Electric powered commercial aircraft -- here we go!
Moderator
A new airframe and engine combination should require some new certification shouldn't it?
In my discussions with Transport Canada Aircraft Certification Branch, they expressed an eagerness to participate in new design standards, as they recognize the need. There are other international authorities also working to develop new and appropriate design standards for electric planes. In my detailed review, I found that on the whole, certification of an electric plane becomes less burdensome than for an engine driven plane, when the requirements for ignition engines are no longer required. It is certain that this will be accomplished, it's just a matter of time. Harbour Air is obviously involved in that process, and good for them investing back into a new and important industry. Lots of development is required, and it has to start somewhere!
It'll be a Supplemental Type Certificate (STC). Commonly used for aircraft modifications - some more major than others. While some STC projects are done via DER approvals, I'm guessing that for a completely new powerplant installation the local regulatory office would be involved (maybe even some involvement from the national level due to the novel aspect of the change and it's high profile).
Somebody from ha can correct me, but word on the street is full charge out of Vancouver, a quick top up in Victoria. Then back to Vancouver for a QC battery swap with a fully charged battery
A battery swap? Changing 1000kg worth of battery on a float plane... that's going to be a fun exercise! 
Someone above mentioned "range" and "endurance"... I saw a claim in a story that they were expecting 30 mins flight + 30 mins reserve.
Kudos to them for giving it a go... hopefully it will help advance battery technology.
Someone above mentioned "range" and "endurance"... I saw a claim in a story that they were expecting 30 mins flight + 30 mins reserve.
Originally Posted by https://www.bloomberg.com/news/articles/2019-03-26/canada-seaplane-operator-harbour-air-plans-electric-engine-flight
Batteries remain the limiting factor for electrical propulsion in aviation, said Roei Ganzarski, MagniX’s CEO and a former Boeing executive. The Magni500 electric motor to be used in the Harbour Air flight testing is rated for 750 horsepower and offers a 60-minute range, more than twice as long as Harbour’s average flight, Ganzarski said, allowing for a 30-minute reserve on the batteries.
A great start for electric power, but surely simple physics limits what can be achieved unless someone invents an entirely new kind of battery.
For example, the specific energy of avgas and jet fuel is about 43 MJ/kg. The best lithium-ion batteries top out at about 0.9 MJ/kg (the batteries in a Tesla are about 0.7 MJ/kg), so they have a fraction of the storage of liquid fuels. The best battery technology in theoretical development (Lithium-air) has a theoretical maximum of 41 MJ/kg, more realistically they'll get 1/4 to 1/3 of that from the technology.
For example, the specific energy of avgas and jet fuel is about 43 MJ/kg. The best lithium-ion batteries top out at about 0.9 MJ/kg (the batteries in a Tesla are about 0.7 MJ/kg), so they have a fraction of the storage of liquid fuels. The best battery technology in theoretical development (Lithium-air) has a theoretical maximum of 41 MJ/kg, more realistically they'll get 1/4 to 1/3 of that from the technology.
Join Date: Jan 2017
Location: Warwick
Posts: 197
Likes: 0
Received 0 Likes
on
0 Posts
The key is energy density, the laws of physics don’t change, it takes exactly the same energy for a given weight and speed regardless of power source. The company projections are over optimistic if they expect 30 mins + 30 reserve with current technology, the experience with cars is that battery capacity and range achieved is very variable and a large margin has to be allowed. Range anxiety is a constant issue and will be critical in an aircraft.
A great start for electric power, but surely simple physics limits what can be achieved unless someone invents an entirely new kind of battery.
For example, the specific energy of avgas and jet fuel is about 43 MJ/kg. The best lithium-ion batteries top out at about 0.9 MJ/kg (the batteries in a Tesla are about 0.7 MJ/kg), so they have a fraction of the storage of liquid fuels. The best battery technology in theoretical development (Lithium-air) has a theoretical maximum of 41 MJ/kg, more realistically they'll get 1/4 to 1/3 of that from the technology.
For example, the specific energy of avgas and jet fuel is about 43 MJ/kg. The best lithium-ion batteries top out at about 0.9 MJ/kg (the batteries in a Tesla are about 0.7 MJ/kg), so they have a fraction of the storage of liquid fuels. The best battery technology in theoretical development (Lithium-air) has a theoretical maximum of 41 MJ/kg, more realistically they'll get 1/4 to 1/3 of that from the technology.
"Mildly" Eccentric Stardriver
The Wrights managed 120', and look at where we are now. These guys are starting the practical ball rolling, and I for one wish them every success.
Both nonsense and Herod make very good points and clearly Rolls Royce think electric aircraft have a promising future too. In highighting the energy density issue, I was merely trying to make sure readers understood one of the main obstacles to progress in this field. I think we should all wish them success.
https://www.rolls-royce.com/media/ou...ing-accel.aspx
https://www.rolls-royce.com/media/ou...ing-accel.aspx
Join Date: Jul 2007
Location: Auckland, NZ
Age: 79
Posts: 721
Likes: 0
Received 0 Likes
on
0 Posts
As I live in New Zealand, I am not well-disposed to "flight-shaming" (I'd love to be able to catch a train to Sydney), but sight-seeing flights, and short commuter flights when ground alternatives are available, are the sort of elective activities that we might all cut down on. So, climate neutral gives the joy-flight industry a great selling point.
Join Date: Jul 2003
Location: Canada
Posts: 257
Likes: 0
Received 0 Likes
on
0 Posts
No worse than with a petrol engine, I would imagine. My old Beech C23 glided like an anvil. I doubt a Beaver would be much worse! The longest flight is around 50 n.m. most of it over protected waters, so a water landing should be feasible in the event of engine failure.
Join Date: Jan 2013
Location: Seattle Area
Posts: 263
Likes: 0
Received 0 Likes
on
0 Posts
Join Date: Dec 2019
Location: Cariboo country BC
Posts: 14
Likes: 0
Received 0 Likes
on
0 Posts
I have no first hand experience with such, but a little throttle is, I believe, normal procedure when landing on water? Kinda makes sense...
Join Date: Sep 2006
Location: oztraylia
Age: 72
Posts: 32
Likes: 0
Received 0 Likes
on
0 Posts
Really cant get excited until the promoters are excited by the payload and range. You can build an electric anything, the issues are how much useful work can be done, for how long and how long to recharge. Everything else is fluff, window dressing and promotional hype.
I have a cunning plan to extend battery life for aviation, but someone else will surely make money off it, and laugh into the bargain, so I'm keeping this one close to the old chest.
Join Date: Oct 2019
Location: Great White North of the 49th
Posts: 77
Likes: 0
Received 0 Likes
on
0 Posts
I’m in Vancouver for about half the year. Been following this story for a while. Unfortunately I don’t share the same enthusiasm for the project as the manufacturers do. Charging time, the need for many, many identical proprietary battery designs and charging stations at numerous airports, the logistics of change a 1 ton battery between flights and a whole host of other issues makes this a huge undertaking. Battery technology is still not there. Tesla has taken the technology about as far as you can and they are years and years away from any new implementation. While I would love to see it happen, the engine is probably the best thing that comes from this but, until they improve battery tech it’s going to be some time before any commercial service begins, if at all.
Join Date: Aug 2008
Location: Euroland
Posts: 9
Likes: 0
Received 0 Likes
on
0 Posts
Not sure I'd be so pessimistic about this. With legs < 30min this would actually make sense - *if* there is any payload left.
However, as is often sadly the case, they manage to make the maximum buzz with minimum hard info. A lot of speculation floats around. Does anyone know any actual numbers except for the motor specifications (weight / power are known)?
In particular:
* what capacity battery?
* how many kW charging?
* what mass for the battery is actually true? 1000kg has been floated, but no source given as far as I can see. However 1000kg would mean MTOW minus empty weight = zero for the DHC2, even when taking into account that the electric engine is lighter than the combustion one by at least 350 pounds. So that can't be the full story... Did they increase MTOW for this? Otherwise for more than ~1000 lbs battery weight 6 persons on board should be be impossible.
* Battery swapping? This has been floated around, too, but would seem really weird for a floatplane... It also seems kind of useless, since for a leg of 20mins with 30min reserve from the last landing still left in the battery out of the 60 mins total endurance, you'd only have to charge from 50% to ~85%. This can be done with relatively high speed charging, so to get below 15 minutes for those 35% should not be a problem. Probably more than current minimum dock turnaround times, but not that much more to warrant a complicated swap operation...
Anyways, doing this with a 1947 design Beaver of all airframes, is so weird and wonderful that ol'Havilland in his grave probably has a big fat smile on his face...
However, as is often sadly the case, they manage to make the maximum buzz with minimum hard info. A lot of speculation floats around. Does anyone know any actual numbers except for the motor specifications (weight / power are known)?
In particular:
* what capacity battery?
* how many kW charging?
* what mass for the battery is actually true? 1000kg has been floated, but no source given as far as I can see. However 1000kg would mean MTOW minus empty weight = zero for the DHC2, even when taking into account that the electric engine is lighter than the combustion one by at least 350 pounds. So that can't be the full story... Did they increase MTOW for this? Otherwise for more than ~1000 lbs battery weight 6 persons on board should be be impossible.
* Battery swapping? This has been floated around, too, but would seem really weird for a floatplane... It also seems kind of useless, since for a leg of 20mins with 30min reserve from the last landing still left in the battery out of the 60 mins total endurance, you'd only have to charge from 50% to ~85%. This can be done with relatively high speed charging, so to get below 15 minutes for those 35% should not be a problem. Probably more than current minimum dock turnaround times, but not that much more to warrant a complicated swap operation...
Anyways, doing this with a 1947 design Beaver of all airframes, is so weird and wonderful that ol'Havilland in his grave probably has a big fat smile on his face...
Moderator
How easy is it to glide and waterland the Beaver in case of (the electric-) engine failure ?
Does that work out well , without not too many difficulties ?
Does that work out well , without not too many difficulties ?
When I specified the motor arrangement for an electric 172 project, I specified an electric variable pitch, feathering propeller. In the case of power loss, it could autofeather, and gliding would be more easy that many piston powered airplanes.
Yes, as we found, there are penalizing performance (range) considerations for electric planes. But that's going to improve. Every great product improves with development. Ten years ago, you desk top computer might run for twenty minutes on the ten pound back up power supply. Now, a tablet will run all day, doing more work, and the whole thing is 5/16" thick, and weighs a small fraction of the back up battery unit. A battery the size of two choclate bars will start my car! We can't imagine the developments in such a needed product!