Really interesting new electric plane

[MIFlyer]

Looks like these are planned to be out by 2022 and they plan to use our "underused" airports. I think it's a healthy thing to bring a ton of value to all of our primarily GA airports by making quick 12 passenger flights directly and avoiding the big TSA drama and the major airport hubs.

https://www.reuters.com/article/us-...ter-plane-to-hit-market-in-2022-idUSKBN1CA16A

it does hit against some of the value of GA to us, but it makes this awesome, large network of small airports very commercially valuable and should improve on field services.

 

[edo2000]

That is very interesting, but it is hard to know how optimistic their performance projections are. Also, the article said that these aircraft would be ideal for trips less than 1000 miles, but at the end they mentioned the electric-only range was 100 miles...

 

[Anymouse]

Wasn't there a company that tried this exact same thing with Eclipse jets?

 

[deonb]

That is very interesting, but it is hard to know how optimistic their performance projections are. Also, the article said that these aircraft would be ideal for trips less than 1000 miles, but at the end they mentioned the electric-only range was 100 miles...

"Zunum plans to make a larger plane seating up to 50 passengers at the end of the next decade, and the range of both would increase to about 1,000 miles as battery technology improves, Knapp said."

This is the ultimate in optimism. Trending out the most optimistic trend on battery improvements, we're at 8% improvement per year. (And this has started to slow down).

To get a 10-fold improvement from 100 miles to 1000 miles will require 30 years to get there.

Of course miracle discoveries can happen and advance this, but you can't build a business on betting someone makes a miracle discovery. It's just as likely someone discover teleportation in that time.

 

[Salty]

Flying cars and electric planes. Might as well invest in teleportation devices or unicorn breeding ranches.

 

[steingar]

"And if my mother had wheels she'd be a wagon"

 

[MIFlyer]

Well, I thought the 12 passengers for 100 or so miles to small airports was the game changer. Imagine if there were thousands of these flights a day, taking people not to the big hub, but to their municipal airport a few miles from their home or office. This would lead to lots of improvements for those of us that travel ga. Many more airports would get rental cars and uber. (Maybe even something like zip car). Communities would see more value in their airports because the average citizen would actually use them.

Lastly, I didn't discount as pie in the sky because Boeing and jet blue apparently own this company...


Sent from my iPad using Tapatalk

 

[Salty]

Well, I thought the 12 passengers for 100 or so miles to small airports was the game changer. Imagine if there were thousands of these flights a day, taking people not to the big hub, but to their municipal airport a few miles from their home or office. This would lead to lots of improvements for those of us that travel ga. Many more airports would get rental cars and uber. (Maybe even something like zip car). Communities would see more value in their airports because the average citizen would actually use them.

Lastly, I didn't discount as pie in the sky because Boeing and jet blue apparently own this company...


Sent from my iPad using Tapatalk

My theory is that it's cheap publicity. People get excited and talk. You're talking about Boeing and jet blue, and they didn't have to spend a million dollars on an NFL ad. My other theory is that a fool and his money are soon parted...the guys selling this idea will never produce, but they will make a career out of it.

 

[Todd82]

At best this is nothing more than an EAS bird replacement. Lots of Caravans/PC12s/C402s/PA31s already haul 9 pax and can't make money without a subsidy how will this with 12? CapEx of brand new planes vs 40 year old Navajos you can pick up for $250k? Although if they get to scam free charges everywhere like the electric car people are doing...

 

[Salty]

At best this is nothing more than an EAS bird replacement. Lots of Caravans/PC12s/C402s/PA31s already haul 9 pax and can't make money without a subsidy how will this with 12? CapEx of brand new planes vs 40 year old Navajos you can pick up for $250k? Although if they get to scam free charges everywhere like the electric car people are doing...

That's also a possibility, but considering how difficult it's been to even get a crippled electric plane "working" to pretend the idea is sound, I kinda doubt they'll even make it that far.

 

[edo2000]

Well, I thought the 12 passengers for 100 or so miles to small airports was the game changer. Imagine if there were thousands of these flights a day, taking people not to the big hub, but to their municipal airport a few miles from their home or office. This would lead to lots of improvements for those of us that travel ga. Many more airports would get rental cars and uber. (Maybe even something like zip car). Communities would see more value in their airports because the average citizen would actually use them.

Lastly, I didn't discount as pie in the sky because Boeing and jet blue apparently own this company...

I thought the article was interesting and I appreciate you pointing it out. I agree the concept has a bit more credibility with the investment by Boeing and JetBlue. But, it still does seem like the vaporware which is so common in the aviation industry.

 

[tspear]

A few points to consider.
One. This is a hybrid. It does not depend on some new battery technology.
Two. This plane will fly lower and slower. The means less energy required.
Three. They are planing based on the PR to use an existing airframe manufacturing company.
Four. They are starting with working on the power systems.

Overall, this really is a modest proposal. I can see why Boeing and JetBlue back it. Does not depend on radical or new technology in many areas. Uses known APU for power generation. The goal seems to be to figure out how to best leverage fan propulsion, using minimal battery.
I am willing to bet they did some calculations on battery weight and distance to fit in existing markets.

Tim

Sent from my LG-TP260 using Tapatalk

 

[Salty]

A few points to consider.
One. This is a hybrid. It does not depend on some new battery technology.
Two. This plane will fly lower and slower. The means less energy required.
Three. They are planing based on the PR to use an existing airframe manufacturing company.
Four. They are starting with working on the power systems.

Overall, this really is a modest proposal. I can see why Boeing and JetBlue back it. Does not depend on radical or new technology in many areas. Uses known APU for power generation. The goal seems to be to figure out how to best leverage fan propulsion, using minimal battery.
I am willing to bet they did some calculations on battery weight and distance to fit in existing markets.

Tim

Sent from my LG-TP260 using Tapatalk

Let me just say I will be very surprised if anyone ever makes carrying two motors and batteries that weigh as much empty as they do full into a more efficient airplane. It's not like hybrid cars, which really only work well when they brake a lot. Airplanes don't brake except perhaps for about .01% of a flight; descents don't count unless you are putting out spoilers or air brakes.

The only way the math works is an Elon Musk model of convincing politicians to subsidize it all. Come to think of it, that approach is not new to airlines either....

 

[tspear]

Let me just say I will be very surprised if anyone ever makes carrying two motors and batteries that weigh as much empty as they do full into a more efficient airplane. It's not like hybrid cars, which really only work well when they brake a lot. Airplanes don't brake except perhaps for about .01% of a flight; descents don't count unless you are putting out spoilers or air brakes.

The only way the math works is an Elon Musk model of convincing politicians to subsidize it all. Come to think of it, that approach is not new to airlines either....

Actually the math works do to the cost of energy and MX cycles.
On a per kwH basis, electric is significantly cheaper from a power plant then using Jet-A or avgas. The reason we use Jet-A and avgas is not because of efficiency but because of energy storage requirements.
Then do the calculations for number of cycles and cycle time on a lot of the jet engines. That drives a lot of the maintenance costs.
A brush-less electric motor has effectively no cycle limits. Battery swaps are cheap from a labor perspective.
So if your flight is less than 20 minutes, the generator may never even turn on (and I have been on lots of these flights). Or the generator only runs for a short period....

With a total range of 700 miles, at 340 KTAS that is less than two hours. This is a plane with short legs focused on the feeder airports, or potential feeder airports. If flying less then 100 miles, likely closer to 75, you never turn on the generator. Talk about reduced MX! And the fuel costs, pennies in comparison. I have been on a fair number of Saab 340 flights that last twenty minutes to get to a feeder airport about 75 miles away. This would significantly reduce the costs for the airlines. Potentially making those tickets cheaper... On both coasts, we have all sorts of short flights that are perfect for this type of plane. It really needs a range of 200 miles on the batteries, but 100 is likely the doable number within a decade.

Tim

 

[Salty]

Actually the math works do to the cost of energy and MX cycles.
On a per kwH basis, electric is significantly cheaper from a power plant then using Jet-A or avgas. The reason we use Jet-A and avgas is not because of efficiency but because of energy storage requirements.
Then do the calculations for number of cycles and cycle time on a lot of the jet engines. That drives a lot of the maintenance costs.
A brush-less electric motor has effectively no cycle limits. Battery swaps are cheap from a labor perspective.
So if your flight is less than 20 minutes, the generator may never even turn on (and I have been on lots of these flights). Or the generator only runs for a short period....

With a total range of 700 miles, at 340 KTAS that is less than two hours. This is a plane with short legs focused on the feeder airports, or potential feeder airports. If flying less then 100 miles, likely closer to 75, you never turn on the generator. Talk about reduced MX! And the fuel costs, pennies in comparison. I have been on a fair number of Saab 340 flights that last twenty minutes to get to a feeder airport about 75 miles away. This would significantly reduce the costs for the airlines. Potentially making those tickets cheaper... On both coasts, we have all sorts of short flights that are perfect for this type of plane. It really needs a range of 200 miles on the batteries, but 100 is likely the doable number within a decade.

Tim

That's even better. Let's take a generator and a bunch of gas and don't use it, as WELL as batteries that don't get lighter as they empty. So landing weight is the same as takeoff weight. Oh, and nobody needs a flight to turn around quickly, that's for losers, we can have the planes sitting there idle for 6 hours for a recharge. What a splendid idea.

 

[tspear]

That's even better. Let's take a generator and a bunch of gas and don't use it, as WELL as batteries that don't get lighter as they empty. So landing weight is the same as takeoff weight. Oh, and nobody needs a flight to turn around quickly, that's for losers, we can have the planes sitting there idle for 6 hours for a recharge. What a splendid idea.

I see where you get your username from.

Tim

 

[deonb]

nobody needs a flight to turn around quickly, that's for losers, we can have the planes sitting there idle for 6 hours for a recharge. What a splendid idea.

You can swap batteries. This one is the least of the technological hurdles.

 

[GlennAB1]

A better idea (instead of batteries) might be a small fuel efficient engine driving a gearbox with generators powering those electric motors. Of course, nothing's free and everything has tradeoffs.

 

[Salty]

I see where you get your username from.

Tim

Nah. That would be "grumpy"

 

[Salty]

You can swap batteries. This one is the least of the technological hurdles.

So then you have to buy 3 times more batteries. I mean, the taxpayers have to buy 3 times more batteries. There's no getting around these physical facts.

 

[Salty]

A better idea (instead of batteries) might be a small fuel efficient engine driving a gearbox with generators powering those electric motors. Of course, nothing's free and everything has tradeoffs.

After you get that working, you can replace the small fuel engine with a windmill.

 

[deonb]

So then you have to buy 3 times more batteries. I mean, the taxpayers have to buy 3 times more batteries. There's no getting around these physical facts.

Batteries have a relatively short lifetime. If you use 3 times more batteries, they last 3 times longer.

 

[Salty]

Batteries have a relatively short lifetime. If you use 3 times more batteries, they last 3 times longer.

Since you brought it up, shall we talk about the cost of replacing these battery packs that won't last long with lots of cycles? It makes a tank reseal look cheap.

 

[GlennAB1]

After you get that working, you can replace the small fuel engine with a windmill.

That's just for cloudy day, and takeoff, once we get above the clouds it's all solar.

 

[deonb]

Since you brought it up, shall we talk about the cost of replacing these battery packs that won't last long with lots of cycles? It makes a tank reseal look cheap.

Fun math. Current lithium cell cost is around $145/kWh. If you add Tesla-style thermal management to it, it's about $190/kWh to get a properly contained cooled/heated battery. And Lithium batteries lasts about 1500 cycles with thermal management.

So $190 for 1500kWh over the life of the battery. Add to that actually paying for 1500kWh of electricity at 10c/kWh and you have another $150 - so $340/1500kWh.

1500kWh is about the equivalent power of 40 gallons of diesel raw power, or 44 gallons of gasoline. Taking efficiency of conversion into account (90% for electrical vs. 45% for diesel vs. 35% for gasoline), it's the equivalent of 80 gallons of diesel or 113 gallons of gas burned in combustion engines. If you burn Jet A in a turbine instead (at 59% efficiency), it's the equivalent of 60 gallons of Jet A.

80 gallons diesel equivalent at $340 = $4.25 per gallon.
113 gallons gasoline equivalent at $340 = $3.00 per gallon
60 gallon Jet-A turbine equivalent at $340 = $5.60 per gallon.

Which is why it's disingenuous to just look at the cost of electricity when comparing operational costs - you need to look at the cost of battery replacement as well. It's not fabulous right now (you do have reduced MX though).

However, cost of Lithium cell manufacturing will come down by at least 50% over the next 5 years due to EV manufacturers expecting to make 10-fold increases in manufacturing and building out battery plants, which will bring the $340 down to around $268. And then those prices goes to $3.35 diesel / $2.37 gas / $4.46 Jet-A Turbine respectively, which is competitive.

If only it was actually usable...

 

[tspear]

A few articles backing up your numbers.
Historical trend:
https://electrek.co/2017/01/30/electric-vehicle-battery-cost-dropped-80-6-years-227kwh-tesla-190kwh/

and the effect of the Giga Factory:
https://electrek.co/2017/02/18/tesla-battery-cost-gigafactory-model-3/

Basically Tesla is already down below $124/kWh.

Tim

 

[deonb]

A few articles backing up your numbers.

Thanks, the first one is the $190.

The second one I'm not sure about yet - the entire article is based on this snippet taken from a Tesla store:


I don't know if 35% means cell cost, or battery pack cost. If it's battery pack cost it would be $124. I don't think it is though - the gigafactory won't do much for the cost of a coolant pump. I think it's only on cell cost. If it's 35% on cell cost it works out to be around $140 on the battery. But I'm not willing to use that number either yet because the above isn't much of a statement. But yes, the real number is somewhere below $190.

I always use conservative numbers on this forum otherwise I get clobbered .

 

[Tantalum]

My theory is that it's cheap publicity. People get excited and talk. You're talking about Boeing and jet blue, and they didn't have to spend a million dollars on an NFL ad. My other theory is that a fool and his money are soon parted...the guys selling this idea will never produce, but they will make a career out of it.

Agree

Hybrid airplanes as a concept don't make sense to me, simply because the energy density of the batteries are nowhere near that of traditional fuel. The car is one thing where you spend a lot of time not moving or slowing down and can make use of some regenerative braking Etc. But an airplane that spends the majority of its life producing 65 to 75% of its power I don't see how a hybrid technology adds any efficiency, other than adding costs, complexity, and weight

I believe this is more a way to get people excited, get them talking about their product and brand, and help fund some money for research that will one day be helpful and useful

By the way, I can't picture the general flying public as enjoying spending much more than a few minutes in the 12 passenger plane. Most people generally dislike flying and have anxiety about it, when people tell you that a Regional Jet is slow, cramped, and dangerous, then I don't understand how a 12-person plane is going to appeal to them.

If you want small planes I don't know why the flying wing, or blended wing body concept is dead. You could make a small 20 passenger plane have but be nice and open on the inside with some cleverly placed windows for natural lighting Etc,. Heck, most people these days just close the shades and take out their iPad

 

[Tantalum]

A better idea (instead of batteries) might be a small fuel efficient engine driving a gearbox with generators powering those electric motors.

But then why not just have the small fuel-efficient engine directly drive the propellers, why make intermediary steps between generators and batteries. This is the part I don't understand with hybrid technology. Any time you transfer energy from one form to another you will have some losses, that's just a law of physics, there is no perfect transfer of energy without some loss to heat Etc. A jet engine is remarkably efficient for this reason

After you get that working, you can replace the small fuel engine with a windmill.

It sounds ridiculous but it's a very good analogy actually

 

[GlennAB1]

A single engine propeller up front vs two ducted electric fans in back... propellers have losses on their own. Everything has tradeoffs. Why does one manufacturer use hydraulic actuators and another manufactured use a jackscrew for the same function?

 

[edo2000]

But then why not just have the small fuel-efficient engine directly drive the propellers, why make intermediary steps between generators and batteries. This is the part I don't understand with hybrid technology. Any time you transfer energy from one form to another you will have some losses, that's just a law of physics, there is no perfect transfer of energy without some loss to heat Etc. A jet engine is remarkably efficient for this reason

I agree, in the aircraft example given. If you can't use battery power for the majority of the aircraft's missions, then why carry the batteries?

Where hybrid power systems shine is in reclaiming wasted energy(deceleration) and providing short bursts of power in addition to that provided by the combustion engine(if installed). In cars, they work great in stop and go traffic and are used in many high performance and race applications also. In airplanes, in the future, I suppose they will be used to increase takeoff and climb performance and as energy reclaiming speed brakes on descent. Adds weight and complexity though.

 

[Tantalum]

Where hybrid power systems shine is in reclaiming wasted energy(deceleration) and providing short bursts of power in addition to that provided by the combustion engine(if installed). In cars, they work great in stop and go traffic and are used in many high performance and race applications also.

Exactly!

I only see a hybrid system being useful in a plane is in the example you mentioned, where perhaps it can get you to cruise faster, where the fuel burn is more efficient. But the added weight, complexity, etc. will have a tradeoff.. I am skeptical that there is a theoretical point where hybrids make sense for planes. We may be physically limited at the atomic level of how much energy density can be packed into battery systems. Mind you, despite incremental advanced being made each year in batters we're still well below that of traditional fossil fuels.. it might be impossible to squeeze an equivalent (or greater) amount of energy out of a battery. The math just doesn't add up (yet)

If the environment is the real concern here I imagine some resources may be better spent reclaiming carbon from the atmosphere (I believe there are a few facilities that actually do this) and exploring ways to develop fossil fuels in a synthetic manner. Hydrogen is a great concept too, but that poses its own challenges as well. As it is right now the money and social pressure is on electricity and hybrid cars so that's where the attention is.. ultimately I wonder about the total environmental impact of all of this battery production and lithium mining. I don't believe lithium to be a "sustainable" or renewable resource (but I could be wrong)

Incidentally, I thought this was funny, from one of my favorite web comics, XKCD

 

[deonb]

I don't believe lithium to be a "sustainable" or renewable resource (but I could be wrong)

It is. Lithium can be 100% recycled, but it's currently cheaper to mine it. It's relatively abundant and you don't use a lot of it in a battery (about 2% by mass).

Currently Cobalt is more of an issue - it's hard to mine and hard to recycle. But Cobolt is optional - you can use Manganese instead.

 

[tspear]

I agree, in the aircraft example given. If you can't use battery power for the majority of the aircraft's missions, then why carry the batteries?

Where hybrid power systems shine is in reclaiming wasted energy(deceleration) and providing short bursts of power in addition to that provided by the combustion engine(if installed). In cars, they work great in stop and go traffic and are used in many high performance and race applications also. In airplanes, in the future, I suppose they will be used to increase takeoff and climb performance and as energy reclaiming speed brakes on descent. Adds weight and complexity though.

A few examples where hybrid wins out.

• Think of the plane as designed for a standard flight of 100 miles or less; this is the range of many potential feeder airports to the major airports. e.g. Hagerstown MD to BWI or IAD. White Plains NY to JFK or LGA. If everything goes smoothly the generator barely runs if at all; that is a huge cost savings.
  
• To make a commercial airliner use only batteries is at this stage likely beyond current technology (at least from a practical standpoint). The generator or range extender is a great compromise. It allows the plane to cover many short haul flights with out burning Jet-A and the associated maintenance. It has the generator to extend the range some, so it is not just a one trick pony.
  
• Two turbine engines take almost twice the labor to maintain as a single turbine.
• Two smaller turbines are generally less efficient than one larger turbine.
• Due to possible engine failures, the FAA will not in the foreseeable future certify a single engine FAR 125 aircraft without some backup.
• If you can avoid the fuel and engine cycle; even if just once or twice a day. It can significantly reduce the plane costs.
• Manufacturing costs: two engines are generally more expensive then one larger engine.
  
• Majority of turbofan engines today are designed for high altitude flight. Much cheaper to modify a single larger turbine from a helicopter application which is turned more for lower altitudes.

I am sure there are more. But that is off the top of my head some of the sales justifications; which likely pencil out in favor of such a design.

Tim

 

[Salty]

A few examples where hybrid wins out.

Only if you ignore physics.

Think of the plane as designed for a standard flight of 100 miles or less; this is the range of many potential feeder airports to the major airports. e.g. Hagerstown MD to BWI or IAD. White Plains NY to JFK or LGA. If everything goes smoothly the generator barely runs if at all; that is a huge cost savings.

No. Hauling around a generator, extra motor, and fuel and not using it is not a cost savings.

To make a commercial airliner use only batteries is at this stage likely beyond current technology (at least from a practical standpoint). The generator or range extender is a great compromise. It allows the plane to cover many short haul flights with out burning Jet-A and the associated maintenance. It has the generator to extend the range some, so it is not just a one trick pony.

Hauling around extra equipment does not save money. Airplanes do not benefit from regenerative braking, so there is no advantage to a hybrid.

Two turbine engines take almost twice the labor to maintain as a single turbine.

Don't forget about the electric motor, generator, and batteries you now have to maintain.

Two smaller turbines are generally less efficient than one larger turbine.

Turning fuel into electricity and storing it in a battery, then using it to run a motor is even less efficient

Due to possible engine failures, the FAA will not in the foreseeable future certify a single engine FAR 125 aircraft without some backup.

Not relevant in comparing fossil vs hybrid

If you can avoid the fuel and engine cycle; even if just once or twice a day. It can significantly reduce the plane costs.

Ask a cargo hauler if he'd like to use up his useful load and space on every flight with redundant systems that aren't used.

Manufacturing costs: two engines are generally more expensive then one larger engine.

Again, ignoring the costs of batteries, electric motor, and generator.

Majority of turbofan engines today are designed for high altitude flight. Much cheaper to modify a single larger turbine from a helicopter application which is turned more for lower altitudes.

Not relevant in fossil vs hybrid comparison

 

[tspear]

@Salty
On this one, we are just going to disagree.
I have been following two companies which are building hybrid engines for aviation.
Here is a third company using the same basics for drones: http://www.tflighttech.com/

Tim

 

[Salty]

@Salty
On this one, we are just going to disagree.
I have been following two companies which are building hybrid engines for aviation.
Here is a third company using the same basics for drones: http://www.tflighttech.com/

Tim

Oh, plenty of people will make lots of money from this. Unfortunately it will be collected via the IRS rather than proceeds from it actually being profitable.

I'd be curious to see you explain how carrying around extra equipment that you don't use is saving energy.

 

[tspear]

Oh, plenty of people will make lots of money from this. Unfortunately it will be collected via the IRS rather than proceeds from it actually being profitable.

I'd be curious to see you explain how carrying around extra equipment that you don't use is saving energy.

I do not have the math/numbers to make the case either way. But it boils down to a belief in the following factors:
1. Less cycle time because on some flights the generator will not even be used.
2. Less start/stop cycles because the generator does not need to shutdown and restart to load/unload passengers.
3. Fewer cycles mean fewer maintenance events, which lowers cost.

Turning engines on/off drives the MX cycle on the short haul flights. If this reduction is enough, not sure. You would need to ask an accountant.
Also, I would expect this plane to be cheaper than a twin turboprop. Think about the manufacturing costs of two high precision engines versus one....

Otherwise, we shall just have to wait and see.

Tim

 

[ateamer]

Well, I thought the 12 passengers for 100 or so miles to small airports was the game changer. Imagine if there were thousands of these flights a day, taking people not to the big hub, but to their municipal airport a few miles from their home or office. This would lead to lots of improvements for those of us that travel ga.

Every one of those airports would also get TSA restrictions. Plus they'll need to add to the terminal (or build one from the ground up) for security screening, gates, baggage handling, ticket counters, parking, etc. It will not be a good thing for local airports.

 

[MIFlyer]

Every one of those airports would also get TSA restrictions. Plus they'll need to add to the terminal (or build one from the ground up) for security screening, gates, baggage handling, ticket counters, parking, etc. It will not be a good thing for local airports.

they may get the restrictions just on the terminal that is "secure". I've been to lots of airports that have a big red line around part of the ramp. the rest of the airport is wide open like a normal GA airport, you just can't taxi through the red line. this also made it great for rental cars (available at field) and connections to part 121 service.

agreed, lack of TSA is a huge plus to GA