Latest attempt at getting airborne on battery power.

What exactly is the advantage of one of these machines over an electric Mosquito helicopter which has a payload of 85kg, hover endurnce of 20 minutes, and most importantly can autorotate?
What is the weight of the electric drive arrangement vs the internal-combustion driven rig? I'm interested in the possibility, not of pure electric helos, but of using electric power transmission. Still, this would give me an idea.
 
Electric flying machines are entirely practical; all that’s required is a long, heavy duty extension cord.
For contemplating operation on storage batteries, it would be a good idea to compare the amount of energy stored in a pound of gasoline vs a pound of storage battery and then looking at the energy requirement of a rotary wing flying machine.
Old Issac Newton with his conservation of energy laws was a real spoilsport for us fantasizers.
Yeah. Depending on what assumptions you make, there is a twenty- to forty-to-one advantage for liquid fuels. That would suggest either electric power transmission or a true hybrid as the short-term solution. Electric transmission would emancipate us from the weird and wonderful mechanical transmission mechanisms that you see in light helicopter plans.
 
Comparing energy content of a pound of gasoline to a pound of batteries doesn't account for the radically better conversion efficiency of an electric motor over an internal combustion engine (which makes substantial amounts of useless heat). The weight advantage is clearly still with fuel, but not by as much as the proposed comparison alone might suggest.
 
Energy conversion from batteries to thrust is about 3x better than gas, if we use 30 x energy storage advantage for gas we have roughly 10 times better power to weight advantage for fuel. It might be more like 8-9 since electric motors weigh less for equivalent output. At. This. Time.
 
Could you make an entirely self contained rotor for a heli that had tip propellors (like tip jets) with its own pitch regulators and vanes for directional control and just have the batteries replace the engine and transmission of a normal s.all heli?
Sure it might have ginormous ugly rotor system, but I'm imagining something like a Kiowa with a radome....which is ugly too.
 
What is the weight of the electric drive arrangement vs the internal-combustion driven rig? I'm interested in the possibility, not of pure electric helos, but of using electric power transmission. Still, this would give me an idea.
The motor was 12kg and the drive 8kg. Add a water pump and total drive weight was about 22kg compared to 39kg for the MZ202 motor.

But that is not where the story ends. The MZ202 runs at 6000rpm and needs a primary reduction down to 2500 rpm for the tail rotor drive. The electric motor runs at 2500rpm, so already we can get rid of the primary reduction.

When changing from a mechanical tail rotor to an electric tail rotor things get even more interesting. The electric tail rotor (including battery) weighs less than the mechanical tail rotor, but more important is the freedom an electric tail opens to how the main rotor drive motor can be mounted.

In the end a lot has to do with the design freedom that opens up when moving to electric power. A complex mechanical system with multiple reductions, multiple drive shafts and a clutch can be replaced by a very simple mechanical system with potentially one reduction, no drive shafts and no clutch.
 
Another concept under study.

 
Wings, rotors, parachutes, props -- and other gadgets that obtain thrust by shoving air about -- are all bound by the rules that govern action-reaction schemes. It takes less power (=energy consumed per second) to accelerate a LOT of air a LITTLE than to accelerate a LITTLE air a LOT. This rule steers us toward low disk loading for low-powered devices. IOW, large-diameter, slow rotors use power more efficiently.

All "backpack" lifting machines suffer under this analysis. The Bell Rocket Belt is perhaps the very worst; its disk area is the diameter of its rocket nozzles (yes, they shoot steam, not air, but the same rules apply). The Bell Jet Belt is a tad better, in that its exhaust nozzles are bigger.

This twin-rotor backpack is better still, but nevertheless has a disk area far too small to be even reasonably efficient. It's gonna be one serious power hog -- the last thing you need, given the power-to-weight ratio of electrics.

The 1950's helo backpacks had bigger rotors and did better in the disk-loading department.

Interestingly, Igor Bensen built an uber- crude direct-lift aircraft that was essentially a sawhorse with a vertically-mounted McCulloch engine and prop on each end. Igor straddled the sawhorse between the two engines.. It got off the ground -- but it sure ought to, with two 72-horse engines lifting one guy. How many pounds of batteries is that?
 
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For the last two weeks, I've been driving a 2010 all-electric Nisan Leaf. This was the first year they made them with a range of 40 miles. = In the day without the lights or heater on range. It cost me almost nothing so far as I have a solar system on the house and pay almost nothing for the electric bill including charging the car. All clients and friends have had a way for me to plug in and charge.

When I saw Leigh's post and read the 53-mile range = without the heater on distance.
From my new actual experience driving electric Leaf, I know how I would really use such a short-range aircraft.
Assuming there was a place to land at restaurants, grocery stores, downtown San Diego & back and the airport hangar and back.
But only the airport has a place to land and park an aircraft and I can only recharge at my hangar.
I can drive it to the medical center but have to recharge to drive back home. The good news is they have 2 ChargePoint quick chargers in the parking lot recharging in the hour I'm at the appointment and it only cost me $1.98 to get back home. Compared to $4.95 in my car.

There are no stoplights for traffic in the sky. Who is going to control the thousands of flights and their landing = big brother?
Else can you imaging fighting over charging landing pads when your almost out of electricity.

I cannot use it to fly to my instructor and back need my car or better my gyro or FW for airport to airport.
I'm surprised at how much I do use the Leaf... and I've never driven slower in my life trying to squeeze the last mile out of her at the max ranges.
I'm enjoying driving the actual speed limit too until I'm not behind another slowpoke and I'm the one holding up traffic in the right lane. Then I'm not laughing at the slow speed and I punch it to catch up with the next slow truck so they blame him not me.
If I keep using it like this thinking of getting a Tesla and driving my normal speeds too. It could drive to my instructor and back without recharging.

I like the idea of flying cars but it would require traffic control, landing, and parking infrastructure at every store, or we are still all walking or paying for Uber from mini airport to mini airport.
 
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PS: I would not fly them to Catalina Island even with a ballistic chute. HahahahahahahHehehehehehehe
 
Of course, heavier-than-air aircraft use a goodly portion of their energy just holding themselves off the ground. Cars don't have this need.

It's not actually NECESSARY to use up any energy at all to hold yourself off the ground. A helium/hydrogen balloon uses zero energy to stay up, just as the car does. Aerodynamic devices OTOH shove air around (heating it up). Warrm and turbulent air, in itself, does us no good. But then we employ a BYPRODUCT of this shoving-and-heating process (the reaction) to hold ourselves up. This looks -- and is -- wasteful in a way, but birds, bats, and bugs have made a "go" of it for millions of years.

Still, lighter-than-air craft are the most energy-economical flying machines. Trouble is, they're BIG, and not very agile.

And incendiary, if you use hydrogen.
 
Of course, heavier-than-air aircraft use a goodly portion of their energy just holding themselves off the ground. Cars don't have this need.

It's not actually NECESSARY to use up any energy at all to hold yourself off the ground. A helium/hydrogen balloon uses zero energy to stay up, just as the car does. Aerodynamic devices OTOH shove air around (heating it up). Warrm and turbulent air, in itself, does us no good. But then we employ a BYPRODUCT of this shoving-and-heating process (the reaction) to hold ourselves up. This looks -- and is -- wasteful in a way, but birds, bats, and bugs have made a "go" of it for millions of years.

Still, lighter-than-air craft are the most energy-economical flying machines. Trouble is, they're BIG, and not very agile.

And incendiary, if you use hydrogen.
Funny I was just watching an old Richard Feynman lecture last night and the way you describe things kinda reminded me of him. He was very good at explaining physics in meaningful ways.
 
Of course, heavier-than-air aircraft use a goodly portion of their energy just holding themselves off the ground. Cars don't have this need.

It's not actually NECESSARY to use up any energy at all to hold yourself off the ground. A helium/hydrogen balloon uses zero energy to stay up, just as the car does. Aerodynamic devices OTOH shove air around (heating it up). Warrm and turbulent air, in itself, does us no good. But then we employ a BYPRODUCT of this shoving-and-heating process (the reaction) to hold ourselves up. This looks -- and is -- wasteful in a way, but birds, bats, and bugs have made a "go" of it for millions of years.

Still, lighter-than-air craft are the most energy-economical flying machines. Trouble is, they're BIG, and not very agile.

And incendiary, if you use hydrogen.
but birds, bats, and bugs have made a "go" of it for millions of years,
and human glider pilots have made a go of it for the last 100 years or more too.
 
Hooray! I finally managed to get airborne for 90 seconds on battery power alone!
Oh, wait a minute; what’s it good for other than chest thumping?
 
Hooray! I finally managed to get airborne for 90 seconds on battery power alone!
Oh, wait a minute; what’s it good for other than chest thumping?
Yes, you are correct. But what if you understand how to use physic to create a permanent magnet motor that would run for 100 years before it lost its magnetism. Don't laugh. In the 5th grade, I entered one in our science fair after my science club teacher said physics says it impossible. I told him I knew how and would bring it tomorrow and set it on his desk. Made it out of an elector set A-frame with an axle through an oak meal round box top. It was a ferrous wheel of magnets with an opposing larger magnet on a thread wood spool. Set it on his desk with the attractive poll in front of it to get it started spinning and then spun the spool around to opposing polls and it kept spinning. I left his 6th-grade class and went back to my 5th-grade class and said "NOTHING".
At first recess, I opened his door looked at it, and said. "Looks like it is still spinning to me!" And shut his door. At lunch, I said "Hey Mr. Fox appears physic, and the science community is WRONG as it looks perpetual to me.
The next recess he told me to come in before my next well-thought-out smart-ass comment!
After more than 60 years of telling others how you could make a 3 turbine with 10 cylinders each permanent magnet motor, I'm going to make it myself. Chuck's brother makes customized handicap vehicle controls in his machine shop.
Here is how you can make one. I'm been too busy living life to the fullest but running out of life, need to do this before I die.
Just in case here is how you could build your own...

In the 5th grade, I realized that all disks have only one 90 degrees timing point. That is exactly like an armature of an AC motor.
For a permanent magnet motor, you time the attractive side but not to its at-rest state at 90 degrees like you do with opposing coils and magnets in AC motors. I'm timing these cylinders at 33 degrees offset. They are always trying to get back to 90 and at rest but can't because of timing gears.
The other property of a disk I realize is the magnet field changes direction away from each opposing cylinder allowing the other difference from an AC motor. You create a slight dwell that is a gap in the magnetic fields. That is done by spacing the alternating rows of magnets on each turbine to the position where the next row is on the opposing cylinder attracting it by a 33 degree offset.
Any 5th grader who studied electricity and electromagnets, like I did, at the library and did not know science said it's impossible could make one.
 
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