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First Fully Electric Manned Helicopter Flight
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.'"
Major props to this guy.
According to Wikipedia, most of the noise from a helicopter is generated by the rotors, so although I'm sure the electric engine will be quieter than turbine engines used in most helicopters today, it's not likely to make a huge difference to the overall noise.
Amazing development from such a tiny operation! However, I recommend he employ a professional welder. The one rather important-looking weld he shows in a pic looks a little dodgy.
Fuel taxes are not how the FAA is funded. You sir suck at sarcasm.
The rest of your pathetic attempt failed just as poorly.
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.
Not to belittle the achievement- but a height of 1 meter means he never got out of ground effect. It would take a lot more power to really fly. I mean, if a vehicle never goes out of ground effect while flying over water, it can be registered as a boat.
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.
Finally! A year of moderation! Ready for 2019?
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.
Hey KID! Yeah you, get the fuck off my lawn!
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 different method of generating anti-torque force). But if you've ever been near an MD500 in flight, you'd know that these helicopters aren't quiet either, just not quite as obnoxious as the traditional styles. Other helicopters with tail rotors do things such as space the tail rotor blades unevenly, or point the tail rotor off-axis, to reduce the noise signature. Take a look at the tail rotor on an Apache AH64D or a Comanche (which never got past prototype stage).
The only way you're going to make a truly quiet helicopter is to make one that doesn't have any rotors at all, and lifts itself with antigravity propulsion, which is clearly in the realm of Star Trek. Or, I suppose you could make one with really small rotor blades, like maybe 12 inches across, but then you'll be restricted to a craft that can only lift a pound or two of weight. Those R/C helicopters everyone's selling these days are fairly quiet, but don't expect to carry much with one.
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 is a replacement for a normal car.
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 have that problem; we already know how to make high-performance airframes. We even know how to make high-performance electric motors that could power them. The only thing we don't know is how to store enough energy in a small enough and light enough device to make an electric aircraft a viable alternative to current fossil-fuel powered ones. Building prototypes isn't going to change that simple fact.
If you want to make electric aviation a reality, you have to wait for the people working on battery technology, or start working on battery technology yourself. Battery technology is a very different domain from aerospace engineering, but putting people to work building unusable electric aircraft isn't going to move battery technology along any faster than it would help GPS navigation technology; even though most modern aircraft use that too, it's not something aircraft builders have any expertise in, they just buy a Garmin box and bolt it into the cockpit.
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 found something that worked and provided the required energy density. Aviation isn't the only place where batteries with much higher energy densities would be very useful; everyone's screaming for electric cars these days (which burn far, far more fuel than aircraft in total), and those aren't quite viable yet either, because of battery technology. Plus, everyone wants their phone or their laptop to run longer between charges. Aviation is probably going to be the last place to move away from fossil fuel, because the energy density is such an important requirement, far more so than in ground vehicles.
This guy accomplished something very few people will ever achieve and yet half the posts above are "what's the point", "shitty welds", "batteries suck", etc.
Fscking hell. He just built a helicopter. I say congratulations!
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