PPRuNe Forums

PPRuNe Forums (https://www.pprune.org/)
-   Australia, New Zealand & the Pacific (https://www.pprune.org/australia-new-zealand-pacific-90/)
-   -   Electric Regional Aircraft in Service by 2026? (https://www.pprune.org/australia-new-zealand-pacific/642212-electric-regional-aircraft-service-2026-a.html)

27/09 19th Aug 2021 00:01

Electric Regional Aircraft in Service by 2026?
 
Saw this today.

https://www.stuff.co.nz/travel/green...ric-plane-deal

This is the company who is making the aircraft. https://heartaerospace.com

Frankly I think they are being a tad optimistic with their 2026 operational date. Right at the moment I see it as just attention grabbing headline pie in the sky stuff. It could happen one day but not this decade in my opinion. I wonder what other people think.

Certifying an new airframe and new propulsion technology along with having to develop all electric systems for air con/pressurisation etc will be a challenge.

Ascend Charlie 19th Aug 2021 01:52

Might work in NZ for the hop across the Straits or over their steep hills. The 750m runway length sound a little optimistic for a 19-seater, though?

As 27 September says above, the time line for certification seems pretty brave.

43Inches 19th Aug 2021 02:27


The 750m runway length sound a little optimistic for a 19-seater, though?
Electric engines are light and high torque, and with that arrangement across the wing would all lead to good field performance. One huge advantage to electric is you can have multiple motors for very little weight penalty. Downside, the batteries more than make up for the loss of engine weight, and don't get lighter as you fly either.

KeepItStraight 19th Aug 2021 03:57


Originally Posted by Ascend Charlie (Post 11097636)
Might work in NZ for the hop across the Straits or over their steep hills. The 750m runway length sound a little optimistic for a 19-seater, though?

As 27 September says above, the time line for certification seems pretty brave.

750 metres does indeed seem a little optimistic. Though that's pretty much in line with all the other optimism they show about what it'll be capable of and when it will fly.

Interestingly there's an outfit in the US doing a hydrogen fuel conversion on a couple of Dash 8's. They already have a proven airframe and their projected certification is towards the end of the decade and yet Heart is spruiking 5 years away for a brand new airframe and propulsion system. I really think they have their ambitions and abililty in the wrong order.

43Inches 19th Aug 2021 04:11

I agree it's ambitious, but 750m is achievable for that size of aircraft if the wing and lift devices are right for it. Do 228 is around 800m at MTOW and the Dash-7 which is a similar layout using propwash to aid lift production is under 700m.

Anti Skid On 19th Aug 2021 07:12

The logical solution (and I believe Boeing are working on this) is a hybrid. We all know most energy is used during taxi and climb to cruise. Having an APU to generate electricity to power the motors also means you don't need fully charged batteries (and you have to consider how long they would take to recharge).

At cruise and descent the APU would be off, relying only on batteries

https://www.stuff.co.nz/business/976...market-in-2022

KeepItStraight 19th Aug 2021 09:32


Originally Posted by Anti Skid On (Post 11097731)
The logical solution (and I believe Boeing are working on this) is a hybrid. We all know most energy is used during taxi and climb to cruise. Having an APU to generate electricity to power the motors also means you don't need fully charged batteries (and you have to consider how long they would take to recharge).

At cruise and descent the APU would be off, relying only on batteries

https://www.stuff.co.nz/business/976...market-in-2022

Zunum are no longer. I think their concept had a better chance of success than Heart's EP19. I wonder how long Heart will survive.
https://en.m.wikipedia.org/wiki/Zunum_Aero

43Inches 19th Aug 2021 09:47

Charging rate for batteries is dropping dramatically each passing year, there's talk of 5 minute car chargers in the next few years. Some are already down to 15 minutes. That aircraft they are talking 40 minute full charge.

Battery technology is really advancing at a massive rate, that will be the main driver of everything electric from aircraft to farm vehicles, trucks, cars and ships.

Hybrids just carry too much weight of having the two systems combined, the whole trip you are paying the fuel price of the extra weight of whatever is not being used.

27/09 19th Aug 2021 10:08


Originally Posted by 43Inches (Post 11097827)
Charging rate for batteries is dropping dramatically each passing year, there's talk of 5 minute car chargers in the next few years. Some are already down to 15 minutes. That aircraft they are talking 40 minute full charge.

Battery technology is really advancing at a massive rate, that will be the main driver of everything electric from aircraft to farm vehicles, trucks, cars and ships.

Hybrids just carry too much weight of having the two systems combined, the whole trip you are paying the fuel price of the extra weight of whatever is not being used.

I'm not sure everyone agrees about the use of batteries.

Hydrogen aircraft being developed here https://www.seattletimes.com/busines...-lake-venture/

cattletruck 19th Aug 2021 10:41

Wouldn't it be cheaper and perhaps more sensible to take say a Dash-7 and create a hybrid job out of it with electric engines for number 1 and 4.

But if you did go fully electric, could you redefine fast charging by flying near a Cb looking for a lightning strike. Don't laugh, current fast charging for cars is looking at pumping 600kW into their batteries in just a few minutes which is quite a bomb of energy.

Ho-hum, yet another glossy CGI rendering of the future, yawn.
To paraphrase Yogi Berra, "The future ain't what it used to be."

43Inches 19th Aug 2021 10:44

Hydrogen would be the natural go to for the big companies, you can then control the fuel like oil now. It might be clean burn energy but it still costs a lot of energy to make mass amounts of hydrogen. Pure electric you can charge off the wind, sun, tide, thermal for free once you set it up. Great for the masses but not so great for collecting taxes and supporting infrastructure.

You could make your own hydrogen, but why bother when you can just power your vehicle with the energy directly without complicating the situation.

Anti Skid On 19th Aug 2021 11:31


Originally Posted by cattletruck (Post 11097859)
Wouldn't it be cheaper and perhaps more sensible to take say a Dash-7 and create a hybrid job out of it with electric engines for number 1 and 4.

But if you did go fully electric, could you redefine fast charging by flying near a Cb looking for a lightning strike. Don't laugh, current fast charging for cars is looking at pumping 600kW into their batteries in just a few minutes which is quite a bomb of energy.

Ho-hum, yet another glossy CGI rendering of the future, yawn.
To paraphrase Yogi Berra, "The future ain't what it used to be."

Not quite the same, but the RNZAF P-3 Orions use two engines to increase endurance on patrol

smiling monkey 19th Aug 2021 13:02

I wonder how you'd carry 30 minutes holding in an electric powered aircraft? Carry an extra powerbank in your nav bag? :confused:

morno 19th Aug 2021 15:11


Originally Posted by smiling monkey (Post 11097953)
I wonder how you'd carry 30 minutes holding in an electric powered aircraft? Carry an extra powerbank in your nav bag? :confused:

How do you carry it now? In a Jerry can?

Think hard. Imagine a battery being just like your fuel tank, and the charge on the battery being the fuel that you put in the tank :hmm:

Shackeng 19th Aug 2021 16:18


Originally Posted by Anti Skid On (Post 11097898)
Not quite the same, but the RNZAF P-3 Orions use two engines to increase endurance on patrol

As did Nimrod.

Global Aviator 19th Aug 2021 21:12

The first commercial electric aircraft -

https://www.aopa.org/news-and-media/...lectric-beaver

So yes using old airframes has been proven to work.

43Inches 19th Aug 2021 23:04


The first commercial electric aircraft -

https://www.aopa.org/news-and-media/...lectric-beaver

So yes using old airframes has been proven to work.
It works yes, good to prove a point and get things rolling. A long lasting successful design will need to be optimised for the technology, therefore offering much better efficiency and operating costs. Using the technology to its full extent means you can save a lot of weight and offer better performance over the present machines.

If you look at cars simply retrofitting a petrol design works, but it is increased weight and poor weight distribution. A purpose built car with in hub motors, batteries set low along the chassis and low weight structure that does not have to carry the forces of engine torque and transmission makes fro a much more efficient vehicle. Hence when you weigh up hybrids, the technology is eco consumer appealing but doesn't achieve much in actual cost savings.

Dash-7 is a 40+ seat aircraft, and limited airframes remaining. Not really sure it would make a great test bed, to carry the two outer heavy turbine engines and accessories the wing structure has to be heavier, wasting weight on structure that's not required.

BTW engine efficiency for electric is very different to turbine or petrol. So switching off engines in flight is not really any better than keeping them running at low power/drain, it's probably worse, as the dormant engine will just create drag.

No Idea Either 20th Aug 2021 00:20

Read an article a few years back from RMIT IIRC about Aluminium ion batteries in development. They didn’t hold much MORE charge than a Li ion battery but you could plug them in and fully charge them up in a few minutes……that would be a game changer!!

27/09 20th Aug 2021 01:49


Originally Posted by No Idea Either (Post 11098207)
Read an article a few years back from RMIT IIRC about Aluminium ion batteries in development. They didn’t hold much MORE charge than a Li ion battery but you could plug them in and fully charge them up in a few minutes……that would be a game changer!!

That doesn't solve the issue of energy density which is the other big stumbling block which I'd argue is more of an issue than the charging time.

27/09 20th Aug 2021 01:55


Originally Posted by Global Aviator (Post 11098141)
The first commercial electric aircraft -

https://www.aopa.org/news-and-media/...lectric-beaver

So yes using old airframes has been proven to work.

Everything I've seen so far on the electric aircraft front whether it be small like the Pipstrel, or Beaver/C208 size, is there's about 1 hour of endurance. That's a long long way short of the normally accepted endurance. Sure 1 hour is OK for niche markets but it doesn't cut the mustard for most routes and especially IFR where alternates are required. A long way to go yet. One article I read said up to 20 years before commercial services with electric aircraft became common place.


All times are GMT. The time now is 06:02.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.