Originally Posted by
gevans35
I think so too, powered by a generator run off the main engine(s).
Actually, why not the main rotor too? They do it in ships so why not aircraft?
Would take a lot of development though...... Elon Musk?
I thought this was just a joke/trolling, but since it seems that some of you are serious:
I can see only one thing that speaks for an electric TR and that is that you wouldn't need pitch controlled blades. I'll mention a few things that come to mind that speaks against it, although I'm sure there are many more:
- I'm sure there's a lot of computer control in most modern helicopters already, but this would have to be entirely computer controlled to be at all flyable. That would open up a new can of worms when it comes to safety. I know that "fly-by-wire" is popular these days, but personally I only consider it "safe" as long as everybody is equipped with ejection seats.
- The reason they use electric motors on ships is first and foremost because it's difficult to get the mechanical energy to where you want it. Imagine the arrangement of driveshafts and gears that would be needed to transfer the power from the engine(s) to multiple azimuth thrusters placed on different locations, some probably near the bow. On trains they often do the same, but from what I understand that's for similar reasons (you want drive on as many wheels as possible because trains generally have bad traction) and because making gearboxes that can take the punishment over time is difficult. However you twist it, converting mechanical energy into electrical energy and then back again means that you'll both have a lot of extra potential points of failure and waste a significant part of the energy. Driveshafts and gearboxes waste energy too (through friction in bearings etc.), but considering how simple (geometrically) this is on a helicopter I'm convinced that using driveshafts and gearboxes is much more efficient.
- There's nothing inherently "environmental friendly" about electrical motors. It all depends on what form the energy is available in to start with. If you use a combustion engine to turn fuel into energy, you have mechanical energy as the source. What is considered "environmental unfriendly" is the combustion engine itself, converting the energy to electricity after the engine makes no sense (although some cars do this to ride the hype). If you have electricity as the power source using for example a battery or fuel cells, things are very different.
- As mentioned above, the only "gain" by using an electrical TR that I can see it that you wouldn't need pitch controlled blades. That said, changing the pitch is very quick and doesn't take a lot of power. The RPM is already there, ready to be used. A fixed pitch blade rotor would have to vary the RPM instead, and I believe this would be much too slow to be practical due to the inertia in the rotor. I guess that if you could make it by some revolutionary new hyped nano-materials that's stronger than steel but weighs nothing, the inertia problem could be overcome. I don't know of any such materials outside the world of hype though.
In addition I'd just like to mention that I believe Elon Musk's strongest asset is his ability to create hype and "impress people" enough to invest in him. I think time will reveal a different picture of him, and I certainly wouldn't like to fly anything designed or built by him or anyone like him.