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Electric motors for aircrafts

  1. Nov 29, 2013 #1
    Greetings, everyone!

    A couple of my friends and i started work on a project regarding VTOL aircraft design. We are interested in the concept of propelling the air vehicle via propellers rotated by electric motors. As all of us, have relatively limited knowledge on electrical components/systems i hope some of you will be able to give me some guidance on a few electric motors used in some lightweight/aerobatic aircrafts. We are intending to dig up in this field and try to come up with a design with solar panels and probably using a car engine ( as a hybrid ) for charging batteries.

    Our idea came for the so called ,,Project Zero'' of Agustawestland company. I am pretty much aware that electric powered aircraft are still far, far behind in their development when compared to gas turbines. The reason pretty much lies in the battery technology which needs to be boosted further.

    Still, i believe that if we come up with a decent suggestion for propelling the machine, at least making our idea clear and stating future conditions which can make it possible we are likely to do well. This is the reason why our group did go straight at the beginning for a turboshaft/turboprop.

    Thank you in advance, for any comments!

    Really, hope someone will drop lines!
  2. jcsd
  3. Nov 29, 2013 #2

    Simon Bridge

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    Welcome to PF;
    Was there a question in all that?

    You should continue to look at how other people have been solving these problems - lightweight aircraft using electric motors are commonplace and cheap. Then, you'll be able to obtain some parameters and get an idea how they scale.

    As it stands, your project is far too open to allow much useful advice.

    iirc some hobbyists have even managed to make electric 'copters capable of lifting a man - following the quad-copter style of design.
  4. Nov 29, 2013 #3
    One thing about hybrid and electric cars is that they use regenerative braking. That means that when you press the brake the motor becomes a generator and recharges the battery while slowing the car at the same time. You can get some really good gas/charge mileage that way.

    Another thing to consider is that planes are much more efficient than VTOL's. Even the smallest autogyros pack about 100 horsepower so that they can fly. That's about 75 kW!

    Every pound is going to count and you mentioned a hybrid style engine. It's going to be heavier than a purely electric or gas motor and that will cut down on your flight time.

    Electric powered ultralights are becoming popular. We had an airshow where I work and I saw many of them. The coolest thing about them to me was that they were so quiet. Also, if they run out of charge they can still glide to a landing.

    I'm sorry to be so critical. It's an interesting idea. I hope you can make it work. I think a good place to start would be looking at electric ultralights. I'm sure their engines were picked to be light-weight and efficient.
  5. Nov 30, 2013 #4


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    There was a recent successful flight of a human powered helicopter, winning the $250,000 Sikorsky prize.
    So it is possible to do VTOL with less than a horsepower. It is just that the winning design is impractical for normal use.
    To build a practical unit requires ruthless design priorities, starting with the payload, which sizes the design.
    To allocate payload on solar panels and chargers is an unaffordable luxury for a first model. Ditto auxiliary power plants. If the design is to be electric, use batteries. Using a combustion engine to drive a generator to drive an electric motor just adds weight and cost. Stay focused on your goal, electric VTOL flight. Anything else is a distraction that simply wastes time and money.
  6. Dec 1, 2013 #5


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    Google for energy density, that's a term you will need to be familiar with.
  7. Dec 1, 2013 #6
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