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First all-electric seaplane takes flight in B.C.

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Re: First all-electric seaplane takes flight in B.C.

#71

Post by jsjohnst »

netrap wrote: post #63
jsjohnst wrote: post #54

Earlier quoted context omitted.

The idea that a lightning bolt could be used as a power up source has been thoroughly debunked by myself and others in this thread already, but I thought I’d take another angle in response, just using electricity in general. A single GE90 aircraft jet engine used in the 777 is up to 111,000 horsepower[0]. So for the Boeing 777, that’s ~220,000HP. Converting horsepower to megawatts, that’s 164MW of power during takeof…

Are planes using all that HP? Isn't HP flexible? That's the point of say a car dyno, right?

A fully loaded commercial jet is usually at or close enough to max engine power at takeoff. During flight, estimates I’ve seen online are around 50% of the maximum jet engine HP.

Re: First all-electric seaplane takes flight in B.C.

#72

Post by jacquesm »

riazrizvi wrote: post #61
semi-extrinsic wrote: post #27

You can do small aircraft like this, no problem. The trouble is you can't scale it up, due to how quickly the power and energy demands go up. This thing is 560 kW and gets a range of 86 nmi; an A320 is around 40 000 kW and has a range of 3 500 nmi, while an A380 is around 80 000 kW and has a range of 8 500 nmi. Going from this DHC-2 to the A380 requires an increase in energy storage by a factor of around 14 000x, whi…

According to my numbers an electric 747 would get more people further. 1. DHC-2 takes 6 people 86 miles ~= 500person/miles 2. 747 potential battery payload ~= 200,000kg (fuel capacity) 3. Power capacity of 200,000kg lithium-in ~= 25MW hours 4. Power required to take off, assuming 2.5 minutes to reach cruising altitude ~= 90MW * 2.5 / 60 ~= 4MWh 5. Power to cruise at about 600mph ~= 1/4 power to take off = 22MW (waves…

It takes a 747 quite a bit more than 2.5 minutes to reach cruising altitude. 30,000 ft at 5000 fpm is 6 minutes, and engine input is a lot higher than 90 MW because engines are not even close to 100% efficient (neither are electrical ones).

Also, the weight on landing is critical not on takeoff, and you can't exactly shed battery weight because empty batteries weigh roughly the same as full ones do, so you will need to take maximum landing weight into account.

Finally, you need to take reserve fuel into account, alternates and headwinds.

I think you should re-do these numbers with more realistic inputs.

Re: First all-electric seaplane takes flight in B.C.

#73

Post by Robotbeat »

deepspace wrote: post #47
semi-extrinsic wrote: post #27

You can do small aircraft like this, no problem. The trouble is you can't scale it up, due to how quickly the power and energy demands go up. This thing is 560 kW and gets a range of 86 nmi; an A320 is around 40 000 kW and has a range of 3 500 nmi, while an A380 is around 80 000 kW and has a range of 8 500 nmi. Going from this DHC-2 to the A380 requires an increase in energy storage by a factor of around 14 000x, whi…

> This thing is 560 kW and gets a range of 86 nmi Not even that. I believe an 86 nmi range is what they are hoping to achieve by 2025. Current range is a fraction of that. The technology demonstrator has a theoretical flight time of 15 minutes and no ability to carry passengers because all the room/weight is taken up by batteries.

30 minute flight time, not 15. Should have approximately 86 mile range with this one.

There's plenty of room for passengers in this concept. Where are you getting this false information?

Re: First all-electric seaplane takes flight in B.C.

#74

Post by manigandham »

semi-extrinsic wrote: post #27

You can do small aircraft like this, no problem. The trouble is you can't scale it up, due to how quickly the power and energy demands go up. This thing is 560 kW and gets a range of 86 nmi; an A320 is around 40 000 kW and has a range of 3 500 nmi, while an A380 is around 80 000 kW and has a range of 8 500 nmi. Going from this DHC-2 to the A380 requires an increase in energy storage by a factor of around 14 000x, whi…

Also batteries weigh the same at landing and takeoff while jets rely on the reduced weight from fuel burn for safe landing.

Re: First all-electric seaplane takes flight in B.C.

#75

Post by riazrizvi »

jacquesm wrote: post #72
riazrizvi wrote: post #61

Earlier quoted context omitted.

According to my numbers an electric 747 would get more people further. 1. DHC-2 takes 6 people 86 miles ~= 500person/miles 2. 747 potential battery payload ~= 200,000kg (fuel capacity) 3. Power capacity of 200,000kg lithium-in ~= 25MW hours 4. Power required to take off, assuming 2.5 minutes to reach cruising altitude ~= 90MW * 2.5 / 60 ~= 4MWh 5. Power to cruise at about 600mph ~= 1/4 power to take off = 22MW (waves…

It takes a 747 quite a bit more than 2.5 minutes to reach cruising altitude. 30,000 ft at 5000 fpm is 6 minutes, and engine input is a lot higher than 90 MW because engines are not even close to 100% efficient (neither are electrical ones). Also, the weight on landing is critical not on takeoff, and you can't exactly shed battery weight because empty batteries weigh roughly the same as full ones do, so you will need…

Reserve fuel? I didn’t even allocate any fuel to land, I am assuming passengers won’t mind the bumps at their destination, you know for the planet.

Re: First all-electric seaplane takes flight in B.C.

#76

Post by deepspace »

Robotbeat wrote: post #73
deepspace wrote: post #47

Earlier quoted context omitted.

> This thing is 560 kW and gets a range of 86 nmi Not even that. I believe an 86 nmi range is what they are hoping to achieve by 2025. Current range is a fraction of that. The technology demonstrator has a theoretical flight time of 15 minutes and no ability to carry passengers because all the room/weight is taken up by batteries.

30 minute flight time, not 15. Should have approximately 86 mile range with this one. There's plenty of room for passengers in this concept. Where are you getting this false information?

See: https://www.skiesmag.com/news/harbour-air-makes-history-with...

From the article:

> What certainly hasn’t been done before is to fill a Beaver’s cabin with lithium-ion batteries, taking the plane to its gross weight. As a technology demonstrator, this eBeaver isn’t carrying passengers — there isn’t room — and will only have a 15-minute endurance with a 25-minute reserve.

Re: First all-electric seaplane takes flight in B.C.

#77

Post by ct0 »

Robotbeat wrote: post #73
deepspace wrote: post #47

Earlier quoted context omitted.

> This thing is 560 kW and gets a range of 86 nmi Not even that. I believe an 86 nmi range is what they are hoping to achieve by 2025. Current range is a fraction of that. The technology demonstrator has a theoretical flight time of 15 minutes and no ability to carry passengers because all the room/weight is taken up by batteries.

30 minute flight time, not 15. Should have approximately 86 mile range with this one. There's plenty of room for passengers in this concept. Where are you getting this false information?

Imagine the headaches when the airport tells these guys to hover for a while wile delays clear out. This is a niche product, albeit a cool one.

Re: First all-electric seaplane takes flight in B.C.

#79

Post by Robotbeat »

semi-extrinsic wrote: post #27

You can do small aircraft like this, no problem. The trouble is you can't scale it up, due to how quickly the power and energy demands go up. This thing is 560 kW and gets a range of 86 nmi; an A320 is around 40 000 kW and has a range of 3 500 nmi, while an A380 is around 80 000 kW and has a range of 8 500 nmi. Going from this DHC-2 to the A380 requires an increase in energy storage by a factor of around 14 000x, whi…

This is not true. It's easier to scale up. You get more efficient.

Scaling up an electric motor is not particularly hard. Some of the largest machines in existence are electric.

Power is not a challenge for electric. In fact, this electrified seaplane has much more power (560kW) than the original radial piston engine one (336kW), and even more than the turboprop conversion (510kW).

A LOT of very confident people on the Internet post lots of very wrong and/or outdated misinformation about electric aircraft (and electric vehicles in general).

Energy is a challenge, but the answer there is to increase efficiency and increase the mass of the vehicle which is battery. Both of those together give you a usable range of about 1000km. The same motor provider, Magnix, is also providing the motors for the 1000km range Eviation Alice.

Just because a conventional aircraft maker thinks something isn't possible, doesn't mean someone can't make it work. It most certainly doesn't require 30 times the energy density. For the same exact reason why electric cars don't require batteries with 30 times the energy density to compete with gasoline cars.

Re: First all-electric seaplane takes flight in B.C.

#80

Post by nbrempel »

CalChris wrote: post #13
jascii wrote: post #2

The title is a little misleading: This is not a commercial flight, currently the plane in question is licensed by the FAA as "experimental" specifically excluding commercial flights. Still cool! I think electric might have a great future in short-hop flights.

Licensed by the FAA in Canada?

I believe the FAA and TCCA have a bilateral agreement so it very well could be the FAA.

https://www.faa.gov/aircraft/air_cert/international/bilatera...

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