Heart aerospace completes first flight of largest electric aircraft(heartaerospace.com) |
Heart aerospace completes first flight of largest electric aircraft(heartaerospace.com) |
The region they did this flight in charges ~$.25/kw. So they would have had to do the entire flight with 20kw/h or an average of 40kw of output. That’s 60hp, or about a third what your Cesnna uses on climbout. Even if you give them a very low price of $.10/kw then they are flying with less than the Cessna on climbout. Hell, a Cessna in level flight uses ~80 kw.
In other words, they are claiming that they can fly this thing on a VW beetle engine, or the PR guy got the number wrong.
A Dornier 328 (roughly similar in size) has two 1625 kW engines. Heart stated they "delivered more than one megawatt of power" during the flight, so maybe comparable to one of the Dornier's engines at 60% power? Even the DC-3 could take off with one engine but 60% seems iffy.
At 1000 kW and $0.10/kWh (being very generous I think), the plane would be using $100/h (at 1000 kW level) or $1.67/minute. You'd blow past $5 in 3 minutes.
I don't like that they don't share the basic numbers. It's as if they don't want folks doing the math.
I was wondering how they're gonna deal with alternate airports and "fuel" reserves, but it seems they also have generators on board (supposedly used in case of emergency / unplanned detours).
I wonder, if this can get approved or certified somehow now, if then modifications and improvements are relatively easy, as long as many aspects like the pilot interface stays the same. Battery technology improves constantly after all.
As an example, going from the current 200 km range to 400 could make it very useful in numerous regions certainly.
I wonder if there is a possible future where some sort of commercial long haul flights could be done by a fully electric plane. I've never gotten a great answer on this, and maybe we don't have an answer for certain since battery chemistry is some sense is still early days
Perhaps if solid state batteries become cost effective to produce at scale that would change the feasibility, but someone else would have to chime in there.
It's fun to look at the arithmetic behind this to pull out the assumptions. To lift a 25000 lb mass 1100 ft in the air requires just over 10kWh, but that's assuming no air resistance or friction, so let's triple the energy needed to 30 KWh.
Let's add another 10 kWh for forward distance covered (assuming it was mostly gliding). Then let's pad it up to 50kWh for anything else. If they say that was $5 in electricity that implies an electricity price of $0.10/kWh, which is possible with utility scale solar.
I'd guess the actual flight time was only 10 of the 27 minutes, 30 kWh used over 10 minutes is 300kW of peak power.
300kW seems very low compared to equivalent jet powered planes, which output an order of magnitude more power for a 30 seater plane. Even if the electric drivetrain is far more efficient than a jet engine it stretches credulity.
Which of my numbers is off?
I would note this line from the press release:
> its all-electric propulsion system delivered more than one megawatt of power.
I assume this was peak during takeoff.
Finally, I think you might be still high on the power cost. $.10/kwh is retail cost in the PNW, they might be, um, bullshitting a little and have purchased power at a very good rate at a particular time just so they could say $5. They didn't say every flight would be $5. So energy could have been 3x more than you estimated.
I'd love to see something that can do around 250mi. It would be nice to electrify transit in the Texas Triangle if we end up never being able to actually build useful HSR.
I wish them luck on continuing to try!
Conclusion: AI wrote this article and it has at least one and probably several more errors.
Even if the initial cost of an electric plane is higher than a combustion equivalent, the cost of the aircraft itself is only 5% of its lifetime cost. So an electric aircraft's purchase price could be twice as much and still represent a cost savings for an airline. And that's not even counting other advantages such as reduced maintenance needs for EVs.
You better start working on them now if you want them to be ready when they'll make economical sense, which might be in a not so distant future
And for medium haul they make sense if you can get beamed power working.
that could make it much more convenient and appealing as a travel method
Napkin math:
(27 minute flight) * (25000 lbm TOGW) * (Earth gravity) / (~10 average L/D) * (160 KTAS average) / (70% propulsive efficiency) / (97% coulombic efficiency) * ($50/MWh) = $30
(Add residual kinetic energy upon landing too)
Side note: Heart also has a weight issue here they'll need to overcome if they want to certify under FAR Part 23 (as their 19-pax spec implies); TOGW limit for that is 19,000 lbm.
Are you literally paid for agreeing to receive the energy?
Further, noise restrictions will probably limit VTOL's to airports, never underestimate the NIMBY's. Note that demo videos of eVTOL's almost always have background music rather than ambient sound.
They could also use electric tugs to and from the runway, not just at the terminal.
But, as a general thing? I don't see it happening. There's a TON of complexity in a catapult system.
Plus, the amount of spilled champagne in first class is going to ruin a lot of suits and blouses. Can't have that. ;)
"Largest" is just straight-up a false claim. [Solar Impulse](https://en.wikipedia.org/wiki/Solar_Impulse) and [Helios](https://en.wikipedia.org/wiki/AeroVironment_Helios_Prototype...) were electric and had over double the wingspan, just to name a few of the ~dozen examples.
Heart's engineers should be proud of this genuinely impressive accomplishment, but they need to rein in whoever is writing their PR pieces.
Largest in terms of takeoff weight. Wingspan is a pretty meaningless metric for "largest aircraft". By that logic the planes you linked are larger than a 737.
See also: Boston and NYC to Cape Cod and the Hamptons.
The electric/green angle helps with these kinds of routes too.
It's about feeding the existing network. Millions of people in the US live in places a 2+hr drive to the nearest major airport, but have plenty of smaller municipal fields nearby. Electric aviation could finally make it profitable and cheap enough to run those routes. It also opens the door to true commuter aviation becoming a thing, when you can offer short flights for the cost comparable to a train ticket, and operate out of small fields with small planes multiple times a day and no need for the whole TSA experience.
If its >2 hour drive to the airport this plane probably isn't going to take you there on pure-electric power, that's my point. If you drive 65MPH for two hours, you've gone further than this thing can fly (on pure battery).
Booze Cruise aka "Winetasting" for the tech crowd
Fly sustainable, guzzle some fermented bio grapes, ...
I'm mostly just wondering why they're making such a big point talking about this being a battery electric plane when the actual commercial variant they hope to sell will likely be mostly used like a plug-in hybrid (I'd imagine).
> The ES-30 is a conventional fixed-wing, 30-seat hybrid-electric regional airliner
https://investors.beta.team/news-events/press-releases/detai...
By comparison, a regular regional jet probably has around 40 MWh of energy in jet fuel.
Even if the batteries could be made entirely inert, the ability to deliver a plane sized slug of kinetic energy to a building of your choice retains most of the danger.
Even if that could be avoided, a plane must remain operational enough throughout all flights to avoid falling out of the sky.
It would take a large bomb to take out a whole bus load of passengers, a very small one to put safety critical systems of a plane out of action.
As much as I would appreciate this happening, I don't think electric planes are going to make it happen.
Nit: a lithium ion battery fire isn't a lithium fire, it's the electrolyte. Lithium ion batteries don't use elemental lithium. Thankfully.
Even without the jet fuel on board, the destruction would still have been substantial. Whether the Twin Towers would have fallen without the fuel is not really relevant.
Most of the security is security theater. The primary improvements to security have not been people taking their shoes off or emptying water bottles. It was locking the cockpit doors and passengers knowing that they cannot rely on the hijacker wanting to survive. Other than that, making sure passengers are on board if their luggage is has meant no more Lockerbies.
All the other stuff is pretty much a waste of time.
It would really suck to have to go through security after your first flight whenever you are connecting.
Plus, depending on the battery chemistry, that material could also create a serious fire; it is a lot of stored energy either way.
So, I would not wait for it
Also, I'm not so sure the passengers involved would be thrilled at your suggestion.
Gasoline on the other hand …
VTOL have other advantages of course in terms of operational flexibility, but where there's existing airfields, fixed electric would be more efficient
Also, at the size/scale of this aircraft (thirty passengers) any type of VTOL wouldd be even less practical
But a way worse record when compared to the fixed-wing C-130.
Both comparisons are per 100k flight hours.
Some of that risk can possibly be mitigated with a rotating engine, but fixed wing, similar to the Bell Valor. Possibly, because AFAIK, the Valor is the only plane like this and it's just a PoC.
Your DEN to COS suggestion would probably be quite popular for skiers coming in that want to avoid renting a car and would enjoy the electric hop to avoid a 2hr drive.
The real winning route would be two airports separated by ~100miles that still have a 3+hr drive, or two small regional airports where security time is negligible (that's certainly NOT O'hare, in my experience at least lol) Flights leaving GRB to northern Michigan would be perfect for this though since the alternative is to drive around Lake Michigan.
ORD to MKE is reasonable as part of a X -> ORD -> MKE one stop; at least when I was using MKE, I'd always need a stop (Midwest was too expensive for me) and ORD was an option, although I think I always went through DFW or PHX.
Yes, bit less than half, but anyway that is exactly why I said takeoff would be the peak power output.
> that’s why airplane engines are rebuilt every few thousand hours vs lasting hundreds of thousands of miles (tens of thousands of hours) for a car engine that only uses a small fraction of its power to keep a car moving.
Ratio of max power to average power is very low on the list of reasons why a gas turbine engined plane needs maintenance more frequently than a piston engined car.
I meant for the comparison to be between an internal combustion engine in a car and an air-cooled piston engine in a plane, I should’ve clarified in my post.
I’m amazed we even figured out how to make reliable gas turbines (single crystal blades still astound me) so any required maintenance makes sense, they operate at the edge of engineering in a way that most machines don’t.
I use Mogas in my plane and even that is painful these days
Not saying a parachute couldn't be designed to work, but there isn't an existing option today.
When you add sources like solar onto the grid, you end up with times of the day where high solar production pushes base load power generators to need to slow down or shutdown.
Sounds like a great deal right? But now you’re on the hook for receiving and storing that oil. That costs money, it’s not free. That’s why the price went negative - the seller was trying to offload and there were no takers at $0.
I'm not sure I understood this sentence?
On an electric grid, Supply and Demand must meet. When demand is low, you either reduce supply or increase demand and sometimes it's easier to increase demand.
Also, if you're supplying electricity, you may have reason to supply it even when the wholesale cost is negative. If you have production incentives not included in the wholesale price, you can be profitable at negative wholesale prices. (Things like green incentives, or base load incentives, or long term supply price guarantees)
If significantly reducing your output takes time or causes operational difficulties, it may be sensible to deliver at negative prices as you taper off. If you have a fuel shipment inbound and nowhere to store it, the negative wholesale price may be less expensive than cost to deal with the storage logistics.
Oh, even better, you're always going to have enough propeller power to take off. Extremely high power-density batteries on a glider which detaches at cruising altitude and flies back to the airport? Oh, you fly even higher than normal before detaching to transfer even more energy into PE?
Hmm, shouldn't electric be able to fly even higher? But they're short range, so probably not worth it ... yet.
But it's all on the ground.
The airframes would have be heavier, beefed up to take that load. FWIW, the Navy version of the F-35 weighs ~5000lbs more than the AF version's 29000 dry weight (granted, that's also additional folding wing changes). It also costs about 20% more per unit.
Anyways, it's all certainly possible. Just impractical without a real need.
But catapult launch ballistic passenger gliders would be pretty cool.
Airport crew could do it based on calculated weight comunicated by pilots. With current technology it could even be automated - pull the airplane 10 m at a fixed (low) power setting, determine how fast it accelerated, calculate mass, increase power accordingly for the rest of the takeoff distance. Even an Arduino could do it.
Or simply apply the maximum force supported by the airplane's attachment point (front landing gear) no matter what the weight is.
Airframes would probably not need much strenghtening. I expect that the forces from wheel breaks are aprox. the same.
PS: With a catapult / winch launch, the MTOW could probably be increased a little - more passengers and cargo for the same flight costs.
But realistically you're either imparting 2G and hurting 10% of the passengers, or you may as well not bother with one. The "JATO-like" solution of a modular prop+battery unit giving you a takeoff+climb boost for 10 minutes and then heading back to the airport seems less objectionable.
My local airport is so freaking annoying with all the Cessnas flying over our heads. I can't wait for electric to be the better choice.
I don't think most pilots realize how annoying they are in disturbing the peace.
I think pilots are of a similar mindset. New airfields are rarely built near populated areas, so what usually happens is that nearby land gets developed, people move there, then they try to get the airfield restricted or shut down. It's a similar story for other noisy businesses like outdoor gun ranges or race tracks. I can see how that creates resentment for those who enjoy such hobbies. They're probably thinking something like, "We were here first. Why should we have to change or leave?"
I do dislike that leaded gasoline is still common in general aviation, so I look forward to a future full of electric aircraft.
Denvers original airport was built in the "middle of no where", for noise reasons. Continue on for 30 years and lots of housing built up around it. People start complaining about noise. City decides to move the airport. Moves it 30 miles away, in the middle of no where (now DIA). Yep, you guessed it. People start building close to the airport, and then complain about the noise. I fully expect it to move again in 15-20 years
Oh no, there are all these old engine that can't use unleaded gas. The hobby pilots just have no choice but to continually dust the surrounding area with lead vapors. They certainly can't be forced to update their engines/aircraft. Cry me a river.
But, regardless, it's actually shorter than I thought! Although 1G forward acceleration is still quite a bit. Imagine elderly passengers with osteoporosis... and the lawsuits.
I know there's some level of caveat emptor when buying a house, and realtors are guaranteed to not have any showings when it's noisy, but maybe just spell it out and the purchaser needs to be made aware.
“I swear, the race track just materialized out of nowhere!” -A wealthy liar living in California
I assume it was dismissed immediately since Laguna Seca is almost 70 years old.