Electric R22 anyone?
Just thinking out of the box...
If you take a Robinson R22 and remove the Lycoming engine, battery, alternator, drive shafts, clutch, belts, and both gearboxes, fuel tanks, how much does the unpowered fuselage weigh?
Now, if you replace all of those components with a pair of DC electric motors - a big one driving the main rotor and a little one in the tail - control equipment and as many Lithium-Ion batteries as you could carry up to the same weight, how much endurance would the resulting eco-friendly machine have?
I'm not an engineer, and I don't have ready access to the numbers, but I know that:
- Electric motors are a lot lighter than piston engines
- Electric motors are way more efficient
- Startup, shutdown and carb icing wouldn't be problems any more
- There would be a lot less moving parts, and reliability would be increased
- The end result would be eco-friendly and very cheap to run!
However...
- Avgas has *much* higher energy density than, say, lithium-ion batteries
(this is probably the showstopper - figures, anyone?)
- Power and control systems would be critical to safe flight
If we get the weight & balance right, who's up for a ride in the result??
Benet