the turbine faster; the blade tips will go supersonic and efficiency will plummet, not to mention material stresses. Supersonic wind tunnels mechanically compress air into huge tanks, sometimes taking weeks to store enough pressure for minutes of runtime, but that obviously wouldn't work for aircraft. Jets already produce power efficiently (constantly running at nearly the same RPM, never idling in traffic) so there's much less incentive to create electric aircraft. The cost of energy from an electric aircraft in $/joule could be higher than that of a fueled one because you're introducing an additional energy conversion. Gas/coal -> turbine -> battery -> turbine versus gas -> turbine. You're also not getting the range benefit from burning off fuel and lightening the aircraft. You shift argument from "aircraft are too slow" to "aircraft are too inefficient," going electric won't fix either. There are applications for electric aircraft, mainly low-speed, long-endurance aircraft that can recharge from solar power without landing, and perhaps more maintainable private aircraft. These will not be challengers to the 0.85 mach 747 though.

caf 14y ago
A gas turbine compresses air and burns it so that explosively shoots out the back The high-bypass turbofans used on jet airliners produce most of their thrust by using shaft power to drive a fan that directly accelerates the air. Thrust from the engine exhaust itself contributes a smaller fraction. With electric ducted fans, presumably you would have a higher number of smaller-diameter fans. (That's not to say that I think that large electric passenger aircraft are going to be feasible anytime soon - I don't).
14y ago

ubernostrum 14y ago

The Boeing 747 was introduced in 1970, and we're still traveling at around Mach 0.85. In the past four decades, we haven't made any significant improvements to travel time. The market largely seems to have decided that supersonic flights aren't worth the cost or the hassle; the push has been toward slightly smaller, more fuel-efficient twin-engine craft on the long-haul routes. Which pays technological dividends of a different, but less flashy sort. Hence publicity stunts like flying a 747 on one 777 engine (it works, and think what a 1970s-era person seeing a 747 for the first time would think about hearing that).

masklinn 14y ago

> The Boeing 747 was introduced in 1970, and we're still traveling at around Mach 0.85. The Concorde was introduced in 1976, the world has made it rather clear that the speed is not worth the costs.

potatolicious 14y ago

I'm not depressed about it at all. I can now book a direct flight from Seattle to New York for ~$150. Try showing the people of 1970 that - that the middle class can, on a whim, travel all over their own country by air! In the infancy of a technology it always benefits only the rich. IMO the democratization of amazing technology is a far more worthwhile accomplishment than simply advancing the state of the art exclusively for the rich.