Thread: Magnetic motor for airplane

I had a thought of building an airplane and was thinking of using magnetic force to spin the propeller blades. I have thought of about two ways of making them spin, 1 being place magnets around the drive shaft and having another set of magnets and have their poles be N and N facing each other to make it spin. I would like to think that somewhere there are magnets strong enough to do that, so I have come here to ask if those exist, but now my second theory, I'm not even sure it could work seeing as I am inexperienced in magnetic force and how it acts. 2. Is to have a magnetic force generated by electricity around my solid magnets and therefore making it spin but I have no clue as to what the 2nd option will do I would think that I would need a massive amount of electricity to make a magnetic field that would be powerful enough to provide liftoff of an airplane. But if this is doable then why wouldn't people have already done it I think to myself, people are probably doing it and I just haven't heard about it. Thank you

What you are describing is called an "electric motor." It is not practical for propelling an airplane because the storage battery would be too heavy.

Originally Posted by Harold14370

What you are describing is called an "electric motor." It is not practical for propelling an airplane because the storage battery would be too heavy.

Precisely

Wow that was fast thank you, all for your input so in conclusion the engine would not be able to produce enough power without a massive amount of power perhaps a generator on board?

I mainly know of these items ie. electric motor and generator but have no knowledge of the output of electric units they produce on a scale in my mind.

Originally Posted by DrRocket

Originally Posted by Harold14370

What you are describing is called an "electric motor." It is not practical for propelling an airplane because the storage battery would be too heavy.

Precisely

Not necessarily. You could use Superconducting Magnetic Energy Storage (SMES). Such devices have a huge energy storage density.

I'm not sure I'd want to be sitting next to a tank of liquid nitrogen and 10000 feet, but that may just be me.

Originally Posted by Mikasauras

Wow that was fast thank you, all for your input so in conclusion the engine would not be able to produce enough power without a massive amount of power perhaps a generator on board?

A generator wouldn't be much use in that situation. A generator changes mechanical energy into electrical energy. You want to end up with mechanical energy to turn the propellers.

Maybe you could build something like this

http://www.youtube.com/watch?v=z8qvS...eature=related


(even if it wouldn,t be an over-unity device it still could have a high enough rendition as an electric motor and as it seems to have an electron flow from the outside to the inside it could also be made working on a battery I suppose.

Originally Posted by Waveman28

Not necessarily. You could use Superconducting Magnetic Energy Storage (SMES). Such devices have a huge energy storage density.

So far as I know, these are very, very heavy. Their energy density is very good in terms of energy/volume, but the energy/mass ratio is terrible. They are usually used on the ground, where no one cares how much they weigh because you never have to move them.

Originally Posted by Harold14370

Originally Posted by Mikasauras

Wow that was fast thank you, all for your input so in conclusion the engine would not be able to produce enough power without a massive amount of power perhaps a generator on board?

A generator wouldn't be much use in that situation. A generator changes mechanical energy into electrical energy. You want to end up with mechanical energy to turn the propellers.

That is the system used in some railroad engines (diesel electric), a motor-generator set. They produce lots of torque, but don't fly very well.

I probably should have stated as to what size this craft would be, wouldn't be very large. 450-500 Lbs. The video linked by Ghrasp seems very interesting but would it be effective at moving such a large object. without consuming lots of power which would then lead to the same problem of energy:weight ratio. Could I take the same idea as to how a car is powered and use an alternator/battery combo to power this S.E.G.?

Originally Posted by Mikasauras

I probably should have stated as to what size this craft would be, wouldn't be very large. 450-500 Lbs. The video linked by Ghrasp seems very interesting but would it be effective at moving such a large object. without consuming lots of power which would then lead to the same problem of energy:weight ratio. Could I take the same idea as to how a car is powered and use an alternator/battery combo to power this S.E.G.?

A car uses the gas or diesel motor as the prime mover. That is not particularly efficient and cars are not nearly as weight-sensitive as aircraft. Your idea is inherently heavy.

For an aircraft you need favorable thrust/drag and lift/weight ratios, that puts a premium on minimizing weight.

You can safely ignore Ghrasp if you are serious. His next accurate and germane post will be his first. Brushless DC motors have many applications, including in the aerospace industry. Propulsion is not one of those applications.

Could I make the airplane out of Nylon not just Nylon obviously I would have to make a frame to put it around, but problems with strength and mounting my wings and landing gear any suggestions? It would seem as if this will be nearly impossible.

Most personal aircraft that I know of are made from cloth stretched over a frame; however, I don't know what kind of cloth they use.

You can safely ignore Ghrasp if you are serious.

You sure can and if you're not too serious you better ignore "the man who named himself after the first appollo flight he saw when he was ten years old and decided in admiration to go study fysics and then got boring real quick being a teacher" (just a guess).

My post was just a sidenote as you,re post (topicstarter) made me think of the seg because of the first idea with the magnets poled different (which won,t work by the way as you describe it). I just happen to like the seg if alone the sound of it intrigues me. Making it isn,t that easy as there has to be done some magnetizing of the core with special technicque. Also the phase of the magnetized print and the diameter of the cores and rollers etc has to be all tuned in it,s dimensions for which Searl uses a special type of math (magic squares).

Some (rocket for sure) believe it is a complete scam though and searl a lunitic which he undoubtedly is. But I can,t imagine scammers to make it so difficult (scammers always seek an easy way). And -relative - lunitics can be genius sometimes, normal people never. Tesla was also ridiculed by many.
I just love the sound maybe because I had an education as a mechanical engineer.

Originally Posted by Ghrasp

You can safely ignore Ghrasp if you are serious.

You sure can and if you're not too serious you better ignore "the man who named himself after the first appollo flight he saw when he was ten years old and decided in admiration to go studyA.fysicsand then got boring real quick being a teacher" (just a guess).

My post was just a sidenote as you,re post (topicstarter Mikasauras) made me think of the seg because of the first idea with the magnets poled different (which won,t work by the way as you describe it). I just happen to like the seg if alone the sound of it intrigues me. Making it isn,t that easy as there has to be done some magnetizing of the core with special technicque. Also the phase of the magnetized print and the diameter of the cores and rollers etc has to be all tuned in it,s dimensions for which Searl uses a special type of math (magic squares).

Some (rocket for sure) believe it is a complete scam though and searl a lunitic which he undoubtedly is. But I can,t imagine scammers to make it so difficult (scammers always seek an easy way). And -relative - lunitics can be genius sometimes, normal people never. Tesla was also ridiculed by many.
I just love the sound maybe because I had an education as a mechanical engineer.

The S.E.G would probably be great but I think what DrRocket meant when he said "You can safely ignore Ghrasp if you are serious." was that the S.E.G be too difficult for us non-Apollo named fools to fathom creating because we cannot harness these so called "magic squares".

But would could be more important then magic squares, why grammar of course ,Ghrasp stop making sentences that are illegible. it doesn't matter where you went to school because if you cant make complete sentences how will other Apollo Brainmasters as I call them, (not including me because DrRocket and I are dumb not being named after a space program and all) be able to understand what you write, it just makes you look like a boob no matter what your talking about.

You seem like a smart guy seeing as how your screenname is supposedly named about something related to space and exploration ooooh, but no matter what you're name maybe you still don't have to be a jerk on the internet at least be a jerk to your family so we aren't bothered by you.

I also have a question for Mr. Apollo about what I've quoted from you, o'great Ghrasp, I've been fascinated about this "Fysics" as you call them, PLEASE ELABORATE o'mighty Apollo Brainmaster, Please bless me with your almighty wisdom Praise be Apollo Brainmaster.

Originally Posted by Mikasauras

The S.E.G would probably be great but I think what DrRocket meant when he said "You can safely ignore Ghrasp if you are serious." was that the S.E.G be too difficult for us non-Apollo named fools to fathom creating because we cannot harness these so called "magic squares".

Not quite. I meant that Ghrasp is a fool and his posts consistently demonstrate complete lack of understanding of basic science and the problem at hand to the detriment of those who posed questions in the first place. This case is no exception.

Mr rocket (and moderators ?) you're making a fool of yourself as I was just giving the link while I thought the starter of this topic might be interested because of his first idea using only solid magnets. I was not at all planning to start a whole sub-discussion about it here and steal the topic away from the one who started it.

The way you react leads to this.

You,re being hostile in a stupid way because you can,t expect topic starter and or other readers of a specific topic like this to have read or be willing to read other topics. To get an idea they would have to do that so you,re either assuming they do or asking they do it. How presumptious can you get.

You may have "an orderly mind" I don,t doubt that but mixing topics like this is making a chaos of a forum for incidental visitors.
It shows the chaos underneath that superfluous order just fine as I don,t think you even are aware of that you,re asking and assuming this.

Also you are being rude ánd coward ( not just to me). Rude not because of the content of the words but because they are on person and therefor automatically off-topic. The rudenesss lies in that it,s almost impossible to react for someone without getting off-topic as well. So someone can't defend himself without being just as foolish as you.

The cowardness lies in that in real live you risk to get fysically hurt. If you insult people like you do on a forum you do it without such risk. Only a coward would not understand the difference.

Sorry for beïng off-topic and for my primitive English).

Originally Posted by Mikasauras

Could I make the airplane out of Nylon not just Nylon obviously I would have to make a frame to put it around, but problems with strength and mounting my wings and landing gear any suggestions? It would seem as if this will be nearly impossible.

Why nylon ? Nylon is not a particularly good material for that application. Its strength and elongation are very sensitive to moisture, it is not very stiff and not terribly strong either.

High performance aircraft can be and have been made from graphite/epoxy composite materials, which are very strong, stiff and light. An all-around better choice. Use of composites gives a robust and light airframe.

However, even with this technology you still need propulsion -- an engine. An electric motor with the attendant power supply is still not a good choice and will be too heavy.

There are electric rocket propulsion technologies, but they are not suitable for aircraft. They are used for space applications in whch gravity is not a factor (orbit keeping and deep space). The problem is that they are very efficient in terms of thrust per pound of working material (often hydrogen) but are very inefficient in terms of energy and are very low in thrust (at most several ounces). Such technologies include arc jets and ion engines.

Originally Posted by DrRocket

Originally Posted by Mikasauras

Could I make the airplane out of Nylon not just Nylon obviously I would have to make a frame to put it around, but problems with strength and mounting my wings and landing gear any suggestions? It would seem as if this will be nearly impossible.

Why nylon ? Nylon is not a particularly good material for that application. Its strength and elongation are very sensitive to moisture, it is not very stiff and not terribly strong either.

High performance aircraft can be and have been made from graphite/epoxy composite materials, which are very strong, stiff and light. An all-around better choice. Use of composites gives a robust and light airframe.

However, even with this technology you still need propulsion -- an engine. An electric motor with the attendant power supply is still not a good choice and will be too heavy.

There are electric rocket propulsion technologies, but they are not suitable for aircraft. They are used for space applications in whch gravity is not a factor (orbit keeping and deep space). The problem is that they are very efficient in terms of thrust per pound of working material (often hydrogen) but are very inefficient in terms of energy and are very low in thrust (at most several ounces). Such technologies include arc jets and ion engines.

Well then, I am officially done trying to make this airplane run off of pathetic electric power. Boats are better anyway :wink: and that should probably work on electric power too I'd also have a use for it seeing as how I enjoy fishing. And I'm not making a speed boat so I won't need any massive propulsion system. Thank you all for your help.

Originally Posted by Mikasauras

Originally Posted by DrRocket

Originally Posted by Mikasauras

Could I make the airplane out of Nylon not just Nylon obviously I would have to make a frame to put it around, but problems with strength and mounting my wings and landing gear any suggestions? It would seem as if this will be nearly impossible.

Why nylon ? Nylon is not a particularly good material for that application. Its strength and elongation are very sensitive to moisture, it is not very stiff and not terribly strong either.

High performance aircraft can be and have been made from graphite/epoxy composite materials, which are very strong, stiff and light. An all-around better choice. Use of composites gives a robust and light airframe.

However, even with this technology you still need propulsion -- an engine. An electric motor with the attendant power supply is still not a good choice and will be too heavy.

There are electric rocket propulsion technologies, but they are not suitable for aircraft. They are used for space applications in whch gravity is not a factor (orbit keeping and deep space). The problem is that they are very efficient in terms of thrust per pound of working material (often hydrogen) but are very inefficient in terms of energy and are very low in thrust (at most several ounces). Such technologies include arc jets and ion engines.

Well then, I am officially done trying to make this airplane run off of pathetic electric power. Boats are better anyway :wink: and that should probably work on electric power too I'd also have a use for it seeing as how I enjoy fishing. And I'm not making a speed boat so I won't need any massive propulsion system. Thank you all for your help.

You can buy electric motors for boats off the shelf. They are in common use for trolling motors and moving slowly around obstacles. Almost any "bass boat" will have at least one. See a Bass Pro or Cabela's catalog or look at their web site. They operate off of deep cycle marine batteries, charged by the gasoline engine on board.

there are people developing electric aircraft - I have yet to see a prototype - NASA have made solar powered ones but they are still crude in many ways.

I'm still a fan of onboard electric generation - in cars for example you can easily double your mpg and is good on things like engine wear as the generator will run in a more predictable environment.

However - the Internal Combustion Engine and generator alone will weigh alot - then you have the motor to drive the propellor (these can be VERY heavy!) and then the fuel.

Even if you half the fuel consumption on a 100 litre (fuel) capacity plane you are only saving around 50 kg of fuel - a 100 hp electric motor can easily weigh 300+ kg whereas an aluminium internal combustion engine can only weigh 100kg + fuel = if these figures are correct you can easily see why it hasn't been done.