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Electric aircraft set to take flight by 2026 under new agreements

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Re: Electric aircraft set to take flight by 2026 under new agreements

#141

Post by silvestrov »

holycrapwhodat wrote: post #126
gregmac wrote: post #108

Earlier quoted context omitted.

> Develop software that can fly the planes autonomously from strip to strip (I assume this is the really hard part, but I am under the impression that autonomous flying is a much easier problem than autonomous driving?). As a software developer, this part is what I don't like. We're still quite a ways from fully autonomous driving cars (as in: don't rely on a human taking over for backup). A bad bug in an autonomous…

As both a software developer and a pilot... We're (much?) closer to Fully-Self-Flying planes than FSD cars because the problem space is - perhaps counterintuitively - MUCH smaller to tackle. And we have a lot more experience tackling it. Additionally there could easily be remote pilots as backup in case of catastrophe (See remote piloted military and border patrol UAVs) And pulling a parachute at 1000'+ altitude actu…

> string of automated glider ports

There is a small precedent here: the space shuttle flew almost 100% by computers.

There was a small involvement of the pilots when landing and some change of software due to small RAM size in the computers.

I could imagine "Fully-Self-Flying planes" would start out with cargo planes between areas with low population.

Re: Electric aircraft set to take flight by 2026 under new agreements

#142

Post by otterley »

Tossrock wrote: post #138
tadfisher wrote: post #131

Earlier quoted context omitted.

Battery swaps could be viable, barring some complications in gate infrastructure and airframe design. Obviously this would be impossible if airframe designers incorporate battery cells in structural members, as some suggest to offset the weight penalty.

I've said for a while that electric planes are the perfect use case for aluminum-air batteries. Aluminum-air batteries have up to 8x the energy density of lithium ion, but are not rechargeable, so using them only makes sense if you have a system to recycle the used batteries. This doesn't make a ton of sense with cars, because cars are constantly going from random place to random place, and having to include a stop a…

What's the process for recycling an aluminum-air battery? And is it cost/energy effective to do so?

(If you think about it, closed-loop recycling of energy storage is just another form of recharging, but with extra steps.)

Re: Electric aircraft set to take flight by 2026 under new agreements

#144

Post by 908B64B197 »

gunapologist99 wrote: post #128

One of the things that helped Southwest dominate in the short-haul space, particularly in the Texas Triangle, was optimizing "turn-time" with a target of less than 10 minutes to both deplane and board passengers (10 minutes!)[0] I wonder how lengthy charge cycles will affect the viability of fast turn times, especially for the short-haul segments that they're targeting for these new airliners. It seems like they'll n…

If they use them to fly to and from tiny airports they might fly only a few times per day with enough time to recharge in-between (because there's no demand).

Since the planes themselves are really small, they also won't spend a long time at the gate so they could be transported to a maintenance hangar to recharge.

Re: Electric aircraft set to take flight by 2026 under new agreements

#145

Post by benhurmarcel »

topkai22 wrote: post #110
SonicScrub wrote: post #47

Earlier quoted context omitted.

The Youtuber Real-Engineering (aerospace engineering background) has a good video discussing the viability of electric aircraft. Barring some dramatic revolution in battery energy density, electric aircraft beyond a certain range are simply not-feasible. They are very feasible for short-range routes though. https://www.youtube.com/watch?v=VNvzZfsC13o

I think the caveat here is "battery powered electric aircraft." Fuel cells have much higher energy density IIRC. It's not inconceivable that fuel cell electric planes could become a thing as well, especially if these early BEV show other benefits around maintainability, noise reduction, etc. I think its a long shot though, as jet fuel + carbon capture will probably be price competitive before fuel cell airliners beco…

Fuel cell aircraft are very much a thing, and are being researched by the biggest companies in the industry.

But they’d be called hydrogen aircraft rather than electric by most people.

Re: Electric aircraft set to take flight by 2026 under new agreements

#146

Post by Infernal »

otterley wrote: post #142
Tossrock wrote: post #138

Earlier quoted context omitted.

I've said for a while that electric planes are the perfect use case for aluminum-air batteries. Aluminum-air batteries have up to 8x the energy density of lithium ion, but are not rechargeable, so using them only makes sense if you have a system to recycle the used batteries. This doesn't make a ton of sense with cars, because cars are constantly going from random place to random place, and having to include a stop a…

What's the process for recycling an aluminum-air battery? And is it cost/energy effective to do so? (If you think about it, closed-loop recycling of energy storage is just another form of recharging, but with extra steps.)

From wikipedia[0] "it is possible to mechanically recharge the battery with new aluminium anodes made from recycling the hydrated aluminium oxide". I've found a few papers regarding recovery of aluminum from aluminum oxides, but I don't have the background to interpret them with an eye towards that process's impact on the overall efficiency of the battery.

[0] https://en.wikipedia.org/wiki/Aluminium–air_battery

Re: Electric aircraft set to take flight by 2026 under new agreements

#147

Post by aerospace_guy »

dogman144 wrote: post #97
karagenit wrote: post #67

Earlier quoted context omitted.

I think what they're trying to say is that the types of electric motors used in vehicles (like switched reluctance motors[1]) typically require a computerized controller that someone has to program, and therefore has an additional point of failure from a software standpoint. However, I'm pretty sure any modern internal combustion engine will have a highly advanced ECU computer too, so this is sort of a non-issue (tho…

Ya poorly worded on my part. Gist is going from internal combustion with a ton of supporting or fully necessary tech to fully electric, fully SW-driven, really skeeves me out given the above testimonial and others like it. I openly allow it's quite possible that airplanes can't fly these days but for software though.

Modern turbofan/turbojet/turboprop (really, any engine) has a ton of SW involved. Engine controllers [1] literally control the engines. Your point is completely wrong, I've worked on this software and they go through many forms of verification for things to work. Look at the failure rate of avionics and compare that to other industries.

Sure you or your friend may have had a bad experience at that company, but the big players generally won't let software bugs through.

[1] https://en.wikipedia.org/wiki/FADEC

Re: Electric aircraft set to take flight by 2026 under new agreements

#148

Post by kaba0 »

gamegoblin wrote: post #99

I recently had a pie-in-the-sky business idea and I would love for someone who knows more about the industry why it will definitely fail. I assume it's unworkable for a lot of reasons, but it is just plausible enough to be a fun idea for a sci-fi novel. Get a fleet of 2-4 seater unpowered glider planes [1] Get a bunch of rural properties spaced ~100km apart. Put little glider landing and launch strips on each propert…

Other than the already mentioned parts, wouldn’t the acceleration be too great for your average passenger?

Re: Electric aircraft set to take flight by 2026 under new agreements

#149

Post by gamegoblin »

kaba0 wrote: post #148
gamegoblin wrote: post #99

I recently had a pie-in-the-sky business idea and I would love for someone who knows more about the industry why it will definitely fail. I assume it's unworkable for a lot of reasons, but it is just plausible enough to be a fun idea for a sci-fi novel. Get a fleet of 2-4 seater unpowered glider planes [1] Get a bunch of rural properties spaced ~100km apart. Put little glider landing and launch strips on each propert…

Other than the already mentioned parts, wouldn’t the acceleration be too great for your average passenger?

On a 1km runway you could get up to 700kph with 3g of acceleration over 10 seconds. I think some rollercoasters pull higher G's than that.

Re: Electric aircraft set to take flight by 2026 under new agreements

#150

Post by tgsovlerkhgsel »

hutzlibu wrote: post #134
tadfisher wrote: post #131

Earlier quoted context omitted.

Battery swaps could be viable, barring some complications in gate infrastructure and airframe design. Obviously this would be impossible if airframe designers incorporate battery cells in structural members, as some suggest to offset the weight penalty.

"Obviously this would be impossible if airframe designers incorporate battery cells in structural members, as some suggest to offset the weight penalty." Why not do both? Swap one part and charge just the internal batteries. But internal batteries does not sound so clever with limited lifetime anyway.

Charging is limited by two factors:

- the power you can get from the charger to the batteries - the power the cells can accept

You can reasonably easily fix the first point with custom infrastructure, so the second point will be the limiting factor, and that one means that it always takes e.g. 20 minutes to charge your batteries, regardless how many you're charging (because with a bigger battery, you're simply charging more cells in parallel, at the same speed per cell).

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