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-   -   Electric Rex (https://www.pprune.org/australia-new-zealand-pacific/648023-electric-rex.html)

Stationair8 27th Jul 2022 08:20

Electric Rex
 
ABC news reporting that Rex, plan to retrofit existing fleet with electric-propulsion engines in regional trials.

Looks like a sharp idea.

Mach E Avelli 27th Jul 2022 08:24

Great idea. Leave passengers to fossil fuel fools. There is a growing market in battery transport. Though the return sector could be a challenge.

Capn Bloggs 27th Jul 2022 08:55

Wake up ABC. This, 6 days ago:

https://australianaviation.com.au/20...gines-by-2026/

Icarus2001 27th Jul 2022 12:34

Indeed Bloggs, the ABC article described replacement of the jet engines on the Saab aircraft.

Capn Bloggs 27th Jul 2022 13:36

Iccy, dems propjets!

Guptar 27th Jul 2022 20:59

Interesting analasys on electric aircraft. keypoint, with existing tech they won't work.

https://leehamnews.com/2021/07/01/th...tric-aircraft/

https://leehamnews.com/2021/07/08/th...rcraft-part-2/

Feetweet 28th Jul 2022 00:40

You would also need two totally independent battery systems, not just a single battery. A single battery could possibly lead to a double engine failure given a battery system failure.

Australopithecus 28th Jul 2022 03:34

Currently there isn’t anything with the energy density of fossil fuels, especially jet fuel. Soooo…absent a revolutionary chemistry breakthrough its not going to happen. If it ever does the Saabs will be by then turned into beer cans. Did somebody say beer?

smogluver 28th Jul 2022 04:44

Can’t wait for the first lightening strike

Captn Rex Havack 28th Jul 2022 05:24

Let's just say, in 8 years or so, this actually works. How far ahead of the game will Rex be. Sounds like it's not going to cost them much
so its worth a shot. The rewards could be enormous. Not saying it WILL work, - for a start I'd hate to be trying to get this through CASA,
but if it does, other operators will be clawing to get it.

neville_nobody 28th Jul 2022 05:39

It's never going to happen. Even if they have a miracle and get this to work somehow, good luck getting CASA to take responsibility for certification of something so radical. They make certifying conventional aircraft so difficult a new untested propulsion system for RPT will be impossible. They will not want to take the risk. I don't believe it will even get that far anyway Gas Turbines are too reliable and efficient. All just virtue signalling.

Captn Rex Havack 28th Jul 2022 06:01

Gday Nev

CASA aside - I will go so far as to say it WILL happen eventually.

My dad many times told me that at some time in the 40s his dad looked at the moon and said man will go there one day. My father laughed at him.
Even now, when I look into the night sky I ponder how the fark does a guy fly to the moon. The world is electric these days - aircraft powered
by electric motors seems infinitely more possible than flying to the moon, than taking a heart of one dead dude and putting it in another person,
than hitting send on an email and have it pop up on a screen on the other side of the planet instantly, hell, even more likely than a 575 tonne A380
getting airborne. Electric engines powering an aircraft seems like a piece of piss in comparison to many achievements of the human race.


Alfie.floor 28th Jul 2022 06:35

Anyone smell, government grant?

Traffic_Is_Er_Was 28th Jul 2022 09:22


Electric engines powering an aircraft seems like a piece of piss in comparison to many achievements of the human race.
That's not the point. Electric engines already are powering aircraft. What they can't do, and in all likelihood will never do (using battery storage) is do it economically enough to used commercially. The energy density is lousy, your takeoff weight will always equal your landing weight (unless you have a payload you are dispensing in flight) so no efficiencies to be gained as fuel (weight) is consumed, the time to "refuel" is prohibitive, and the batteries have to go somewhere in the airframe additional to where the fuel tanks might have been, taking up space that should be payload.

Is Rex volunteering one of their 737's? At least then they don't have to worry about the payload hit.

43Inches 28th Jul 2022 12:44

Battery and motor tech has progressed massively in the last 10 years, the projections on energy vs weight for electric propulsion is through the roof at the moment. This is why there are now many projects developing electric vehicles from trucks and busses to planes and ships. Its only a matter of time before there is a major breakthrough in energy storage that will significantly affect this area. I think it's fairly smart to get in on it in any way. The big issue is that this tech has the ability to completely change transportation especially air travel, as having a large bus sized quad-copter is probably where this will go, not necessarily fixed wing aircraft, except for long range. Rex is probably smart to retrofit the SAABs for another 20-30 years of service life until that next step arrives, rather than buy into super expensive step change vehicles in the interim.

43Inches 28th Jul 2022 22:01

Got to love that talking about electric technology is some form of leftist argument. Anyway, thinking Hybrids are some form of efficient tech shows no idea of the engineering. The issue you have with a hybrid is that is carries two energy platforms, so they are naturally heavier than either single power platform. More weight and more complexity means more capital cost, maintenance and operational cost. This is why they dropped the idea in trains and ships and went for more direct drive diesels for efficiency or line fed electric. You have to remember Electric propulsion is just the drive, most new hybrids now are pure electric propulsion with its own little combustion engine electric generator and a set of batteries. With battery technology becoming lighter and more energy dense every year we are already at the point where pure electrics are getting close to the traditional range of similar sized petrol vehicles and are almost the same price as the hybrids that are only marginally cheaper to run than the old tech.

Recycling Li batteries is also 100% possible, is it cheap, no. It's the dismantling process that causes the problem mostly as it's time consuming, so most plants just melt it causing other problems. Now that the material costs are going up it is becoming more economic to strip and recover batteries which in turn means reuse of the components for new batteries etc...

As far as Li reserves there's plenty of the stuff, but not enough mining at present. As with oil, as it becomes more viable to mine they will find new reserves and ways to extract it, as it is fairly widespread, just in trace elements everywhere. That being said Li and Ni are not the only forms of battery under development and traditional acid batteries are being refined as well, which can be used for non weight sensitive applications like household and other uses. I mean you can generate electricity from a damn potato so there's a million avenues to research.

Captain Dart 28th Jul 2022 22:41

So Aer Lingus are looking at spud power for airliners then?

Australopithecus 29th Jul 2022 00:14

There are a few promising battery designs that are too heavy for vehicles, but would be ideal for a fixed application. That would free up lots of trace metals for mobile application. There are flow battery designs that do not degrade with charging cycles for example.

However, as we all know, flying takes a lot of energy and minimum mass. Flying fast even more so. The real physical limitations of batteries are at odds with payload, speed and range to be practical. I am reminded of the nuclear powered B-36 idea that thankfully was rewarded with a head slap.

43Inches 29th Jul 2022 00:54

If you didnt have to worry about containment then nuclear is awesome. Problem is people and radiation etc, etc. The debate and technology with regard to nuclear and space is a different matter with protecting the crew and payload the only consideration, not whether a crash will irradiate a town or city.

Capn Bloggs 29th Jul 2022 01:46

43 inches, you're holding on too tight, you lefty! :O


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