Electric powered flight...probably best for blimps.
Electric Planes Usher in the Second Great Age of Aviation
11–20 of 70 posts
Re: Electric Planes Usher in the Second Great Age of Aviation
#12They could at least mention Hyrdogen fuel cell powered aircraft
Re: Electric Planes Usher in the Second Great Age of Aviation
#13Reminds me of a german startup that designs a vertical takeoff and landing, two seated electric plane with an interesting form factor: http://lilium-aviation.com/
[Edit: no affiliation]
Re: Electric Planes Usher in the Second Great Age of Aviation
#14I read a piece by Elon Musk, who was saying that electric planes - whilst very far away - are the future of air travel. Why? Because they will allow planes to fly higher - increasing efficiency and speed. Apparently the normal 30,000 feet cruising altitude is not higher because the reduced oxygen levels at higher altitudes impact the gasoline combustion too much. Even at 30,000 feet the air is thick as soup at cruisi…
> I read a piece by Elon Musk, who was saying that electric planes - whilst very far away - are the future of air travel. Why? Because they will allow planes to fly higher - increasing efficiency and speed. That's a meaningless/nonsensical assertion. If we're going to ignore basically everything we can also state that nuclear is the future of air travel (and that's actually a more sensible statement, nuclear fuel has…
I'm not sure it's ignoring everything - as this article states, electric planes exist today, and are improving at a fast rate. Batteries are also improving (thanks to Musk and others), not that electric planes needs to be battery based - fuel cells could be the answer (though presumably these require oxygen so might have altitude issues). So whilst far away, it's an extrapolation from our current position.
Nuclear planes don't exist today in any form, and would have major safety concerns no doubt (any accident would be pretty catastrophic)
Re: Electric Planes Usher in the Second Great Age of Aviation
#15Earlier quoted context omitted.
Surely the landing gear, wing spar attachments, and brakes all have to be able to cope with an unexpected turnback and landing with most of the original weight? (not to mention heavy landings in adverse weather conditions)
No see http://www.caa.co.uk/default.aspx?catid=60&pagetype=90&pagei... or http://www.boeing.com/commercial/aeromagazine/articles/qtr_3... They are only certified to the maximum landing weight which typically is lower than the maximum takeoff weight. When an overweight landing (ie. the weight is higher then maximum landing weight) occurs engineers have to perform a thorough inspection of the plane structure - landing…
> the maximum landing weight which typically is larger than the maximum takeoff weight.
I assume this was a typo and you mean that the max landing weight is typically less than the max takeoff weight.
Re: Electric Planes Usher in the Second Great Age of Aviation
#16Earlier quoted context omitted.
> I read a piece by Elon Musk, who was saying that electric planes - whilst very far away - are the future of air travel. Why? Because they will allow planes to fly higher - increasing efficiency and speed. That's a meaningless/nonsensical assertion. If we're going to ignore basically everything we can also state that nuclear is the future of air travel (and that's actually a more sensible statement, nuclear fuel has…
I'm not sure it's ignoring everything - as this article states, electric planes exist today, and are improving at a fast rate. Batteries are also improving (thanks to Musk and others), not that electric planes needs to be battery based - fuel cells could be the answer (though presumably these require oxygen so might have altitude issues). So whilst far away, it's an extrapolation from our current position. Nuclear pl…
> I'm not sure it's ignoring everything - as this article states, electric planes exist today
Prop toys exist, not "future of aviation" anything. Props being an other issue, electric planes means no turbofans.
> Batteries are also improving
Batteries are not improving at a rate which would increase their specific energy by 2 orders of magnitude (the difference between the specific energy of the best batteries available today and bog-standard jet fuel) in any sort of interesting timescale. And that's before considering environmental issues, most batteries don't appreciates temperatures of -20C and below.
> thanks to Musk
That's a joke right? Tesla's battery innovations are related to manufacturing efficiency and structural sharing.
> So whilst far away, it's an extrapolation from our current position.
It's not extrapolation it's daydreaming based on what is basically magical thinking. It's less of an extrapolation than dyson spheres are.
> Nuclear planes don't exist today in any form
Nuclear planes were demonstrably feasible (if not necessarily smart) in the 60s: https://en.wikipedia.org/wiki/Tupolev_Tu-95LAL
Re: Electric Planes Usher in the Second Great Age of Aviation
#17I drive an electric car and fly piston airplanes. I don't see electrics replacing internal combustion in aviation in my flying lifetime. Why? Weight. The specific energy (energy per kg, edited per masklinn) of batteries sadly lags the specific energy of gasoline or kerosene, and the airplane carries that weight for the whole flight for an electric airplane. (My gas airplane gets lighter and lands as much as 1000 poun…
I entered the Local Motors and ARPA-E contest for the Lightweight Sedan challenge and proposed a three part method to reduce weight: Revised chassis, bio-composite materials, and a hybrid drivetrain using micro-turbines to produce electricity to power the vehicle. The contest parameters stressed that the proposal should be "research for the next 10 years." So, I cited the efficiency and extremely light-weight of micro turbines to piston engines, and postulated that increasing technology in battery / KERS systems would compliment the real-world application in time.
Needless to say, I was ridiculously mad when I saw that the winning entries were 1) an aerodynamic proposal based on an exoskeleton, 2) replacing body panels with a new metallurgy compound, and some other thing that I can't recall right now. None of them really addressed the contest parameters. It basically made me swear off any more Local Motors participation.
Anyway, the bright side is that I get to maintain all rights to my entry / materials, so one day, I just might have a chance to develop a concept based on these principles and show ARPA-E and Local Motors what they missed. I guess this is how Ferruccio Lamborghini must have felt at first. Sigh.
Re: Electric Planes Usher in the Second Great Age of Aviation
#18I drive an electric car and fly piston airplanes. I don't see electrics replacing internal combustion in aviation in my flying lifetime. Why? Weight. The specific energy (energy per kg, edited per masklinn) of batteries sadly lags the specific energy of gasoline or kerosene, and the airplane carries that weight for the whole flight for an electric airplane. (My gas airplane gets lighter and lands as much as 1000 poun…
I think we might see gasoline/jet-A over electric airplanes, perhaps with or without battery storage. That would allow a few neat optimizations. You'd have more control over CG. You could have a smaller high efficiency engine that always ran at peak efficiency (or an IC engine with several modes). You could have more control over noise in urban areas. With a battery for peak/boost power, you could have a tiny engine which could supply cruise plus accessory power and use battery-backed boost for takeoff/climb. Engines that are replaceable in a few hours. All kinds of good things could happen.
>Many airplanes are certified for a ramp, taxi, and takeoff weight higher than their approved landing weight.
Is that common in G/A aircraft?
In any case, I'd love to see a tech. revolution in GA powerplants. I've grown tired of having quaint old 1950's era tractor engines be the dominant technology.
Re: Electric Planes Usher in the Second Great Age of Aviation
#19I drive an electric car and fly piston airplanes. I don't see electrics replacing internal combustion in aviation in my flying lifetime. Why? Weight. The specific energy (energy per kg, edited per masklinn) of batteries sadly lags the specific energy of gasoline or kerosene, and the airplane carries that weight for the whole flight for an electric airplane. (My gas airplane gets lighter and lands as much as 1000 poun…
A fuel cell that carries only hydrogen and harvests oxygen from the atmosphere ... is viable. *
*the whole membrane degradation thing excluded
Re: Electric Planes Usher in the Second Great Age of Aviation
#20I read a piece by Elon Musk, who was saying that electric planes - whilst very far away - are the future of air travel. Why? Because they will allow planes to fly higher - increasing efficiency and speed. Apparently the normal 30,000 feet cruising altitude is not higher because the reduced oxygen levels at higher altitudes impact the gasoline combustion too much. Even at 30,000 feet the air is thick as soup at cruisi…
Like most, I originally assumed that because batteries have poor specific energy compared to fossil fuels, there was no point in considering them for aircraft.
But Musk's assertion has made me reconsider. Has anyone here done the math? What I think he's talking about is NOT a conventional plane with a battery simply replacing the gas tank, but instead essentially a flying battery, where 90% of the plane's mass is battery.
This sounds ridiculous at first, but when you consider how cheap electricity is compared to jet fuel, as well as the other benefits the OP mentioned, there might be something to it (for short-haul flights.)