World's first all-electric commercial plane set for takeoff in Richmond

[MechAg94]

https://www.cbc.ca/amp/1.5378163?__twitter_impression=true

Vancouver-based Harbour Air is getting set for its own version of Kittyhawk on Dec. 11 when founder and CEO Greg McDougall takes to the skies over Richmond for the inaugural test flight of the world's first fully electric commercial aircraft.
----------------
McDougall will be flying solo in a DHC-2 de Havilland Beaver float plane that has been retrofitted with a 750 horsepower electric motor.

"We already know the electric propulsion system works," said McDougall. "What that aircraft will be pioneering is the regulatory framework to actually be able to carry passengers on electrified flight. Nobody's done that before."

I think they are just doing a 10 minute flight and trying to get certified for commercial use.  It sounds like they don't intend to actually use it commercially.

I also guess the new trend is that anything that doesn't burn oil based fuel gets an "e" on the front and is considered good for the environment.  They could be made of arsenic and trail a cloud of mercury vapor, but as long as it doesn't burn gas, it is great.

[230RN]

Heh.  Inflight recharging?  

    

But I'm constantly in awe about the energy density of modern power cells.  Where do they fit all them 'lectrons anyhow?

[griz]

Sounds more like a press release than a report.  We'll see.  Batteries are heavy, and that matters a lot in the air.

[dogmush]

Sounds more like a press release than a report.  We'll see.  Batteries are heavy, and that matters a lot in the air.

To put numbers on that statement:

Gasoline has an energy density of 44 MJ/Kg.  Li Ion Batteries have an Energy Density of about 1 MJ/Kg.  True, batteries can be recharged while fuel is burned once and gone, but that's a steep difference. 

I'd have to do a LOT more math, but perhaps there's a use case for short hops, where the 44x reduction in range (from the same weight fuel) is offset by the cheap "refueling" but I doubt it.  As Fuel gets more expensive though, that might change.

[230RN]

Sounds more like a press release than a report.  We'll see.  Batteries are heavy, and that matters a lot in the air.

I also wondered about the Fe weight of a 750 HP electric motor.  Did someone invent magnetic aluminum during my 3PM nap?

[230RN]

Did they use photovoltaics to help the batteries?

https://en.wikipedia.org/wiki/Helios_Prototype

[Ben]

Did they use photovoltaics to help the batteries?

https://en.wikipedia.org/wiki/Helios_Prototype

That can help with light aircraft and lightweight payloads. The small RQ-20 drones I used to fly (made by the same guys who did the Helix for NASA) started using solar wings just before I retired. The standard flight time on batteries back then was two hours. Initial testing of the solar wings upped that to ~10 hours if you didn't go crazy on speed under ideal conditions. That was back in 2013 -  I don't know what current times might be with solar and battery improvements.

Of course that's around 14lbs with payload/instrumentation, with lots of wing surface for solar panels, and even then, the battery was probably close 1/3 of the weight.

[Fly320s]

I also wondered about the Fe weight of a 750 HP electric motor.  Did someone invent magnetic aluminum during my 3PM nap?

I wonder why they went with a 750hp motor.  The original motor was 450hp.

[lee n. field]

Batteries are heavy, and that matters a lot in the air.

Batteries are heavy, and they don't get lighter as you use up the 'lectricity.

[230RN]

I wonder why they went with a 750hp motor.  The original motor was 450hp.

Reading that, I thought I might have misread the number, but from OP's quote:

Quote

McDougall will be flying solo in a DHC-2 de Havilland Beaver float plane that has been retrofitted with a 750 horsepower electric motor.

I can't answer why they used a 750 HP motor.  Compensate for battery weight?

Kinda odd.  Seems to me subbing a 750 HP (559,500 Watts) electric motor can't possibly be "better" ecologically than a 450 HP (335,700 Watts) engine.

Watts is Watts.

Maybe MechAg94 is right:

I also guess the new trend is that anything that doesn't burn oil based fuel gets an "e" on the front and is considered good for the environment.  They could be made of arsenic and trail a cloud of mercury vapor, but as long as it doesn't burn gas, it is great.

Ecology Theater.  Like Security Theater.

Terry, 230RN

[zahc]

Motor wattage is not a big efficiency difference if it's not much heavier.

Usually fuel economy on short trips is impacted a lot by how fast the plane can climb up out of dense air and get into thinner cruising altitude. That's probably why they went bigger.

[Hawkmoon]

It looks like their commercial flights are either sightseeing tours, or very short hops between nearby cities around Puget Sound and the Straits of Juan deFuca, so I doubt that there's much likelihood of climbing into less dense air.

[tokugawa]

A Beaver? Seriously? The only possible reason to pick a Beaver is load capacity for the batteries- Beavers are low and slow and the king of drag.
Essentially, a pickup truck of the sky.

[dogmush]

A Beaver? Seriously? The only possible reason to pick a Beaver is load capacity for the batteries- Beavers are low and slow and the king of drag.
Essentially, a pickup truck of the sky.

Well, they could have picked an AN-2.   

[230RN]

I'm told that an AN-2 is practically its own parachute.

Or so I'm told.

Thirty-one mph stall speed listed in the specs.

But I guess Beavers are more available.

[Fly320s]

Well, they could have picked an AN-2.   

Or a Wilga.  Maybe give Mike Patey a run for his money in the STOL drags.

Mike's "slightly modified" Wilga, Draco.  https://www.youtube.com/watch?v=QyxnWz7eJv0    Skip to 6:30 for the money shot.

[230RN]

Batteries are heavy, and they don't get lighter as you use up the 'lectricity.

Well, they do, by E ÷ c².

Measure it.  You'll see.

Terry grabs his high-speed cane and hobbles away at a great rate.

[HankB]

. . . True, batteries can be recharged while fuel is burned once and gone, but that's a steep difference . . .

And fuel tanks can be refilled . . . and yes, in-flight refueling is possible.   

[Tim L]

Probably could have accomplished the same thing with a Piper Cub and a Tesla battery pack and engine.

[Hawkmoon]

Or a Wilga.  Maybe give Mike Patey a run for his money in the STOL drags.

Mike's "slightly modified" Wilga, Draco.  https://www.youtube.com/watch?v=QyxnWz7eJv0    Skip to 6:30 for the money shot.

Mike "modified" Draco some more in September. It's "done" now ...

https://www.youtube.com/watch?v=pJmtTNqXB64

Draco was totaled. I believe he plans to rebuild it, but not the same as it was before.

[Fly320s]

Mike "modified" Draco some more in September. It's "done" now ...

https://www.youtube.com/watch?v=pJmtTNqXB64

Draco was totaled. I believe he plans to rebuild it, but not the same as it was before.

Yeah, he will.  Right now he is working on "Scrappy."   It is a Carbon Cub that will be highly modified.  He is hanging a 500hp 8 cylinder on the front attached to a monster four blade prop.  I think Mike qualifies as a Mad Engineer.

[Fly320s]

This is the prop: https://www.youtube.com/watch?v=stkvTQ1lCSw

Skip to 15:00 for the prop reveal.

[230RN]

Detailed weather explanation of the Draco crackup:

https://youtu.be/lqnp08N4qWg (5:02)

Apparently caused by crosswinds from an approaching front as they were taking off.  They were trying to get out of Reno before the oncoming front actually arrived.

Interesting that they were only there for a static display since the insurance if they were to actually participate in the flying would have been prohibitive.  Not amusing, just interesting.

Terry, groundlubber

[AJ Dual]

Well, they do, by E ÷ c².

Measure it.  You'll see.

Terry grabs his high-speed cane and hobbles away at a great rate.

Tis true. 

Article doesn't say but assume they've got a 20kWh battery capacity just for a round number. Similar to what an electric car might have.

Multiply by 1000 then 3600 to get the joules. So 72 million joules.

72 million joules divided by the speed of light squared (in M/s) . Or 72,000,000 / 8.988004e16 = 8.010677342822722e-10kg  there's no scale sensitive enough to measure the difference. Dust, fingerprints from picking up the batteries to put them on the scale, and random molecules the battery will shed from it's case, and random outgassing from the electrolyte will swallow the difference by orders of magnitude.

This assumes the energy use/conversion is 100%, but with resistance and heat losses in the plane's electrical distribution system and the motor, one can assume it's mostly 100% even if it's not going into propelling the plane.

[230RN]

But still, there's that 0.0000000008010677342822722 kg.

And it all goes to heat anyhow, one route or another.  Friction with the road, flexing of the tires, air slipping over the vehicle / aircraft.

I'm not signing this one so nobody will know I hobbled back into town.