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Airbus E-Fan Electric Aircraft Makes First Flight
An anonymous reader writes "The aviation industry has taken a tentative step toward electric power with the successful maiden flight of the Airbus E-Fan. The manufacturer known for the massive A380 jetliner began testing this small experimental aircraft last week, with the ultimate aim of lowering the huge carbon dioxide emissions from commercial flights. The E-FAN is powered by 120 lithium-polymer batteries, and can fly at speeds up to 136mph. Measuring just 19 feet from nose to tail, the compact aircraft show that Airbus probably isn't ready for commercial zero emissions flight just yet, but it does highlight the potential benefits."
For this version of the plane.
http://en.wikipedia.org/wiki/A...
If it was so practical, why did they wholly cut funding. Seems like they had a long way to go to make the nuclear design feasible to where the crew was safe.
And how many civilians would fly with a nuclear reactor?
Replacing the nuclear reactor with batteries means A LOT of batteries. So I'm not sure how you can claim the whole idea is feasible just from a working nuclear design.
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Great range, zero emissions, they've already been tested.
This is very doable.
http://en.wikipedia.org/wiki/N...
And I don't see any potential downsides
Did any of those tests actually conclude that they're viable? As I read the wiki, it seems the entire testing involved validating the shielding worked. Did the planes actually get powered by the nuclear engines?
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The aft main wheel includes an electric motor with 6kW power, which provides taxiing and acceleration up to 60km/h during the take-off
This may give the "plane on a treadmill" problem a bit more traction.
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YES zero-emissions! The vehicle emits no carbon dioxide.
Using electric vehicles (planes, trains or automobiles) is not just about shifting the CO2 emission point.
It allows use of energy sources that would not otherwise be viable for transportation (liquid hydrocarbons have a significant premium over other forms such as gas or solids). In addition land based power facilities have significantly higher efficiencies (open cycle gas turbines are lucky to get 40% efficiency, stick a waste heat recovery boiler on the back end and it is up to 60% efficiency).
The other alternative fuel for air transport I can see would be LNG (liquified natural gas), at that point we need several generations of improvement in scramjet technologies (air breathing rockets anyone?).
The power output of a Boeing 747 is 140 MW according to a slightly unreliable Wikipedia list. Now, this is probably the total engine output, but you would certainly need a significant fraction of that in electrical power for propellers. Note the other number in that list? A full Nimitz-class destroyer is 190 MW (that seems to be electrical power). A nuclear submarine does not even come close. The cooling environment of that 20 ton reactor is probably quite different, too. You can cool off the rector coolant against the ocean. Not so at 30,000 feet.
That's still a good amount of time to be useful for things like island hopping.
The article states endurance between 45 minutes and 1 hour. But lets be optimistic and assume 1 hour ...
... maybe a 60 mile one way (plane stays and has time for recharge) or 25 mile round trip (plane immediately returns)?
:-)
Not all that time is "available", at *least* 20 minutes should be reserved for safety. Lets subtract 5 minutes at each end for traffic patterns. So we're really looking at something closer to 30 minutes in practice.
Once you factor in taxiing, climb, descent, etc
Now if you are being pessimistic and going with a 45 minute endurance then we're looking at about 15 minutes in practice. Maybe a 25 mile one way flight?
Yes those numbers are not linear. The difference between 1 hour and 45 minute duration is coming entirely out of cruise time. Safety margin, traffic, ascent, descent, taxiing, etc are unchanged.
That said, this aircraft is incredible. But it is only a technology demonstrator.
However it should be awarded bonus points for resembling the A-10 a little.
It is getting old, and it proves your intelligence that you keep repeating it.
It keeps getting repeated because people keep misusing the term "zero emission". When you use an absolute term such as "zero emission" it is either true or false. In this case "zero emission" is false. All electricity from the grid, which is where these aircraft will probably be charged from, has some component of fossil fuel based generation. Therefore by using grid power the aircraft is causing emission; just on another location.
How much pollution went into making that gallon of fuel?
No one claimed fossil fuels were zero emission.
What the poster is trying to get at is to use a more accurate term such as "low emission" which is a true statement.
So which is worse - carbon footprint or trying to dispose of nuclear waste. Either way, there is no such thing as a zero-emission engine. Somewhere there is something that is creating waste products that have to be dealt with.
4th generation nuclear reactors will use the waste of previous generation reactors as fuel. So dealing with current waste is storing it for 30 years until the 4th gen reactors arrive commercially (research reactors are already running) and can burn it up as fuel. The waste from the 4th gen is far less dangerous and only remains hazardous for a few hundred years rather than tens of thousands.
3rd gen reactors are starting commercial construction and while they don't have the waste/fuel benefits of 4th gen they are much safer than previous generations.
The electric motor really doesn't change the difficulty of flying. In a small training aircraft, engine management is a very minor part of the workload.
Jet fuel has at least 50 times the energy density of lithium batteries ...
And various aircraft ranging from a Boeing 777 to a US Navy F/A-18 have been flown using aviation biofuel, carbon neutral. Its experimental an hellaciously expensive but its a more realistic future.
The vehicle itself is zero emission. The cost, environmentally and otherwise, of fuel and production, while important, are separate issues that need to be addressed separately.
If you try to solve a large, complex, problem in toto, you will likely fail. Breaking it up into manageable pieces is much more likely to succeed, such as starting with the end user product where you get the most bang for the buck and then work up the chain. Transportation is the biggest problem which will take the longest time to effect a transition, so getting started on it is important.
Once you have the transition to electric vehicles underway, then you can work on the dirtiest of the electric supplies and every time you make the supply cleaner, you automatically make everything powered by that supply cleaner, magnifying the effect of that effort.
Trying to claim a zero emission vehicle isn't zero emission is just trying to confuse issues and holds back progress.
Can we please stop trying to insinuate that electric vehicles do not have a carbon footprint?
Until the energy density of batteries goes up and and we have an efficient, carbon dioxide free way to charge them, I'm not sure I see the value here.
Sort-of agree, and energy density is definitely a problem with batteries in any application. However, batteries make a LOT of sense when it comes to a carbon-neutral way to charge them. With a conventional engine you're almost always limited to fossil fuels. With a battery you could still end up burning coal to charge, but you've decoupled the ultimate power source from the plane so you don't HAVE to use fossil fuels. The battery could be charged by nuclear, even though you could never put a reactor on a plane.
I doubt we'll see an electric airliner anytime soon. Where you might see them is for recreational aircraft. Many pilots just buzz around locally for a while and land, and battery power might be ideal for this - there is no urgency to refuel quickly, maintenance could be lower, aircraft could be quieter, no leaded fuel, cheaper costs, etc.
All from the coal plant? Ermmm...not so much.
I get your point, but even with fossil fuels it is often better to use a battery. The little engine on a plane tends to be inefficient compared to a massive power plant, and has fewer practical options for emissions controls. A power point is a concentrated emissions point and investments can be made to make it more efficient and to control emissions. Efficiency improves CO2 output, and emissions controls helps get rid of everything else.
So, even with coal power you're still better off getting things onto the grid vs burning gasoline. It also makes it easier to adopt renewable energy.
I have no idea if this would help, but with developments in solar technology, would it make a significant difference if the tops of the wings, fuselage, tail and fan ducts were all solar panels? Seems like a simple thing to do to help with range... maybe not done because it's not reliable.
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If you try to solve a large, complex, problem in toto, you will likely fail.
By claiming zero emissions you claim to have solved the complex problem when it is far from the truth. By claiming low emissions you admit the fact that work still needs to be done.
Trying to claim a zero emission vehicle isn't zero emission is just trying to confuse issues and holds back progress.
Trying to claim zero emission when there are emissions confuses issues by claiming victory when victory has yet to be won. It also holds back progress. Why spend money on a fight when it is already won. By sweeping the fact that electric vehicles cause emission under the rug you hide the problem. How about the truth by admitting that electric vehicles cause emissions and we can work harder to decrease those emission further.
But they have been successfully used on German zepplins in the 1930ties. They are a bit heavier than otto engines of the same hp, but that is offset by needing 40% less fuel. Something that matters a lot when doing transatlantic flights. They are also more reliable and more suitable to turbo charging, wich is essential on greater hights.