First Fully Electric Manned Helicopter Flight 86
cylonlover writes "On August 12, electrical/aerospace engineer and helicopter pilot Pascal Chretien took to the sky in the world's first untethered, fully electric manned helicopter flight in a prototype machine that he designed and built almost entirely by himself within a 12-month development period. In his 2-minute, 10-second test flight, Chretien beat aviation giant Sikorsky into the record books — but it was not without significant risk. As the man himself puts it: 'in case of crash I stand good chances to end up in kebab form.'"
good but not enough. (Score:1)
Re: (Score:3, Informative)
Re: (Score:1)
Reduced noise is a second advantage of the configuration - part of the loud 'slapping' noise associated with conventional helicopters arises from interaction between the airflows from the main and tail rotors, which in some designs can be severe.
http://en.wikipedia.org/wiki/Coaxial_rotors#Other_benefits [wikipedia.org]
Re: (Score:2)
NOTAR [wikimedia.org] works better. Fans can be much quieter, and this leaves you with only one large rotor.
Re: (Score:3)
There's no way to make a quiet helicopter. The sound comes from the rotors mainly, not the engine, and there's no way to quiet the sound of what's basically a giant fan that's powerful to lift itself and several thousand pounds of vehicle and passengers/cargo into the air.
The chopping sound you hear from many helicopters is an interaction between the tail rotor and the main rotor. This can be eliminated or reduced in various ways, such as with the NOTAR design which simply has no tail rotor (it uses a dif
Re: (Score:2)
Re: (Score:2)
Again, a 12-inch rotor diameter isn't going to carry much, probably not even enough for a handgun. Those little R/C helicopters are all made out of styrofoam for a reason. You'll have to increase the rotor diameter to carry enough weight for a decent UAV, but then your noise is going to go way up along with it.
Wow.... (Score:5, Funny)
Re: (Score:3)
Haha I was following Sikorsky's efforts, they put bleeding-edge batteries into a proper helicopter airframe, spent who knows how much to have the first electric helicopter.
And this guys beats them to it with his little hacked-up whirlygig that looks like it was made of old government school chair frames and tracing paper.
That's the ultimate Frosty Piss right there. You hear that trolls? None of you will ever be as good as this guy.
Re:Wow.... (Score:4, Insightful)
I haven't read TFA yet, but there's probably a difference in goals here: a fully-electric helicopter at the lowest possible cost, vs. a fully-electric helicopter that's actually somewhat usable for the things you'd normally use a helicopter for.
With enough time, I could put together a homebrew electric helicopter that lifts me up in a lawn chair, but what good is that? All it does is prove a concept, but I could have told you before that such a thing is perfectly possible, and you don't need to actually go to any effort to prove it. Unless you can actually lift a significant amount of weight, and have an airframe that meets various regulations, has all the required instruments, has the required measure of crash protection (normal helicopters actually do have a certain amount of crashworthiness, to prevent needless deaths from low-speed crashes near the ground, such as from "hard landings" and other accidents that occur before the craft has reached any altitude), has all the required lights, and can perform within a sufficient envelope, then it's fairly pointless to build something like this.
Converting any fossil-fuel-powered vehicle to electric power isn't rocket science. There really isn't that much to it: you get rid of the piston/turbine engine, stick an electric motor in its place (there's a lot of different kinds of motors however and I'll avoid getting into that), and then most importantly, you put in enough batteries to hold the power you'll need for that motor. That last part is the hard one, because right now we simply don't have batteries capable of coming close to the energy density offered by a fuel tank full of gasoline, diesel, or kerosene. The motor part is easy; we've had great electric motors for a long time, and the brushless-DC motor technology we have now is simply fantastic, but without a way of storing enough electricity to make them usable, it's all for naught.
It's worse in a helicopter however than in a car. In a car, weight isn't that much of a factor (since it doesn't have to lift itself off the ground, after all), so a few hundred pounds of batteries can be a perfectly acceptable tradeoff in light of the fact that gas engines waste a lot of fuel by being oversized for their applications (a car engine has to be sized for its peak load, not its average load, and accelerating from a stoplight requires much more power than simply cruising at 55, but the bigger the engine, the bigger the frictional and pumping losses). In an aircraft, engines aren't oversized for peak loads; in helicopters, they're always run at 100% of their rated rpm. So with converting a car to electric drive, you get to improve your efficiency by the fact that most of the time, you only need 10-20 HP or so to maintain your speed, and you only drain that much energy from your batteries and don't suffer any significant loss of efficiency by having an electric motor that can deliver 150 HP when it needs to. But with a helicopter, you have to run it at 200HP (or whatever; that's what a small 2-seat training helicopter would need; something that can hold 6 people would need more like 1000+) constantly, from the time you lift off until you touch down. That's a LOT of energy to store in batteries, and is quite frankly beyond our technology.
Re: (Score:2)
Make it cheap enough and toss in a networked autopilot, electric copters could replace the family sedan.
Suburbia would be filled with the sound of a thousand angry bees every morning.
Re: (Score:2)
Re: (Score:3)
Fuel taxes are not how the FAA is funded. You sir suck at sarcasm.
The rest of your pathetic attempt failed just as poorly.
Re: (Score:2)
Re: (Score:3)
You can't build electric helicopters. The battery technology does not exist to make viable electric helicopters. Some silly toy that someone built in his garage that has a 2-minute flying time (or whatever) is not a replacement for a real helicopter, any more than this [youtube.com] is a replacement for a normal car.
Re: (Score:2)
While this is certainly novel and interesting... (Score:1)
It will end up a curiosity since it has no real world application. Helicopters consume vast amounts of energy just to stay aloft, much less get any work done.
Just like the electric float plane featured ob /. it simply wont scale. The laws of physics and thermodynamics simply cannot be ignored.
Mass will always be a factor until we figure out an anti-gravity field or some other star treckian device to reduce our apparent mass we simply cannot get enough energy out of today's batteries or fuel cells -v- thei
Re: (Score:2)
The laws of physics still have room for at least a 10-fold improvement in battery technology compared to current commercially available batteries. Of course this helicopter is a curiosity, it would be a curiosity even if it was powered by a conventional engine! It isn't exactly something you could use for commercial flights.
I would expect to see electric private planes to become popular within 10 years (popular within the small community which has private planes anyway) and perhaps another 10 years before i
Re: (Score:3)
The energy density of the battery is 0.576 MJ/kg. The energy density of kerosene type BP Jet A-1, 43.15 MJ/kg. To get the same energy density the battery would have to be 74 times as efficient. That is a bit of a stretch for batteries.
Did you also notice that the helicopter was flown in ground effect which decreases the energy required. One would think he would have tried an endurance test to see how the batteries stood up. 130 second is not a long flight.
Re:While this is certainly novel and interesting.. (Score:5, Informative)
Energy density for lithium air is 18.8MJ/kg, if you have to carry the oxygen with you. Twice that at take off if you use atmospheric air. 9MJ/kg including oxygen has been achieved in the lab. Not 43MJ/kg, certainly, but you are lucky to get a third of that energy out with helicopter engines and the engines or turbines are quite heavy.
Yes, the particular electric helicopter from TFA is all fun and games and doesn't have a future. Nothing wrong with a bit of fun and games.
Re: (Score:2)
Hah you probably would have said all the same things if you were alive in the age of the Wright Brothers, and you would have been equally wrong for all the same reasons.
Re: (Score:2)
Re: (Score:3)
Or you can wait ten years. By that time, the Wright Brothers' kite already transformed into viable planes with much longer ranges and speeds. Let's see if it happens with electric helicopters.
Let me save you ten years: won't happen.
Well, it might happen, but it won't be because anyone built electric-powered aircraft, it'll be because someone completely disconnected from the aviation industry worked away in a lab experimenting with battery chemistries and different materials (such as nanotubes) until they fo
Re: (Score:2)
Wow, you really believe that? It isn't 1922 anymore. You can't make breakthoughs in the physical/chemical world in a garage anymore.
Where did I say anything about a garage, or about a single person?
Let me repeat what I wrote before:
"it'll be because someone completely disconnected from the aviation industry worked away in a lab experimenting with battery chemistries and different materials (such as nanotubes) until they found something that worked and provided the required energy density."
Maybe the "someone
Re: (Score:2)
The requirements for aircraft and car batteries are different. Aircraft motors run at a pretty constant speed. Cars are constantly accelerating, decelerating and braking (which on the more advanced EVs means a little recharging). Also if a car battery fails, that's annoying. If an aircraft battery fails, that may be fatal.
In both cases you want the lightest battery given the usage profile. And that means different for those two applications.
And mobile phone and laptop batteries are different again.
Sure, the
Re: (Score:2)
I'm a Space Nutter now because I'm pro-space-exploration? Even though I've made arguments in the past for unmanned rather than manned space travel and made demonstrations that it wouldn't be economically viable to collect watermelon-sized diamonds from the surface of Mars? Wow, doesn't take much to get that label I guess.
Well, I think Grishnakh said everything I would have had to say down here:
http://slashdot.org/comments.pl?sid=2413768&cid=37311778 [slashdot.org]
And as with the Wright Brothers who hadn't reached the
Re: (Score:3)
Oh please. Do you even know anything about physics or the current state of battery technology?
The Wright Brothers were still trying to figure out principles of aerodynamics and invent a craft that could fly through the air in a controllable manner. (Some other people had already invented working airplanes before them; they weren't the first. The problem was that their predecessors made planes that took off, flew a short distance, and then crashed. The Wrights invented a plane that could turn.) We don't
Re: (Score:2)
If they'd have waited for suitable batteries to be developed for mobile phones, before building phones, then we wouldn't have anywhere near as good mobile phones right now.
Instead they just used the batteries that were available at the time, and accepted the fact that a mobile phone needed a battery-pack the size of a shoebox.
It was the fact that there was an actual demand for better mobile phone batteries that spurred development. That demand wouldn't have been their had phone manufacturers waited.
Same goe
Re: (Score:2)
If they'd have waited for suitable batteries to be developed for mobile phones, before building phones, then we wouldn't have anywhere near as good mobile phones right now. Instead they just used the batteries that were available at the time, and accepted the fact that a mobile phone needed a battery-pack the size of a shoebox.
Bad comparison. I'm old enough to remember the "bag phones". Back then, sure, batteries weren't quite as good, but that wasn't the biggest problem, it was the phone technology itse
Re: (Score:2)
You make a good point that shoebox powered mobile phones were still and practical useful for certain markets. Whilst ultra short flight helicopter's aren't. And yet you're comparing an early shipping product to a hobbyists first prototype.
Back then, sure, batteries weren't quite as good, but that wasn't the biggest problem, it was the phone technology itself.
Well yes. And also the fact that cell towers are a lot closer today, so lower power is needed. And yet those two don't completely explain the progress from a shoe box sized battery to today's tiny batteries.
The batteries back then were Ni-Cd. Now they're Li-ion or Li-Po. I
Re: (Score:2)
You make a good point that shoebox powered mobile phones were still and practical useful for certain markets. Whilst ultra short flight helicopter's aren't. And yet you're comparing an early shipping product to a hobbyists first prototype.
The laws of physics prevent that "prototype" from ever becoming anything useful. Is the hobbyist working on improving battery technology? No? Then it won't work. The problem isn't helicopters, it's energy storage.
Well yes. And also the fact that cell towers are a lot c
Re: (Score:2)
We ought to.call you Scotty. "Ye cannie change the laws of physics captain."
Clearly there is no such law of physics, since there already is a technology that packs the required energy density. A fuel tank. We're looking for an alternative to something that already exists, not something impossible.
Re: (Score:2)
Clearly there is no such law of physics, since there already is a technology that packs the required energy density. A fuel tank. We're looking for an alternative to something that already exists, not something impossible.
I never said batteries with the energy density of a fuel tank are impossible, only that they don't exist right now. What's impossible is using today's battery technology to create a helicopter that can come remotely close to replacing a conventional fossil-fuel-powered one. People keep s
Re: (Score:2)
The control stick setup reminded me a little of the Kolibrie helicopter [youtube.com], which has a similar "hobby" look to it. By the way, someone mentioned ba
Re: (Score:2)
I've got an analogous design of hoverboard. Around 30 kilos - so just about portable, can do nearly 2G of acceleration from a standing start, and will get you to around 3km altitude.
Of course, it costs several tens of thousand dollars, and would make a noise that would make the dead go looking for earplugs, and has a 'flight' time of 3-4 minutes.
(15Kg of really fast discharge rated li-ion, around a hundred closely packed ducted fan units, and a nutter on top)
Re: (Score:2)
It's a 'sheet of a4' design, admittedly.
However, the power budget is achievable in the mass budget, the control gear is not fundamentally harder than a quadcopter - though a lot more numerous.
All of the constituent parts are readily available, it's 'simply' a case of putting them together in simple ways.
'40C' quality li-ion cells are not hard to find, nor are reasonable thrust/weight ratio ducted fan units, nor are ESCs.
Sure there are major issues, the control laws at liftoff and transition through ground e
Re: (Score:1)
Really, the only dead end is use of batteries. I reckon more suitable fuel cells will come as soon as there's a need.
Re: (Score:3)
Aircraft are all made as light as they can possibly be and still fulfill their design function. The skin of you typical general aviation four place single engine is about twice as thick as a bear can. Airliners are very very fragile as evidenced by whats left when they crash as the pretty much just shred into little shards of aluminum and about the only parts left intact are the engine cores and landing gear.
Re: (Score:2)
Is that for an adult bear or a baby bear?
Re: (Score:2)
Yeah Yeah Yeah... I want a spell checker that can read my mind dammit! lol!
Re: (Score:2)
Re: (Score:2)
I am pretty darn sure I am going to be completely decomposed long before this ever happens
Perhaps in certified form, especially heli's, but take a look at what is happening in the experimental space.
There are a number of electric hybrid aircraft in development that are starting to look like we will see some practical applications in 2-3 years. Burt Rutan flew one to Oshkosh this summer. The biggest difference is they are not trying to carry all the energy in batteries, but rather just enough for takeoff. Charge the batteries with small highly efficient engine powered generator, and use a sim
Brilliant achievement (Score:2)
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
I'm a licensed A&P mechanic.
You service shopping carts? =)
Re: (Score:1)
Re: (Score:2)
Ah, a fellow TWI-certified Visual Inspector of Welds!
Are you wiv me?
designed and built almost entirely by himself (Score:1)
yea no shit that thing looks like its 1 good hit from falling apart, whats going to happen on a hard landing ie if your battery starts to die, some angle welded aluminum and 2 giant spinning food processor blades all going apeshit with you in the middle?
have fun buddy
Re: (Score:1)
backup power? (Score:2)
I love the part in the article about using batteries and an electric motor to land a helicopter in case the main engine dies. Here are a few issue with that;
1. High cost of batteries and a motor big enough to land the helicopter.
2. Lift capacity decrease due to the weight of batteries and electric motor.
3. The extra fuel needed to carry the weight of the batteries and electric motor causing higher flight costs and shorter range.
4. Maintenance costs on batteries and motor that will probably never be used.
Int
Re: (Score:2)
Re: (Score:1)
You forget about this
http://en.wikipedia.org/wiki/Height-velocity_diagram
Every helicopter has a portion of its envelope where a safe autorotation isn't possible.
Re: (Score:1)
1. High cost of batteries and a motor big enough to land the helicopter.
> Given the cost of a typical helicopter, Li-On batteries + electric motor on the scale that this guy used, is probably a minor incremental cost.I am thinking along the lines of Honda Civic style mild-hybrid - beefed up batteries from what is normally carried and a electric motor that adds to peak output rather than totally replace it.
2. Lift capacity decrease due to the weight of batteries and electric motor.
> True - there would
Ground effect (Score:5, Insightful)
Disappointed for Two Reasons (Score:2)
I was disappointed by this coverage for two reasons:
1. I wanted to hear it.
2. I wanted to see it rise above ground effect.
Why do we have to shit on his acheivement? (Score:2)
Fscking hell. He just built a helicopter. I say congratulations!