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Airplanes that fly on electricity debut at Fresno’s Chandler Airport
- ohazi 9y agoThe airplane in question is a Pipistrel Alpha Electro, which has been around since 2015.
- Patrax 9y agoNot cool how they frame the story to make it sound like the municipalities in question were responsible for making the plane.
- briandear 9y agoAgreed! They didn’t even mention the manufacturer of the airplane but mentioned the relevant government initiative at least twice. Reads like a city hall press release.
- derefr 9y agoConsidering how hard it is to get new technologies pushed through municipal red tape, the framing of this as a “city hall press release” was likely the manufacturer’s idea, part of a deal they made in exchange for some consideration for changing municipal airspace regulations to allow testing. See also: driverless cars.
- correnos 9y agoMunicipalities don't have airspace regulations. That's all managed federally. Also the Alpha Electro is already legal to test. It's apparently registered as an Experimental aircraft in the US currently, which means it can be used by owners but not commercially (e.g. for flight training). The market Pipistrel's aiming for is the Light Sport Aircraft category, but electric planes can't be registered as LSA in the US so Pipistrel would have to go through the standard airworthiness certification process. Which is long and expensive.
- wpietri 9y agoFor the curious: https://www.pipistrel.si/plane/alpha-electro/overview https://www.pipistrel.si/plane/alpha-electro/overview I note it has "up to 60 minutes" under "endurance". What I believe is the non-electric version of the plane is here: https://www.pipistrel.si/plane/alpha-trainer/overview https://www.pipistrel.si/plane/alpha-trainer/overview That has an endurance of 3.1 hours with its standard 50-liter fuel tanks.
- greglindahl 9y agoYep. Similar to cars, electric planes are starting with short ranges. The huge savings is in maintenance.
- minitoar 9y agoAlso, 30 minutes is long enough to just do a few take offs and landings to stay current on the cheap, or just for doing short lessons or flight reviews. I could definitely see a flight school having one of these around just to meet those needs as cheaply as possible.
- ythn 9y ago> The planes are zero emission aircraft running on lithium ion batteries How heavy is that battery pack??
- derefr 9y agoWhy is it that we use heavy solid/liquid electrolytes, anyway? It seems that gaseous electrolytes are possible; in an environment where volume doesn’t matter nearly as much as weight, wouldn’t a battery built on such an electrolyte be an obvious choice?
- ggg9990 9y agoThe volume would be insanely high. Like blimp sized.
- haroldl 9y agoNot there yet, but yes, people are thinking about this: https://en.wikipedia.org/wiki/Lithium%E2%80%93air_battery https://en.wikipedia.org/wiki/Lithium%E2%80%93air_battery
- dredmorbius 9y agoMetal-air batteries gain mass as they discharge. Non-ideal for aviation.
- rainbowmverse 9y agohttps://en.wikipedia.org/wiki/Pipistrel_Alpha_Trainer#Alpha_Electro https://en.wikipedia.org/wiki/Pipistrel_Alpha_Trainer#Alpha_... >> Pipistrel introduced an electric version called the Alpha Electro in 2015 at a price of 69,000 euros,[3] with technology from the Pipistrel WATTsUP proof of concept design, for short training. It has energy for one flight hour plus reserves, and can recharge in 45 minutes or have its batteries replaced in 5 minutes.[4] Instead of 78 lb (35.5 kg) of fuel, it has 277 pounds (126 kg) of LiPo cells, however the water cooled electric motor weighs 11 kg;[5] much less than the gasoline engine. It has a useful load of 380 lb, whereas a Cessna 152 has between 350-480 lb useful load.[6][7]
- 9y ago
- briandear 9y agoThey mention it is for flight training but a big part of flight training is fuel mixture/engine management. It would be interesting if someone were to train for their pilot license in this if they would be type restricted to only electric aircraft.
- djrogers 9y ago> a big part of flight training is fuel mixture/engine management. When I was taking my private pilot lessons, this was a very minor thing - maybe a couple of minutes spent on it every other flight? The only time we spent more than a couple of seconds adjusting the fuel/air mixture was when we were intentionally stalling the engine to practice recovery procedures. And with a private pilot's license, before you would be allowed to rent any plane you generally have to show you've been checked off in one - that's one of the things your log book shows.
- verelo 9y agoAgreed it’s a thing, but rather small compared to the many other complex tasks required to fly a plane.
- tr352 9y ago> intentionally stalling the engine to practice recovery procedures Are you talking about stalling the aircraft or stalling the engine? As far as I know, intentionally shutting down the engine is considered too dangerous for PPL training purposes. Whenever a zero power situation is practiced (e.g. aerodynamic stall or simulated engine failure) it's done with idle power.
- audunw 9y ago> but a big part of flight training is fuel mixture/engine management. But aren't most pilots ultimately training to fly turbofan or turboprop planes? Is fuel mixture and engine management for a piston-engine plane relevant to that? I'd imagine that the jump from electric to larger planes is not much bigger than from a piston-engine flight training plane. But I'm not a pilot so I'm just speculating here. Regardless, I'm sure it's easier to do everything but engine management first, and then do fewer sessions with just focus on engine management.
- netgusto 9y agoAlso: A DIY electric airplane made by a hobbyist (Peter Sripol; check his channel out) https://www.youtube.com/watch?v=eNSN6qet1kE https://www.youtube.com/watch?v=eNSN6qet1kE The 7 parts build footage : https://www.youtube.com/watch?v=KidFSfdb8t8 https://www.youtube.com/watch?v=KidFSfdb8t8
- btreecat 9y agoSuch a fun series to watch too. The evolution of the engineering is interesting and educational. I look forward to him tinkering with it some more. Hopefully he brings it out to this years FlightFest and I can see it in person.
- ahelwer 9y agoAirplanes are beautiful dreams.
- jcims 9y agoI've only seen Peter in his guest spots on Flite Test. One of the sweetest and coolest dudes on that channel. Always down to experiment and obviously thinks big. Edit: Case in point, magnus effect plane - https://www.youtube.com/watch?v=K6geOms33Dk https://www.youtube.com/watch?v=K6geOms33Dk
- phkahler 9y agoFor electric planes I'd like to see dual battery dual inverter/motor twin props for redundancy. Sure I trust a good electric more than gas, but why not offer more than just that?
- dschuler 9y agoMulti-engine planes are more complex to fly and require a different license. If an engine quits during takeoff, the plane is going to yaw toward the failed engine side, among many other issues. The plane doesn't just fall out of the sky when the only engine quits, anyway - you can glide quite some distance, provided you've got the altitude to do it.
- dmurray 9y agoI never really understood this. Sure, it's complicated to compensate for asymmetric thrust. But if you know how to fly a single-engine plane with no engines, surely you can figure out a two-engine plane with one engine? At worst you can turn off the functioning engine and be back in the situation you understand.
- dschuler 9y agoThe FAA publishes a couple of books, including the Airplane Flying Handbook [0], that has a good intro chapter to multi-engine flying [1] that goes into some of the issues that come up. [0] https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/airplane_handbook/media/airplane_flying_handbook.pdf https://www.faa.gov/regulations_policies/handbooks_manuals/a... [1] https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/airplane_handbook/media/14_afh_ch12.pdf https://www.faa.gov/regulations_policies/handbooks_manuals/a...
- phkahler 9y agoIf you put them in back closer to the centerline it helps minimize that yaw and roll tendency. On the other hand, I picture one on each wing to minimize the length of cable needed to deliver the current. Cables for 100-400A add a couple pounds per foot.
- cyanoacry 9y agoMore relevant information (including the history of the project) from AOPA: https://www.aopa.org/news-and-media/all-news/2016/october/19/electric-aviation-made-practical https://www.aopa.org/news-and-media/all-news/2016/october/19...
- thrill 9y agoBye Aerospace's electric Sun Flyer made its first flight last week also. http://sunflyer.com/ http://sunflyer.com/
- walrus01 9y agoLooks a lot like a Cirrus SR20. But I imagine that for aerodynamics and efficiency reasons, 2 to 4-seat sized, fixed gear, low wing, light aircraft will generally converge on a similar design approach.
- ghostbrainalpha 9y agoSerious question: If a plane runs on electricity, would it ever make sense to put solar panels on top of it to try and get extra range? Or is the scale so off that solar panels can't meaningfully contribute?
- DiffEq 9y agoThey would not meaningfully contribute.
- Kelbit 9y agoQuick back of the envelope calculation: Wing area of a Cessna 172 (representative GA aircraft) is 16 m^2. Best-case insolation on a sunny day with no clouds at high noon is around 1000 W/m^2. Best commercially available solar cells are the triple-junction cells used on commercial satellites, at about 30% efficient. They are horrendously expensive (around $50-100k per square meter), but we will ignore economics for now. 16 m^2 * 1000 W m^2 * 0.3 = 4.8 kW. Powerplant for a Cessna 173 is a 160 hp piston engine, or 120 kW. So, we're about an order of magnitude and a half off. The cells also aren't massless, so they will add weight and reduce range... you'd need to do a cost/benefit there. There are a couple solar UAVs in existence (example: https://en.wikipedia.org/wiki/Qinetiq_Zephyr https://en.wikipedia.org/wiki/Qinetiq_Zephyr) which use super lightweight materials and have very large wing areas to support solar cells. Even then, they are really on the hairy edge of where physics works in your favor.
- mrfusion 9y agoDoes it use the full 160hp while cruising though? I’d imagine most of that peak power is for take off.
- plantain 9y agoMost of it is still used while cruising. 100hp+ depending on cruise speed. The excess power for climb is very small, which is why weight/loading is so critical in aviation.
- alabut 9y agoThe embedded video is super short, so here's a longer piece by a youtuber that spent some time with the same model when they hit Australia: https://www.youtube.com/watch?v=2CS3isCH4bk https://www.youtube.com/watch?v=2CS3isCH4bk
- walrus01 9y agoI was just about to post this same video. The trouble they had with the big generator at the field site was interesting. I imagine that like a Tesla it can charge from a 120VAC 15A (or euro/world 230-240V, 10A circuit) overnight, but it will be much, much slower to reach full capacity. It's good that they honestly state the limitations that it's best suited for flight training applications where it will always return to the same field. Imagine trying to fly that thing from Perth to Adelaide in individual 50-minute hops between outback airfields... Impossible.
- alabut 9y agoYeah, the reality check in that video was eye opening. Clearly it’s a deliberate strategy to roll these things out at flight schools at first, so they’re always circling within landing range. Electric planes will definitely graduate to short hop commutes eventually though and not just be niche training vehicles, especially when you consider how much safer they are than jet engines: they have way less moving parts, require less maintenance, and most importantly, they don’t stress the airframe nearly as much. And that’s just with current airplane designs retrofitted for electric (which is essentially what these training planes are) instead of the upcoming designs that are built with many small electric motors and not the giant jet engines. Lilium is an example of the new style of electric plane, with motors distributed through the wing: https://www.youtube.com/watch?v=ohig71bwRUE https://www.youtube.com/watch?v=ohig71bwRUE
- psergeant 9y agoHopefully they’ll be quieter, too; noise pollution from planes is a big deal, and avoiding it creates congestion and all sorts of other costs
- gene-h 9y agoHydrogen offers better prospects for civil aviation than batteries do. Airbus did a study[0] that showed it would be possible to power all civil aviation use cases with cryogenic hydrogen. They even showed that in the near term existing aircraft could be modified to run off of hydrogen for short and medium range. Getting longer ranges would require new aircraft though. They also believe that we could see short range and medium range hydrogen powered aircraft introduced as early as 2015. Of course it's 2018 and this hasn't happened, possibly due to the cost of producing hydrogen. [0]http://www.fzt.haw-hamburg.de/pers/Scholz/dglr/hh/text_2004_02_26_Cryoplane.pdf http://www.fzt.haw-hamburg.de/pers/Scholz/dglr/hh/text_2004_...
- oh_sigh 9y ago> possibly due to the cost of producing hydrogen. Cursory googling claims you can generate hydrogen for $28/million-BTU with electricity @ 5c/kwh. 1 million BTU is about 8 gallons worth of jet fuel, so I would guess that jet fuel is much cheaper than $4/gallon?
- kingnothing 9y agoThe nationwide average for Jet A is $4.53 / gal https://www.airnav.com/fuel/report.html https://www.airnav.com/fuel/report.html
- asdfadsfgfdda 9y agoAirlines pay much less for jet A than FBO prices, probably closer to $2/gal (https://www.eia.gov/dnav/pet/hist/eer_epjk_pf4_rgc_dpgD.htm https://www.eia.gov/dnav/pet/hist/eer_epjk_pf4_rgc_dpgD.htm).
- Hextinium 9y agoCost runs actually about the same, jet fuel is about $5 dollars a gallon probably cheaper wholesale the issue comes from even though hydrogen produces more 3x energy per kg than jet fuel the energy density is 3x less per unit volume. Meaning you would need bigger fuel tanks per distance travelled which would require modifying the airframe to be bigger in addition to having to add insulation.
- John_KZ 9y agoHow loud is it?
- taneq 9y agoNot too different to a normal light aircraft, although maybe a bit quieter. Most of the sound you hear from them is prop noise.
- inamberclad 9y agoAnyone else surprised that the sponsors of this project are the local cities?
- Pseudothink 9y agoIs one of these Elon Musk's electric jet? https://www.youtube.com/watch?v=EuG2AVFB-g0 https://www.youtube.com/watch?v=EuG2AVFB-g0
- icodeallnight 9y agoOne of my friends has the Alpha Electro. It's an amazing airplane. I've had the awesome experience of flying it with him. Definitely excited for the future of flight. Here are some videos of him flying it: part 1: https://www.youtube.com/watch?v=ljbhGfnUchA https://www.youtube.com/watch?v=ljbhGfnUchA part 2: https://www.youtube.com/watch?v=1o6WWQQQot0 https://www.youtube.com/watch?v=1o6WWQQQot0 part 3: https://www.youtube.com/watch?v=1URqmuJ2Tbg https://www.youtube.com/watch?v=1URqmuJ2Tbg part 4: https://www.youtube.com/watch?v=GPoXSItKELQ https://www.youtube.com/watch?v=GPoXSItKELQ