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Quadropropellor concept Answered

Last night I had this dream about a bizarre helicopter that used a simple but unique form of a propeller.  Conceptually, I see no reason why it should not work... but I'm not sure if it would be any better or more efficient than a typical propeller.  The idea is that the geared propellers rotate at the tips of the main rotor as it spins.  The outside ring is fixed such that as the central propeller spins, each of the out side disc spin creating lift from both the central propeller as well as each of the four outside propellers.  Because the geared wheels will spin faster than the central rotor, theoretically it might produce more lift than a single propeller (maybe).  I would like to hear other people's thoughts on the concept.  If someone has a 3D printer, it should be relatively simple to make and test.


I might be wrong (don't own or ever flew a multi copter), but AFAIK, all quad/hex/octo-copters have half their propellers run clockwise and the other half counter clockwise to cancel out the angular momentum. Not sure how your idea would behave, but I guess that there is no proper momentum cancelling. Furthermore, Traditional multi copters can be turned in the air by having one set of rotors (e.g. the clockwise turning ones) run faster/slower than the other set. With your design all rotors have the same speed. So you can't create angular momentum and probably not steer the copter at all. For efficiency, I'm all with Kiteman.

The design is not for a true quadro-copter in which the propellers lift and steer the copter by the use of four separate propellers. It is instead a re-design for a single propeller. So, for a quadro-copter, imagine four of these with this replacing each traditional propeller. I picked the name quadropropellor because of its four internal propellers.

Okay, if it is for a standard helicopter (one main rotor and a tail rotor to stop spinning) then it's a total different story. And won't work at all.

That's because the rotor of a helicopter is not only a fixed spinning propeller to create uplift. The blades of the rotor are tilt-able and tilted differently while going forward and backward (as seen in flight direction) to create lift and drag into the direction wanted.

Check this videos for information how choppers work.

I can't see how this generates any more lift than a standard propeller - I think 3/4 of the smaller blades will either be in line with the movement, or moving backwards relative to the air.

With the extra friction and weight involved, I think it will actually be less efficient than a normal propeller.

However, I think it looks very cool, and I'd love to see it running for real, just for the fun of it!

@Kiteman Yes... that is what I suspect... that the extra friction and weight might offset any power gained by the gear ratio of the rapidly spinning internal propellers... but I'm not sure with the light weight and precise plastics that can be made these days. I do think it would look incredibly cool. :)

I'd like to see it made real, purely for coolness' sake.