Contraelectric

Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by Jstorrshall, Oct 13, 2018.

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  1. Oct 13, 2018 #1

    Jstorrshall

    Jstorrshall

    Jstorrshall

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  2. Oct 13, 2018 #2

    Cy V

    Cy V

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    No, I haven't seen that before. Very interesting.
     
  3. Oct 14, 2018 #3

    blane.c

    blane.c

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    nope, interesting.
     
  4. Oct 14, 2018 #4

    lr27

    lr27

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    They've had this in the model airplane world for a while.

    At this point, props and motors are the easy part. Batteries are still the hard part.
     
  5. Oct 14, 2018 #5

    Sockmonkey

    Sockmonkey

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    It is clever to make it compatible with being retrofitted on an existing plane.
     
  6. Oct 18, 2018 #6

    Andy_RR

    Andy_RR

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    ...except that going electric pretty much demands that you use every aero trick in the book to minimize drag to achieve reasonable range. Retrofitting existing airframes seems to me to be the realm of experimentation only.
     
  7. Oct 18, 2018 #7

    lr27

    lr27

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    Unless you start with an airframe that's already made to be really efficient, like a sailplane. And batteries continue to improve.
     
  8. Oct 18, 2018 #8

    pictsidhe

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    But sailplanes don't have engines to replace...
     
  9. Oct 18, 2018 #9

    lr27

    lr27

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    Ok, then use a lowly motorglider.
     
  10. Oct 18, 2018 #10

    Sockmonkey

    Sockmonkey

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    True, but creating a new production line aircraft is financially risky, so making it retrofittable to existing ones is a way to get the tech out there.
     
  11. Oct 19, 2018 #11

    leifarm

    leifarm

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    Retrofitting FES (folding propeller in the nose) is possible on pure sailplanes as long as the weight of non lifting parts is not exceeded. Many sailplanes have retractable engines for self launch or to avoid outlandings.
     
  12. Oct 19, 2018 #12

    BJC

    BJC

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    I heard that a bright, young, aero engineer in the Netherlands is developing an electric launch package that will be retrofittable to several popular sailplanes. Reportedly, it places batteries in some of the wing space originally used for water ballast and places an electric motor in the nose, which will be modified to slide forward to allow a folded propeller to extend. To save weight, no controller is used; in-cockpit switching will allow either 50 percent power or 100 percent.

    What I haven’t yet discovered is the projected first flight date, but I eagerly await the event.


    BJC
     
  13. Oct 19, 2018 #13

    pictsidhe

    pictsidhe

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    A controller will allow use of a brushless motor. The added efficiency of a brushless motor means less batteries needed. A no controller solution won't save weight...
     
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  14. Oct 19, 2018 #14

    henryk

    henryk

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    -we have some positive results with conterrotating propellers=

    =1 kW electric with 15 kG thrust, 1.3 m propellers...

    =circa 70 HP (5000 RPM) G13 , 215 kG thrust force, 1.7 m LUGAPROPs...

    (prototype gear,circa 2 kg,0.5 l volume)=low noise,focused,streamline powerfull
    afterpropeller flow=no possibility stay on futh 5 m rear!

    PS=aspatially interesting is REACTIONLESS ,
    GEARless conterrotating system ...(electro)
     
    Last edited: Oct 19, 2018
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  15. Oct 19, 2018 #15

    Sockmonkey

    Sockmonkey

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    Considering the mass of batteries, it makes me wonder about the viability of sticking them on sliding racks for weight-shift control of pitch and roll.
     
  16. Jun 7, 2019 #16

    Nicholette

    Nicholette

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    So I may yet be able to make a 2/3 Gannet in the Garage?
     

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