Apparently, the entire setup is doable for less than $40K. Given the right circumstances (like, an airport at both ends and living in a place with generally nice, warm weather), it could be a fantastic tool for an affordable, fast commute.
> ... it could be a fantastic tool for an affordable, fast commute.
I understand the attraction to owning your own plane and buzzing merrily above the wheel-bound masses below on the daily, but I have to think it's a bad idea (avgas or electric). I think of all the times I've overslept, needed to be at the office unexpectedly, forgot to put some air in the car tires, should get that warning light looked at, etc... phrases that are usually at the start of an NTSB report.
The beauty of airlines and charters is that you're paying them, at least in part, to tell you "no, we're not flying right now." Turns out it can be hard to do for yourself when your job depends on it.
I think the grand idea is that with improvements to battery density and weight this will spill into commercial aviation market.
Small electric planes with lower per-hour operating costs are also a game-changer for flight schools and their students. Cheaper pilot licenses should translate into increased supply of qualified labor and lower the costs of starting/operating an airline.
I am guessing the EV trainer companies have already addressed - but it's not clear to me:
How similar are EV airplanes and ICE powered ones? Aren't there a number of factors that vary from motive power and availability to weight/form factor that make training on an EV not sufficient to training on "the real thing"?
EV airplanes are simpler to fly than a gas powered one, so it could be great for a new student who mostly wants to focus on the actual flying and not so much on how to manage the engine. The current market leader, Pipistrel, is selling an EV airplane that is the same airframe as their gas trainer. So the path for students to transition from the EV plane (local airport circuits and learning landing and takeoff) to cross country (flying long distance, learning judgement about weather, understanding navigation, managing the engine, human factors) is no issue in terms of actual airplane controls and familiarity.
One thing to add is that jet engines are quite different from piston engines with propellers. So, whether you learn in a Cessna 152 and then step up to Airbus/Boeing, or learn in an electric aircraft and then step up, is probably not a dramatic difference.
Note: the article is about an ultralight, which is not really an airplane based on what most people think of: it can only have one seat, cannot be used for commercial activity or flight training. It's for hobby-use only.
> I think the grand idea is that with improvements to battery density and weight this will spill into commercial aviation market.
That's a pipe dream for 2 reasons:
1) battery density is still a small fraction of fuels
2) thus small trainers are about the weight limit you'll see for electric aircraft. There is no path for airliners to propel with batteries.
3) Most of the small electric airplanes have been destroyed in battery fires. So aviation-grade batteries will be needed, and anything certified will be very expensive.
> Small electric planes with lower per-hour operating costs are also a game-changer for flight schools and their students.
"lower per-hour operating costs" would be nice, but fuel is not the dominant cost for flight training, and is not a game changer. In addition, most of the small electric planes you have read about were destroyed in battery fires, killing the pilots.
> Cheaper pilot licenses should translate into increased supply of qualified labor and lower the costs of starting/operating an airline.
No, you're not going to see cheaper pilot licenses (unless you personally open some kind of flight school as a charity), and in the US, the 1,500 hour rule means operating an airline will be expensive. Almost all of the US "regionals" have already shutdown due to a shortage of ATP holders.
It gets old reading aviation news on HN because the fanbois can't separate SciFi from reality. Aviation is an expensive, regulated industry, and will only become more that way.
So let me explain what the game changers are ...
For amateur non-IFR practise and commuting, combining a Sport Pilot or Private Pilot license ($10,000+) with an electric LSA (under 1,320 pounds) plane and free tie-down would be a game-changer for non-commercial use.
(There's no affordable airport access in the Bay Area since tie-downs start at $500/month, and hangars at $1,000/month. No municipality will let you "take off and land" on your driveway in any urban area.)
Otherwise, you're looking at ultralights (under 254 pounds), which is not what most people consider a safe way to commute, but you could trailer. There is one all-metal ultralight, the Hummel, that looks like an airplane, so it is possible to build one for ICE. (See below why that doesn't include electric.)
Note that ultralight weights don't include fuel or pax, so it's that weight plus fuel. (LSAs gross weight is 1320 pounds, so that includes fuel and pax.) However, batteries would subtract from the empty weight, making those categories useless!
What I described above is non-experimental US aviation. If you're clever, there are workarounds using experimental aircraft that can help with the weight limits. However, you can't do any commercial activities, and insurance may not be available for carrying passengers.
So instead of the SciFi nonsense, please follow the above to create a reality-based plan, instead of "Gee-whiz, I can't wait for electric airliners!"
Checklists are key, but the pilot must be willing & able to take appropriate action when a checklist item fails or cannot be completed -- i.e., stand down & cancel, instead of "it should be fine...".
That failure to cancel is two of the three items usually needed for a crash (the failure itself and the bad pilot decision).
The saying pilots generally have is "If you have time to spare, go by air"
Ok, going 40mi you have only so much weather than can go wrong, but I've had friends trapped at an airport due to weather, leave their plane and drive/fly commercial home. It's a fun hobby though. :D
I've known people who commute this way. You have to of course have a backup plan or be able to work from home if the weather is poor. You just have a plane and a car. And there are parts of the US where you'll be able to fly 90+% of the time if you're only going a short distance and not too picky on timing.
It's definitely not practical for most but it would be great. And not having much of a precheck would be really nice.
Light aviation in general is an incredibly bad idea from a safety perspective [1]:
> Taking the preliminary 2013 fatality rate in general aviation of 1.05 fatalities for every 100,000 hours of flight time and scaling it up to 2 million hours gives a comparison rate of 21 general aviation fatalities per every 2 million hours. This suggests that stepping on a private plane is about 19 times more dangerous than getting into the family sedan.
There is a combination of increasing energy density of batteries and decreasing cost of high tech motors that I believe is a bellweather for electric flight experimentation, particularly on the LSA/ultralight end of aircraft.
While I believe it is unlikely we will see energy densities on the level of gasoline anytime soon, I do think we will see a lot of innovative electric training aircraft soon. If lithium sulfur batteries live up to the hype then we might see even cooler designs.
Better still with an electric motor you have more options for motor placement. You don't have a big fat engine that has to be placed in the front[1]. The batteries don't have to sit in the wings, they can theoretically sit at the bottom of the plane making weight easier to manage.
You also get more options for blade types. Like ducted fans.
In short, your plane doesn't have to be designed around a fat gasoline engine and tanks. There's still constraints, but you get much more creative freedom.
I expect when we see planes designed around the motor/batteries we'll see aerodynamics get electric planes into GA territory.
EDIT: aerodynamic efficiencies.
[1] Yes there's that tractor/pusher Cessna, no one liked it.
In a lot of ways, you prefer the battery weight to be in the wings. The main one is that it reduces the load on the critical wing-fuselage junction (the source of zero-fuel-weight limitations in larger aircraft).
You can package things however you want, even in weird shapes. Not "has to allow liquid to flow downhill, even in rate 2 turn". I'll bet there's still wins to be found even with putting batteries in wings.
Yes definitely. Most electrical planes currently in the process of certification are hardly using the latest & greatest in terms of battery technology. The reason for this is not that the technology is not there but that resetting the process of certifying the airplane and batteries extends the time to market by years and everybody is scrambling to get certified now so they can start fulfilling orders. Like with EVs, demand is not a problem for any of these manufacturers.
This is true for Bye's eflyers, the Eviation Alice, the Pipistrel models, etc. These have modest but usable ranges (currently advertised) and are far enough in the development process that they might hit the market in some modest numbers in the next few years. But that's with battery technology of basically a few years ago. There's obvious room for improvement by simply updating the battery technology. 2-3x over the next decade is not an unreasonable expectation; the biggest hurdle is certification.
The real thing to look for with electrical planes is range & operational cost. Yes it's annoying to not be able to fly 5 ours straight. But 2 hours is still pretty good. This would require doubling the power/kg for this plane, which sounds like it should be feasible; if not now than maybe in a few years. Also, turning a 100$ hamburger into a 5$ latte flight is going to be quite literally be the difference between being able afford to fly or not at all for a lot of people. GA flight is a really expensive hobby currently.
I think what will happen is the experimental market exploding pretty soon. There's a critical mass of technology coming on the market and it's going to be very tempting for people to start building kit planes they can actually afford to fly. There are some fine examples of some daredevils on youtube flying some DYI contraptions already.
If you weren't so worried about having a reasonably-sized airframe or high speed we're getting pretty close to significantly increased duration/range via solar.
It's got 95sqft of wing and a top speed of 63mph. Drag is usually with velocity squared so going 1/2 as fast might only require 1/4 as much power.
They state in the article that it takes 10kw to fly level. With 100sqft and an average 10W/sqft you're at 1kw. But cut the speed down to 30mph (2500W) and double the wing area (2000W) and you're very nearly at breakeven. The 11kw battery might then last you 10+ hours after accounting for the power required to climb out.
Yes it'll end up being much more of a power glider than a "proper" airplane but that might be a lot of fun.
By training, do you mean for training beginner pilots? I would think there's a lot of benefit from learning on aircraft similar to what you'd pilot post-training.
The fundamentals of flying can be learned in any aircraft. Pilots are already trained on "trainer" type aircraft, because they are more forgiving and more economical to operate than aircraft designed for another task.
Yes, changing types will require some training, but it's a big savings if you can get your PPL in a plane with an operating cost of $1/hour. If you look at vendors that are selling production electric aircraft, they claim 70% savings on training operations. That's a big deal. (Link: https://www.pipistrel-aircraft.com/aircraft/electric-flight/...)
There's not. Airline pilots don't start out in airliners. They don't even start in turbine-powered aircraft. They usually don't even start in multi-engine aircraft. That's because learning how to fly is hard enough without also learning to operate a very complicated machine.
Learning to fly at its most basic is much more than just stick-and-rudder skills. There is a lot of information to learn, procedures, airspace, radio work, etc.
It's best to learn how to fly in the simplest safe aircraft possible. Then when you have to learn to operated a very complicated machine you don't even have to think about the flying part.
Complex aircraft are also much more expensive per flight hour, so it makes sense to learn on the cheapest safe thing you can fly then let your employer foot the bill for the type rating.
Managing the engine is not the most important part of flying, especially for ultralight aircraft. And in fact, the best pilots tend to be also experienced glider pilots.
Also, one specificity of ultralight flying, or at least the way I was taught, is to not trust the engine, no matter how reliable it is supposed to be. One aspect is to make the final approach unpowered. Of course, the engine is still running, but ideally, you should pull the throttle all the way back and leave it here, as if the engine had failed. This is in contrast to the 3° slope commonly taught in general aviation.
Of course, a pilot who only flew on an electric plane needs some time with a flight instructor in order to learn the quirks of gas engines, but that should be quick compared to the time it takes to actually learn how to fly.
Almost every pilot starts their training in a Cessna because the basics of flight apply to every aircraft, and operating a small simple aircraft is far less cognitive load than sitting in the glass cockpit of a jumbo jet. An electric plane removes the complexity of operating the engine which is not insubstantial, even in the smallest of general aviation aircraft.
I kind of hate Cessnas. They feel dramatically underpowered to me. Sailplanes OTOH feel great because they have no engine at all. It--focuses the mind. I've probably learned a lot more about pure flying from sailplanes than from Cessnas. It just feels safer to me to have no engine and a good glide ratio than a small (potentially unreliable) engine and a poor glide ratio.
Of course nobody's going to be commuting in a sailplane, but they're awesome for pure fun and learning piloting skills.
They also don't get lighter as they lose energy, which is key to large passenger jet operations. Large plants often take off heavier than the plane is rated to land normally expecting to burn that weight in flight.
Batteries have a much lower specific energy that hydrocarbon fuels to start with, and then that fact that the aircraft weight does not decrease over the duration of the flight is one more disadvantage (currently a second-order issue, given the first difference.)
These are constraints that can be designed around, and you have more freedom to do so when designing from scratch, but doing so is not a optimization, it is a straightforward trade-off between weight and duration. There's no optimal hump on that line.
The fact that H2 can't be stored as liquid, even under pressure makes me pretty doubtful. I suspect ethanol or plant-derived oil will beat out hydrogen for as long as batteries aren't up to the task.
You got me thinking, so I looked for some numbers.
Hydrogen has a specific energy of 120 MJ/kg, while Kerosine has 46 MJ/kg. According to the abstract of the paper being discussed here, the new material has a deliverable capacity of 14% by weight, corresponding to about 17 MJ/kg - only a bit better than 1/3 that of kerosine, but considerably better than lithium ion batteries, which apparently achieve less than 1 MJ/kg, while the best-performing lithium-sulfur batteries are at about 1.8 MJ/kg.
In addition, we must deal with this material only losing 14% of its weight as its hydrogen is used up, while kerosine loses all of its weight - a combustion-powered airplane becomes more efficient as its fuel is consumed.
Furthermore, to get that 14% deliverable capacity, you have to start with it at 100 bar, so the tank containing it will have a substantial weight.
So we have progress here, but not yet a substitute for liquid hydrocarbons.
Yeah, I think that's more likely. But for all electric I think hydrogen makes more sense than batteries, since improving batteries enough for real applications requires new chemistries, while I think the obstacles for hydrogen are more about economics.
No, look at the prices and requirements for a hydrogen storage tank, you either need a high pressure tank or one that can handle very low temperatures. Neither is cheap or simple.
Lithium sulfur still has a tiny fraction the energy density of hydrogen. It's very unlikely, probably impossible, to ever beat hydrogen on energy density with a battery.
Also, Li-S still has too low of energy density for airplanes, and given the long recharge time problem batteries fundamentally are a no-go in aviation.
LiS is only 10x below gasoline. When you account for the difference in efficiency, and the the difference in weight for the motors, and then reliability and redundancy, it is roughly a factor of 2 away. That is fine for shorter routes.
Recharging time isn't an issue, just have the batteries swappable.
One of the biggest reasons I gave up flying is due to the extremely expensive nature of the hobby. Something like this with its sub $2/ hour cost would be very appealing to me. Also since it's an ultralight with a steep rate of climb, I might be able to take-off and land on my driveway.
I'm particularly curious about how this would work with a hybrid glider or other aircraft with long glide paths where you could use the electric to get up to elevation and glide the rest of the flight.
I spend more than $2/hr on my prop maintenance and over $1/hr on tires (and that’s for several hours average per flight). I’m skeptical that electric propulsion will revolutionize basic aviation training or reduce the costs to make it a commonplace activity as it appears to have been in the heyday of the 60s and 70s, which was well before my time.
Yes, I'm greatly overstating the costs involved. But reducing the fuel cost from $35/ hour for a Cessna burning 10 gallons/ hour to burning $3-5/ hour worth of electricity would be a pretty big deal.
A C172 rents (including fuel) for $155/hr with steam gauges and $175/hr with a glass panel at my local flight school. Way less than half of that is fuel, and no one's getting rich leasing C172s to flight schools.
I think you might see rentals come from $155/hr to $125/hr. I doubt you'd see them go under $100/hr, and I'm not sure that's enough of a difference to drive a material increase in student traffic or affordability.
Believe me, I wish it would. I started flying almost 25 years ago and it was much nicer when the airports were busy and when trade professionals (plumbers and electricians) could afford to fly. Now, I mostly see doctors and tech people at the airport as new student starts and that's not enough to really sustain vibrant airport businesses.
Last time I rented I was renting a Cessna Wet at about $85/ hour as part of a club. Fuel costs were about half of that.
Engine overhauls every X,XXX hours was another, but I'm not sure if you need an engine overhaul on an electric plane. How does battery replacement stack up against fuel tank replacement/ leaks? This is all up in the air, but based on the difference in ICE car maintenance versus electric, I'm pretty optimistic that there will be more savings than just the actual fuel costs.
But even you ignore other potential savings, just fuel savings alone drops prices by 35% using your numbers which is a pretty big savings.
Operational cost for a cessna also includes maintenance, engine overhauls & inspections (and lets face it repairs), oil changes, etc. This adds up to about almost twice the fuel cost.
That's why people talk about the 100$ hamburger. Because if you add it all up that's what you are spending per hour roughly.
With electric, you fly way cheaper than that because the components are cheaper, more durable, and way fewer in number and there is just a lot less that goes wrong with these planes. That and the fact that electricity is dirt cheap. This ultra light sounds like a pretty cheap thing to fly.
Fuel cost for a Cessna 172 is maybe 50 $/hr (10 gallons per hour times 5$ per gallon), while the plane rental (wet, including fuel) is about 180 $/hr. So, even if you’d get the fuel price to zero, you’d reduce the rental price by at most a third.
The founder (a fighter pilot) originally built a civilian fighter jet with Israel Aerospace Industries years ago. He also built an advanced solar electric UAV which DARPA is using to "ambitiously" try to recharge drones with a laser.
> You have to be careful of people standing around because when the master switch ... is on, the motor ... can silently spring to life at an inadvertent bump of the throttle.
The commercial version of this should probably "idle" the propellers at 30 RPM or something... fast enough to notice, without burning much power.
Is it not possible to add an efficient internal combustion engine, couple to a generator, lower capacity batteries and an electric motor to power these planes?
Battery energy density is very less, but having a constant speed small, optimised IC engine to generate electricity from fuel could increase range and capacity of these planes.
I think we are doing something very wrong with electric airplanes- namely, the idea, that you have to have one craft that has to archieve vtol lift off. My Question: Why?
Why not a tug drone, that gets a plane up to altitude in a VTOL way, fly with full battery capacity and then land with a rotor arrest like a helicopter - with the tug long detached and returned.
The tug could be more like a powerbank. It would not physically pull the aircraft up but assist by providing power. The aircraft could launch on its own but it is advantageous to use a tug because this increases the range or energy reserves that the aircraft itself has.
(outline of a launch: aircraft and tug are connected by cable before launch, both lift-off, gain altitude, cable is detached, aircraft moves on and tug returns to launch site)
Except you probably have another aircraft already landing, the slots are tight.
Maybe you could have another shorter landing strip just for the tug, but again, that seems like a lot of complexity (i.e risk) for maybe a 20% increase in efficiency at best.
That's an interesting and unconventional idea. If I remember Lilium's [0][1] numbers correctly, most of the motor power is needed for vertical take-off and landing and only a small fraction (1/10 to 1/5) is needed when they have transitioned to wing-borne lift. This means that supporting the aircraft for just 1 minute during take-off would give 5-10 minutes of extra vertical flight, which translates to 25km-50km of extra range at a cruising speed of 300km/h.
Apparently, the entire setup is doable for less than $40K. Given the right circumstances (like, an airport at both ends and living in a place with generally nice, warm weather), it could be a fantastic tool for an affordable, fast commute.
Here's another story by Gabriel about completing a 100-mile journey: http://inspire.eaa.org/2020/01/09/99-miles-on-batteries/ (with recharging stops).
It looks like the maximum range of his setup is 60-miles, but with what he considers a "safe" amount of margin, he limits his trips to 40.