It is:) Last year Siemens demonstrated an electric motor for aircrafts with a power-to-weight ratio of 5000 W/Kg. The modified C172 i mentioned before used an off the shelf tri-phase motor and they had to place batteries on the front because the aircraft was all of the sudden tail heavy. On top of add, they needed ballast to keep the CG within specs.
I just wish someone came up with an usable power storage solution. Electric engines are a dream come true for aircrafts.
You're seriously underestimating how lightweight electric engines are for a given power output - it all boils down to the fact that they're mechanically very simple.
A state of the art GENx aircraft turbofan engine (as the ones powering the 787 dreamliner) has a dry weight of 12,400 lbs. A marine 10MW electric engine weights 9,000lbs, and that is with a fully enclosed, liquid cooled, waterproof casing around it. Make it air cooled (these already exists too) and you'll halve that weight.
Granted, you still need to worry about control electronics and power but, again, the actual motors were never an obstacle to have an electric airplane. IIf anything, electric engines are a great idea because they're powerful, small, lightweight and have basically zero maintenance. It is all about the power storage.
Well, i imagine you could power them using a regular gas engine. This would mean that you could (theoretically) run the petrol engine at its optimum power settings to decrease fuel consumption, but you're still left with a myriad of problems - increased mechanical complexity, loss of power with altitude, etc. I don't know if this is the intent of the project.
A "true" electric airplane would use an electric motor and batteries as a power plant. This setup would be orders of magnitude more efficient and reliable than regular petrol engines, but we're unable to figure out how to store power without adding too much weight.
I'm not an aerodynamicist, but from what i understand this would not be efficient at all: you cannot tap into induced drag without introducing other surfaces. At best, you'd be trading induced drag (vortex related) for parasite drag (related to shape, construction and materials).
From what i've read, the main issue they had was not safety but (surprise surprise) weight. It took a lot of shielding to protect the crew from the reactor's radiation.
Yeah, but to a much lesser degree. Aircraft engines are usually optimized for a given altitude range - normal piston engines decrease power with altitude. Turbochargers improved on this, but they suffer the same issue. Turbofan engines used on airliners have peak efficiency at cruise altitude but suck when flying low.
In general, air density is the main factor impacting aircraft performance, because it impacts on three separate thing: how the engine runs, how much lift can the wings generate and how much air can a propeller push or a jet can suck. Of those, the first one is by far the most important, as it in it can compensate (to a degree) for the rest.
This was actually tried in the past: both the USA and the ex-USSR experimented with nuclear powered engines. Instead of electric engines they used regular jet engines, with the combustion chamber using heat from the reactor instead of burning fuel. It worked fine, the problem was they were unable to properly shield the crew from the reactor's radiation without adding too much weight.
"Lean of peak" is common on modern piston-engine aircrafts; you trade off a little power for a significant fuel economy. John Deakin wrote a fantastic piece on the subject.
The engine is the easy part. We already have plenty options for efficient electric engines on any power range you'd like. I recall a group called "Bye Electric" fitting a C172 with a 200hp electric engine with little issues.
Power storage is everything. Every single option to store electric energy onboard an aircraft is orders of magniture less power-density efficient than gas.
I'd love a reliable, commercial electric airplane to become available. Sadly, we're very far away from that - electric engines can be made to be very efficient but you still need batteries to power them, which weight a lot. Either that, or a gas based poweplant, which beats the point entirely.
I wish someone started looking into nuclear powered jet engines again. Unlike electric this technology really did show some future.
Of course that's the official reply line, but it its hard to believe. I haven't read the WoW EULA, but i'm pretty sure running a private server is no illegal either.
Possibly, but at the same time Blizzard has a strong investment in their new AAA titles. I assume they dont expect all 800k users to switch to their new games, but they do expect a good fraction of them to do so. MMORPG players are as close as you'll get to a meth addict in the online world.
History proves that statement false; this isn't the first time they used an army of lawyers to crush private servers. Starcraft multiplayer wasn't even subscription based but they still nuked bnetd.
And users of bnetd were not using Battle.net. Same deal. Don't forget, Starcraft is still huge, specially on Asia where pro gaming Starcraft events are televised.
It its the same logic used by Hollywood to attack piracy, really. It doesn't matter if those users would never have a Blizzard account; in their eyes, there's a chance they would.
The point is exactly that those 800k were not playing on Blizzard servers.
That's all there is to it, really. They don't care about private servers for outdated games; they care about not having those users playing (and paying) on their network.
Honestly, that's to blame on Ubuntu. Most other distros handle multi-architecture packages with grace. On Arch you can just install it as a regular package and the 32-bit dependencies are installed nicely alongside whatever your system runs on.
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Can you fly a drone in VFR airspace though? Pretty much everywhere in the world that airspace is restricted to licensed aircraft.
It is :) Last year Siemens demonstrated an electric motor for aircrafts with a power-to-weight ratio of 5000 W/Kg. The modified C172 i mentioned before used an off the shelf tri-phase motor and they had to place batteries on the front because the aircraft was all of the sudden tail heavy. On top of add, they needed ballast to keep the CG within specs.
I just wish someone came up with an usable power storage solution. Electric engines are a dream come true for aircrafts.
You're seriously underestimating how lightweight electric engines are for a given power output - it all boils down to the fact that they're mechanically very simple.
A state of the art GENx aircraft turbofan engine (as the ones powering the 787 dreamliner) has a dry weight of 12,400 lbs. A marine 10MW electric engine weights 9,000lbs, and that is with a fully enclosed, liquid cooled, waterproof casing around it. Make it air cooled (these already exists too) and you'll halve that weight.
Granted, you still need to worry about control electronics and power but, again, the actual motors were never an obstacle to have an electric airplane. IIf anything, electric engines are a great idea because they're powerful, small, lightweight and have basically zero maintenance. It is all about the power storage.
Again, easily achievable. ABB sells electric motors in the 10 MW range with an efficiency of ~96%. And thats pretty much off the shelf offerings.
Well, i imagine you could power them using a regular gas engine. This would mean that you could (theoretically) run the petrol engine at its optimum power settings to decrease fuel consumption, but you're still left with a myriad of problems - increased mechanical complexity, loss of power with altitude, etc. I don't know if this is the intent of the project.
A "true" electric airplane would use an electric motor and batteries as a power plant. This setup would be orders of magnitude more efficient and reliable than regular petrol engines, but we're unable to figure out how to store power without adding too much weight.
I'm not an aerodynamicist, but from what i understand this would not be efficient at all: you cannot tap into induced drag without introducing other surfaces. At best, you'd be trading induced drag (vortex related) for parasite drag (related to shape, construction and materials).
The very best supercapacitors are in the neighbour of 20 Wh/kg. For reference, petrol is 12,300 Wh/kg.
From what i've read, the main issue they had was not safety but (surprise surprise) weight. It took a lot of shielding to protect the crew from the reactor's radiation.
Yeah, but to a much lesser degree. Aircraft engines are usually optimized for a given altitude range - normal piston engines decrease power with altitude. Turbochargers improved on this, but they suffer the same issue. Turbofan engines used on airliners have peak efficiency at cruise altitude but suck when flying low.
In general, air density is the main factor impacting aircraft performance, because it impacts on three separate thing: how the engine runs, how much lift can the wings generate and how much air can a propeller push or a jet can suck. Of those, the first one is by far the most important, as it in it can compensate (to a degree) for the rest.
This was actually tried in the past: both the USA and the ex-USSR experimented with nuclear powered engines. Instead of electric engines they used regular jet engines, with the combustion chamber using heat from the reactor instead of burning fuel. It worked fine, the problem was they were unable to properly shield the crew from the reactor's radiation without adding too much weight.
On the other hand, the efficiency of regular aircraft engines vary wildly with altitude. Electric engines don't have that issue.
"Lean of peak" is common on modern piston-engine aircrafts; you trade off a little power for a significant fuel economy. John Deakin wrote a fantastic piece on the subject.
The engine is the easy part. We already have plenty options for efficient electric engines on any power range you'd like. I recall a group called "Bye Electric" fitting a C172 with a 200hp electric engine with little issues.
Power storage is everything. Every single option to store electric energy onboard an aircraft is orders of magniture less power-density efficient than gas.
I'd love a reliable, commercial electric airplane to become available. Sadly, we're very far away from that - electric engines can be made to be very efficient but you still need batteries to power them, which weight a lot. Either that, or a gas based poweplant, which beats the point entirely.
I wish someone started looking into nuclear powered jet engines again. Unlike electric this technology really did show some future.
Well, i'm not arguing this was a smart move :D
Of course that's the official reply line, but it its hard to believe. I haven't read the WoW EULA, but i'm pretty sure running a private server is no illegal either.
Is not that simple. You're comparing an open gaming network vs a paid one.
Possibly, but at the same time Blizzard has a strong investment in their new AAA titles. I assume they dont expect all 800k users to switch to their new games, but they do expect a good fraction of them to do so. MMORPG players are as close as you'll get to a meth addict in the online world.
But of course they do. Battle.net is still up and running and owned by Blizzard.
History proves that statement false; this isn't the first time they used an army of lawyers to crush private servers. Starcraft multiplayer wasn't even subscription based but they still nuked bnetd.
And users of bnetd were not using Battle.net. Same deal. Don't forget, Starcraft is still huge, specially on Asia where pro gaming Starcraft events are televised.
It its the same logic used by Hollywood to attack piracy, really. It doesn't matter if those users would never have a Blizzard account; in their eyes, there's a chance they would.
Blizzard does not care about private servers for an old game. They care about the 800k users which are not paying to play on their network.
The point is exactly that those 800k were not playing on Blizzard servers.
That's all there is to it, really. They don't care about private servers for outdated games; they care about not having those users playing (and paying) on their network.
The only law they broke is to reduce the subscribers base for Blizzard online services. That's just cold, man.
Honestly, that's to blame on Ubuntu. Most other distros handle multi-architecture packages with grace. On Arch you can just install it as a regular package and the 32-bit dependencies are installed nicely alongside whatever your system runs on.