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Transportation

United and Mesa To Buy Electric Planes For Short Trips (wsj.com) 42

Posted by BeauHD from the aircraft-of-the-future dept.
United and a regional airline partner are hoping to use a new electric plane to revitalize short-haul flying. The Wall Street Journal reports: United's venture fund and Mesa Air Group Inc. are investing in Heart Aerospace, a Swedish company developing a 19-seat electric aircraft. Tuesday's deal is the latest in a series of bets on new aircraft concepts yet to be tested but that United said could help it reduce carbon emissions. Each airline has agreed to order 100 of the planes, once they have been built, as long as the final product meets the airlines' specifications.

United and Mesa have previously announced plans to invest in Archer Aviation, a Palo Alto, Calif.-based company that is developing an electric flying taxi, and to purchase as many as 200 of those aircraft. United has also announced plans to buy 15 new supersonic jetliners being developed by Boom Technology Inc. None of these new aircraft have flown yet, and it will be years before any of them carry passengers. The companies said they expect the new plane, known as the ES-19, to begin service by 2026.
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United and Mesa To Buy Electric Planes For Short Trips More

United and Mesa To Buy Electric Planes For Short Trips

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  • Regenerative braking (Score:4, Informative)

    by mkwan ( 2589113 ) on Wednesday July 14, 2021 @07:05PM (#61583447)

    One nice thing about electric planes is that they can recover some of the energy lost during the descent phase, by turning their propellers into generators on the way down.

    • Re:Regenerative braking (Score:5, Insightful)

      by WoodstockJeff ( 568111 ) on Wednesday July 14, 2021 @09:22PM (#61583579) Homepage

      Assuming your aim is to descend VERY VERY QUICKLY.

      Propellers and ducted fans make very effective air brakes when being spun by the air stream instead of a power source

      • It can be adjusted to the desires of the pilot, of course. Getting down quicker is useful in many scenarios. I'm specifically interested in skydiving operation, where almost all of the time is spent climbing or descending.

      • Re: (Score:2)

        by AmiMoJo ( 196126 )

        Some aircraft use a ram-air turbine to generate emergency power if the main jet engines fail. They are low drag devices so they don't cause the aircraft to lose too much speed.

        Potentially a propeller could be used for the same thing if it were designed with that in mind.

      • Re: (Score:1, Troll)

        by rtb61 ( 674572 )

        Clearly a person who does not understand where lift comes from, the plane moving through the air. It takes energy, if you suck out any of that energy, the plan will immediately lose lift and not fly that well. The plane will readily slow right down, just trying to maintain altitude the dive, yeah passengers do not live diving, climbing or turning, they want to feel nothing. The plane flies to the landing is does not dive, a smooth gentle controlled descent.

        What they need for short hauls is very efficient

    • In theory.
      In praxis not.

      You are required to land with enough propulsion that you can do a very short take off again, in case something unexpected happens, e.g. missing the landing spot, slippery runway, something you could collide with etc.

      Most planes do not even allow reverse power if not minimum two wheels touch the ground.

      • That's mostly a limitation of today's engines and reverse power systems though. A turbine needs several seconds to go from idle to full power, even in an emergency, and a reverse thrust diverter moves even more slowly. Electric motors and controllers can be designed to go from regen to full power in a split second.

        • I had a conversation with a Boeing 707 pilot once where he said that on descent he would (or at least could, as in this was not restricted by the mechanical properties of the plane or by operating procedure) put the inner two engines on reverse thrust. If there was a need to abort takeoff the process of pushing the throttles forward would disable reverse thrust and increase power in one motion. It would believe it not be too much speculation to think that the delay in increased thrust would be enough for

          • Meanwhile, the Pipistrel Alpha Electro already uses regen with good effect: "Alpha Electro is a 2-seat electric trainer with performance which is tailored to the needs of flight schools. It has short take-off distance, powerful 1000+ fpm climb capability and an endurance of one hour plus a 30-minute reserve. The Alpha Electro is optimized for traffic-pattern operations, where up to 13% of energy is recuperated on every approach, increasing operations range and at the same time enabling short-field landings.

    • While potentially a good idea on the surface (no pun intended), recouping energy at the end of a flight isn't going to be much of a boon. There's plenty of electricity available on the ground - the plane needs it available for long periods of time up in the sky.

  • We all know jet engines are really loud.

    Show does the decibel level of a motor that powers propellers large enough to fly a plane compareI wonder? Is it going to be quieter, or some much larger version of that drone whine we all know...

    • Re: Noise levels - worse or better? (Score:4, Informative)

      by Åke Malmgren ( 3402337 ) on Wednesday July 14, 2021 @11:54PM (#61583783)
      They won't be silent, but they'll be a bit quieter than turboprops and a lot quieter than piston engine aircraft. If traditional propellers are deemed too noisy still, added blades or ducted fans can reduce it further.
      When MagniX filmed a trial of an e-Caravan conversion, its sound was completely drowned out by another piston caravan flying much higher. They specifically hope that e-aviation can revitalize small airports where noise concerns so far have made commercial traffic impractical.

      • Great, I was hoping it was something along those lines where there was noise mitigation for small airports.

      • a bit quieter than turboprops and a lot quieter than piston engine aircraft

        Tu-95 laughs at your implication of the relative loudness of the two.

        • I'll see your Tu-95 and raise you a XF-84H
        • You don't need a super large plane to make this point. Literally every turbo prop (or just plain jet) that I've heard on a general aviation ramp is *much* louder than basically every other piston plane.
          • My references are small Cessnas, mainly 206 and 207, and the turbine conversions on those are quieter than the piston engines.
            • Maybe just at full power? A 182 taxiing I can tell you from personal experience is way way quieter than a Pilatus for example. Those things are basically jets.
              • A pilatus is much bigger than a C182 though. My experience is mostly with small skydiving planes, especially C206, of which I've ridden pistons (loud) turbocharged (really loud) and turboprop ( not that loud). If your experience is of general aviation, you'd probably get a different picture since the bigger propeller planes tend to be turboprops, and the smaller ones piston engined.

    • Definitely much quieter during idle and flight.
      I fly regularly https://www.intelligent-aerosp... [intelligen...ospace.com]
      While they are still noisy, the sound of the propellers is more pleasant than jet engines. Think about motorbike versus car with an ugly sound.

    • Most people don't seem to realize that a lot of the noise from jet/prop planes helicopters and leaf blowers come from the "fan" itself. Just listen to how obnoxious a toy electric drone can be with it's 4 6" diameter blades. Things like electric leaf blowers are quieter simply because they're so woefully underpowered compared to their gas brethren that they move significantly less air, hence less noise
      • The noxious and obnoxious two-stroke engine of a gasoline-powered leaf blower contributes a lot to theis noise, and drones have no noise mitigation whatsoever. That being said, moving a lot of air very fast won't be silent - but it will be much nicer.

    • Re: (Score:2)

      by necro81 ( 917438 )

      does the decibel level of a motor that powers propellers large enough to fly a plane compareI wonder? Is it going to be quieter, or some much larger version of that drone whine we all know

      To answer, consider a thought experiment: let's assume for a moment that the air-moving features (the props/blades/fans) are identical, and all we're doing is changing the source of mechanical power. Electric motors can run almost silently, whereas a piston engine or turbine is a series of controlled explosions. How do

    • We all know jet engines are really loud.

      I question that statement. 1960's and 70's jet engines were certainly very loud. However, modern aircraft use turbofans, and are much quieter. My office is near a major airport, and every once and a while I'll hear an older jet take off. There is a dramatic difference in noise. I've also noticed a dramatic change in helicopter noise over the past 30 years as well.

      I suspect these electric aircraft will sound a lot like my neighbor's electric lawn mower. It's much quieter than a gasoline powered mower.

      • I question that statement. 1960's and 70's jet engines were certainly very loud. However, modern aircraft use turbofans, and are much quieter.

        I found data! Slide 2 of this presentation. [ucdavis.edu] The area subjected to 85dB noise is dramatically reduced between a 737 MAX versus the ancient 737-200 aircraft that used a low bypass engine design. [wikipedia.org]

        As with many things. I suspect when people talk about being, "as loud as a jet engine," they are referencing the 1960s. The US, as a nation, is stuck on the notion that things have only gotten worse from that point in time. When in fact, things have gotten much much better, but so slowly, it's difficult to noti

  • Point to Point Starships in a fifth the time a supersonic would do it.

    • E-planes will start out flying small hops. They don't compete for the same routes. Maybe you'll even e-hop to the Starship sea launch platform in a small seaplane.
    • More than intercontinental. The rate they're moving, I'm sure there will also be semi regular flights to the moon if not Mars by then. They've gone from pretty much nothing to what they are today in about a decade. They don't have to reinvent the wheel this go around, just think how much farther they'll be in half a decade. Aside from making a rocket work they had to build out tons of manufacturing infrastructure, hire up engineers. They now have that infrastructure and engineers from falcon that can be qui

      • I doubt we'll be seeing routine passenger flights to either by 2026. Maybe, MAYBE, some passenger travel to the moon by then, but not routine. Mars, I would expect we'll be seeing semi-routine (based on proximity of the planets) cargo loads being taken to Mars and perhaps sample returns on the ships coming back for more cargo. I'm extremely skeptical we'll have passenger flights to Mars on anything resembling a routine basis by 2026.

        SpaceX at this point has done some amazing things, and I look forward to

  • While fuel costs typically represent the largest single cost in running a commercial air service, the second largest cost is often maintenance. The rising cost of fossil fuels means that electric aircraft have the potential for cheaper fuel costs but the huge reduction in the complexity of the engines stands the deliver big operational savings right now. Proponents of jets and turbine engines like to say that they "only have one moving part", when comparing them to reciprocating piston engines, but look und

    • Re: (Score:2)

      by nickovs ( 115935 )
      By way of validation that they have a lot fewer moving parts, see Heart Aerospace's FAQ [heartaerospace.com] talking about the economics of their engines:

      Our electric motor is about 20 times less expensive than a similarly-size turboprop, and about a 100 times less expensive than the cheapest turbofan. More importantly, maintenance costs are more than 100 times lower.

      That's a real saving!

    • Re: (Score:3)

      by cusco ( 717999 )

      Harbour Air is converting its fleet to electric for about the same cost as the regular 2,000 hour engine overhaul.

      https://spectrum.ieee.org/ener... [ieee.org]

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