Saw this article on the Flying Magazine website about the Bye Aerospace eFlyer 800. An all-electric “turboprop-class” 8 seat aircraft in development in Colorado. The speed and payload numbers look good. The range, not so much. Also wondering where you would charge this.

Looks good though!


https://www.flyingmag.com/resizer/3thOH ... IBVCAU.jpg


https://www.flyingmag.com/story/aircraf ... w-details/

If it had more range, I’d see how this could compete with my Cheyenne. Charging it back up would seem to be quite the challenge though. Could work well in the air taxi, cargo, and regional carrier role as stated in the article. What does the BT crowd think?

Regards,
Rob

Just keep a couple turbine engines on it and it’s what today’s KingAir should look like.

Yes. Put some -52s on it and you’d have a rocket ship.

There's not a lot of reality in the idea.

A parachute? This plane is going to weigh in at 15,000 lbs or more, so that parachute is going to have to be enormous and heavy. With twin electric motors, dual windings, quad batteries, just exactly when are you going to need a chute? Ditch the chute and make the plane lighter or use that weight for more batteries.

500 nm plus 45 min IFR reserve isn't bad. Many destinations fit within that realm. But you often want to go and come back soon after, so it isn't the leg range that is the problem, it is the fact you can't refuel it and come back. It is a one way ticket to wait many hours recharging. And it won't do that from a wall outlet, the airport will need special high power service and charger.

It is going to need a minimum 1000 KWH pack or so by my estimation. A Tesla model S pack is 85 KWH and weighs 544 Kg, or 156 WH/Kg. Let's say they can get to 220 WH/Kg, which is doing very well, 50% better than Tesla can do, then they need a pack of 4500 Kg, or almost 10,000 lbs just for the battery. Does not compute.

Also, don't forget the power to pressurized the cabin and to deice the airframe. Those will kill range.

This is a dream. Won't become reality.

The best electric airplane idea I've seen is this:

https://www.avweb.com/aviation-news/sol ... e-venture/

These are very short range flights, like 20-30 minutes, can be recharged at the dock relatively fast, and they fly over water so much that they almost always have a place to land if the battery poops out. That idea makes some sense and is a good launch project for commercial electric flight.

Mike C.

It's sexy. I don't worry about recharging like Mike, because that's an easy problem to solve.

But 500NM with 45min IFR, that's a lot of batteries!!

You've not run the basic math.

1000 KWH pack to recharge in 2 hours will take 600 KW service to the charger.

This may need a new line on the poles to the airport. Will definitely need a new transformer, one that probably produces 960 volt service.

The charger will cost major money, probably 6 figures, and you can't bring it with you, too heavy.

If you land at an alternate, and all they have is 220 volt 30 amp service, it may take 10 DAYS to recharge the airplane at 5 KW charge rate. The fastest way to deal with it will be to rent an industrial trailer generator, a 500 HP one will get you charged in about 4 hours. So much for not making CO2, however.

Mike C.

I think they said they're looking at the Li-Sulphur technology which has a capacity of up to 500wh/kg. Problem I've heard with those batteries is that they don't have as many cycles in them as Li-Ion and will need replacing. On the other hand, Sulphur is probably the most abundant material on earth, so should provide for cheaper chemistry.

Exciting times ahead. I personally can't wait to get rid of the monkey motion stuff.

When hell freezes over and this enters the commercial market there will be plenty of Sulfur and even some Brimstone!

The recharge time is a big issue. Plus the dead weight of the batteries. Weight reduction as fuel burns off and being able to adjust your fuel load at takeoff are huge advantages for conventional engines.

Probably electric aircraft won't see any large measure of adoption unless there is a way to physically remove the batteries and replace them with fresh ones to save time on "refueling". Removing batts would help the deadweight problem in some situations but might create others (if you don't remove the unneeded batts at your home field you have to transport them back some other way).

Removable batts might be more workable for cars due to the scale involved. Tomorrow's service stations could give you freshly charged batts instead of gas.

The fact is, if airplanes were originally electric, the advent of liquid fuel-powered engines would seem like a great advance and improvement (that scenario historically did actually play out for cars but looks like we're coming full circle now).

What if they used hydrogen-electric? https://www.aviationtoday.com/2021/03/02/hypoint-ceo-talks-new-hydrogen-fuel-cell-operable-prototype-electric-aircraft/

Perhaps have 45-minutes of battery on board as a capacitor/buffer with the rest of the energy coming from a hydrogen-powered generator?

I never do. As I live off batteries for 6 months of the year my math gets squirrely.



Solvable problem though, correct?


Maybe. Have you priced what it cost to put fuel tanks at an airport. How about transporting said fuel to the airport, or the cost to put that fuel in an airplane.

I think a more realistic 'refuel' time is around 5 hours. This airplane may not be suitable for all applications.

CO2 and other earthly problems are going to be unsurmountable here soon.

If this were software it would be called ‘vapor ware’.

I don’t know if swapping CO2 for rare earth metals and Sulphur is a trade an intelligent environmentalist wants to really make.

If I were designing one of these concepts I would study mounting batts on underwing hard-points (like a smart bomb). And yes, I would be able to pickle them off the aircraft. A battery fire would be a major concern of mine.

The solution to quick turn arounds is having hot swappable batteries in wait.

This makes a lot more sense than batteries on this type of aircraft. You'd have better range, fast turn around, and limited exposure to battery related issues of weight and fire.

Everybody thinks Electric = Batteries. It doesn't have to.

Agreed on all points, especially the CO2 piece.