The ability to fly lower means it won’t have to spend time climbing

Sunday, July 30th, 2023

Eviation, a Washington State-based startup aiming to be one of the first companies to produce electric planes for commercial use, says its electric planes due in 2027 will make air travel less costly and cleaner:

The Alice is a nine-seater aircraft with a length of around 57 feet and a wingspan of 62 feet. These dimensions put it in the ballpark of a Cessna Citation Excel or a Piaggio P.180 Avanti. “I like to say that we found the sweet spot for electric aviation with this aircraft: we have a nine-passenger plane,” Aviation CEO Gregory Davis told InsideEVs. “You can fly with a single pilot in North America, so it means that it is more cost-effective to operate than a ten-passenger plane where you need two pilots.”

Keeping this plane flying in the air requires significant research and development — and that starts with the battery. Namely, the Alice stores a 900kWh battery pack in its underbelly. “In terms of the size of the battery, it is an 8,000-pound battery,” says Davis. “That 8,000-pound battery is fairly similar to what a full fuel load on a plane that size might weigh,” Davis told InsideEVs. “It actually works out well inside the existing rules for aircraft sizing.”

The 900kWh battery pack gives the Alice a range of around 250 nautical miles (with an additional 30 minutes for reserves), meaning it’s geared strictly for short-distance travels.

[…]

We need to have a good battery life, but it doesn’t need to be a 20-year battery. What we’re actually doing is designing our battery to be a 3,000-cycle or 3,000-hour battery, and they’ll get replaced during routine maintenance. We make sure that you’re also operating in the top 10% of battery utilization.”

Interestingly, aircraft turbine engines need to be rebuilt around every 3,000 cycles, and after several rebuilds, they’ll need to be replaced entirely.

[…]

“For the aircraft, electricity that is derived from the grid is between 30 and 70% cheaper than aviation fuel, and that’s in today’s environment,” Davis told InsideEVs. Besides the fuel cost savings, electric motors providing thrust will be less maintenance intensive than a turbine engine. “The electric motors are so much less costly to maintain than a traditional turbine engine,” Davis said.

But ditching the turbines comes with an unexpected benefit. Namely, the plane won’t have to reach 30,000+ feet to achieve maximum efficiency.

[…]

The ability to fly lower also means that Alice won’t have to spend more time climbing, which is a highly energy-intensive task. Along with cutting down carbon emissions, the Alice will also reduce noise pollution, an adversary of residential communities located near airports. “One of the advantages of an electric aircraft is that it’s very quiet. It’s incredibly quiet, especially compared to a turbine aircraft,” Davis said. With the quieter flight, these planes might be allowed to fly into airports with curfews during off-hours, like John Wayne Airport (SNA) in Irvine, California.

“The idea is that with an {electric} aircraft, you can access the airport infrastructure at 2:00 in the morning to do an overnight package delivery,” Davis told InsideEVs. “That rapid point-to-point package delivery for the freight provider is {highly beneficial}. Being able to knock twelve hours off your delivery time is very valuable to freight companies.”

Comments

  1. Bruce Purcell says:

    I wonder what the weight of a generator and fuel would be.

  2. Gavin Longmuir says:

    Swings & roundabouts. Flying lower may be an advantage in an energy use sense, but it means the plane will be flying in the turbulent weather zone rather than the calmer air at 30,000 feet — buckle up and hold onto that air-sickness bag!

  3. McChuck says:

    Every plane has “the ability to fly lower.”

    Every plane can fly to an airport at 2:00 am.

    Next-night air is, in fact, not faster than same-day air.

    The 8,000 pound battery doesn’t get much lighter as you use it up, thus it doesn’t get more efficient in the latter half of the trip.

    I bet they can’t fly lower than a truck or a locomotive!

  4. Jim says:

    We’ll have room-temperature superconductors before we have lithium-ion batteries capable of supporting electric airplanes.

  5. VXXC says:

    This is a very expensive way to advance basic research but here we are…

  6. Phil B says:

    The random in-flight barbecue is not be touted as one of the benefits of the lithium battery in the press release.

  7. Bob Sykes says:

    Batteries have only one-tenth the energy content of an equal weight of fossil fuel, and Davis is flat out lying about it. He is also lying about the cost to charge the battery; it will be many times the cost of the fossil fuel it replaces.

    McChuck is right about the fuel burn. Planes get much lighter over their flight plans.

    This whole electric business yet another scam.

  8. Chris J. says:

    Now, where did I leave my 800V charging adapter…?

  9. TRX says:

    Besides the need to have a grid drop of sufficient amperage, charging still takes time. Commercial vehicles only make money when they’re moving.

    I wonder how long it would take to charge that 8-ton battery.

    Also, batteries are generally temperature-sensitive. A few hours sitting on a sunny runway, and you can burn your hand touching the plane. At 30,000 feet the ambient temperature is -70F.

  10. David Foster says:

    “a range of around 250 nautical miles (with an additional 30 minutes for reserves”..but normal reserve requirement for Instrument Flight Rules flights is 45 minutes. Surely they aren’t planning to restrict operations to Visual Flight Rules…

  11. VXXC says:

    I can predict with confidence that not much energy will be used in the climb, except perhaps of bank accounts, lawyers fees, possibly stock prices.

    The entire thing isn’t GREEN unless you bless away the vast amounts of BROWN to make it GREEN, which doesn’t address the 2,000 tons of waste for every ton of REE refined, including 1 ton of radioactive uranium or thorium waste left over.

    But not to worry, someday they’ll be posts on how the radioactive waste has been repurposed as [?], and, moreover, the future Princess Markle II can tour the world promising to clean up the glowing sludge leftover from GREEN.

    This scam ends when humanity ends, I suppose.

  12. Lucklucky says:

    It depends on speed. For example, an attack combat fighter jet has about 50% range at low level compared to its most economic altitude. There is more drag at low level.

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