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The Electric Airplane Revolution May Come Sooner Than You Think (robbreport.com)
An anonymous reader shares a report: An all-electric mini-airliner that can go 621 miles on one charge and replace many of the turboprops and light jets in use now -- flying almost as far and almost as fast but for a fraction of the running costs -- could be in service within three years. But this isn't another claim by another overoptimistic purveyor of electric dreams. It's using current technology, and the first planes are being built right now. In fact, the process of gaining certification from aviation regulators for what would be the world's first electric commuter plane has already started.
The pressurised Alice from Israeli company Eviation is a graceful-looking composite aircraft with one propeller at the rear and another at the end of each wing, placed to cut drag from wingtip vortices. Each is driven by a 260 kW electric motor, and they receive power from a 900 kWh lithium ion battery pack.
Alongside its 650 mile range, the pressurised $3 million-plus Alice can carry nine passengers and two crew, and cruise at 276 mph -- up there with the speed of the turboprops that are widely used in the commuter role, if not anywhere near that of jets. But crucially, says Eviation chief executive Omer Bar-Yohay, "operating costs will be just 7 to 9 cents per seat per mile," or about $200 an hour for the whole aircraft, against about $1,000 for turboprop rivals.
The pressurised Alice from Israeli company Eviation is a graceful-looking composite aircraft with one propeller at the rear and another at the end of each wing, placed to cut drag from wingtip vortices. Each is driven by a 260 kW electric motor, and they receive power from a 900 kWh lithium ion battery pack.
Alongside its 650 mile range, the pressurised $3 million-plus Alice can carry nine passengers and two crew, and cruise at 276 mph -- up there with the speed of the turboprops that are widely used in the commuter role, if not anywhere near that of jets. But crucially, says Eviation chief executive Omer Bar-Yohay, "operating costs will be just 7 to 9 cents per seat per mile," or about $200 an hour for the whole aircraft, against about $1,000 for turboprop rivals.
Looked pretty good till I got to the bit about only carrying 9 passengers.
260kw engines x3 = 780 Kw power draw from engines at full throttle. Control surface actuators, radio, aircon, navigation, lighting all have to draw power from the same battery pack... I’d wager this has barely an hour of flight endurance at full engine power. Worse if wing de-icing were also battery powered.
They claim 650 mile range at 276 mph, which is a bit more than two hours flight time... I realize the engines shouldn’t have to be at full throttle for most of a flight, but this still seems like not enough to provide an operating reserve to divert to another airport or wait in a holding pattern for long
If these fly I can only see them being approved for very short hops.
This is a nine-passenger aircraft. No matter how cheap it is, it can't replace a common turboprop commuter aircraft like the Q400, which seats 80-90 people.
Below a certain capacity, the cost-per-seat doesn't matter because airlines can only get so many landing and gate slots, and general aviation airports aren't equipped to deal with the sort of volume that would be needed to replace them... not to mention that general aviation airports are usually MUCH worse accessible in terms of public transit and distance from population centers.
Electric, compared to turboprop/jet, should be very low maintenance. This will also be a huge win for short-haul flights like these.
Google: How often do planes get inspected?
A check. This is performed approximately every 400-600 flight hours or 200–300 cycles (takeoff and landing is considered an aircraft "cycle"), depending on aircraft type. It needs about 50-70 man-hours and is usually on the ground in a hangar for a minimum of 10 hours.
They claim "current technology", but with current technology 900 kWh weigh about 9 tons (considering the battery pack). Ultimate density for Li-ion, according to this report (figure 6-12), could get it to 3 ton or just below.
That's in any case a lot more than the payload for a plane that size. In general, current battery technology cannot be used on regional flights, much less intercontinental ones. Hydrogen may be an alternative for regional (still not long-range), though it might require making the plane look like a beluga to accommodate the tanks.
900 kWh on a 9-seater? Vaporware, unless they show what battery pack they are using.
Victims of 9/11: <3000. Traffic in the US: >30,000/y
Um... no. You can buy an electric airplane such as Pipistrel no problem. And obviously it's possible to scale it up. Question is though, where are the practical engineering and economics limits? Just as obviously as it's possible to scale up electric airplanes, it's currently not feasible to scale it up to rival an intercontinental airliner. But there is a lot of middle ground between a Pipistrel and A350.
Ever seen a Tesla battery pack go up in flames?
Kind of hard to stop and jump out at 20000 feet.
Ever seen what a shotglass worth of vaporized gasoline can do with regards to explosive power?
Kind of hard to use your argument when the risk factor doesn't really change regardless of fuel source.
About 20 years ago, Morton International (now Autoliv) used a private jet to shuttle explosive airbag initiators between the Tremonton, Utah and Brigham City, Utah plants. It was a 20 mile flight and ridiculously-expensive (because Learjet), but the initiators were illegal to transport via the freeway. Ultimately, the Tremonton initiator plant was closed. The airport closed a short time later because that jet was the only real reason it stayed open.
There's a lot of distance between cities in Utah. Brigham City isn't that big at ~18,000 people and it's a 30 mile flight North to Logan with a population of 50,000 or a 30 mile flight South to the Ogden Metro area with a population around 500,000. It's a further 30 miles to the Salt Lake City Metro area with a population over 1,000,000.
Booking full 9-passenger flights between Brigham City and Salt Lake City would be easy. A round-trip would be faster and cheaper than the FrontRunner train (which is supposed to link to Brigham City in the distant future) in terms of operating expenses, even at half-capacity. Engineers, Doctors, etc, who live in the less-crowded Brigham City area already commute to Salt Lake. Saving an extra two or three hours a day on the commute (not to mention the stress of traffic) is something people with the money would gladly pay for.
In a world of the blind, the one-eyed man is king--and the two-eyed man is a heretic.
Li-Ion accumulators have about 0.7 MJ/kg or about 0.3 MJ/lb.
But because the energy efficiency of a jet engine is only about 40 percent, the 16 MJ/lb are more equal to 6.4 MJ/lb compared with Li-Ion, which has a nearly 100 percent efficiency. Still, effective Li-Ion-energy density is only a twentieth of that of jet fuel.
Ever seen a Tesla battery pack go up in flames?
Kind of hard to stop and jump out at 20000 feet.
Ever seen what a shotglass worth of vaporized gasoline can do with regards to explosive power?
Kind of hard to use your argument when the risk factor doesn't really change regardless of fuel source.
Jet fuel as used in commercial turboprop and jet airliners is much more similar to kerosene than gasoline in terms of volatility. Its flashpoint is generally above 38C (depending on exact mix) while gasoline's is minus 43C. Jet fuel will explode if pressurized and vaporized, which is why airplane crashes can produce spectacular explosions, but it is actually difficult to light an open container of jet fuel with a match.
All that to say, uncontrolled combustion, let alone explosion, of jet fuel in a moving aircraft is a very unlikely event.
If you look at hydrocarbons, you mostly have about two hydrogen atoms per carbon atom (less for non-saturated compounds). So it makes sense to talk about mol and not about mass. If you for instance burn octane (C8H18), you get 8 mol CO2 and 9 mol H2O per mol of octane.
It's amazing how often this silly argument turns up with respect to charging electric vehicles. Somebody calculates the peak charging rates and then extrapolates that to some ridiculous amount that has to be supplied continuously from the original source.
People don't do this with other consumables, like water or gasoline. Noone ever says, "a toilet requires 1 gallon to be refilled within 60 seconds. There are 5 million toilets in NYC, so the NYC water system must be designed to supply 5 million gallons per minute". Nope, that's silly, because obviously not all toilets are going to be flushing continuously. Having intermediate water storage allows us to work in terms of average demand, not peak demand.
Well, guess what? You can store electricity, too. Just charge up a large battery at the airport slowly from the utility infrastructure (or hell, from solar panels for that matter) and use that battery to quickly charge planes when they need to be refilled.
The battery just has to be sized based on average demand (with some buffer). This is pretty much exactly how airport fuel tanks work.