Cheap aircraft are simply impossible? :(

Discussion in 'Hangar Flying' started by Inverted Vantage, Nov 15, 2009.

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  1. Apr 5, 2019 #1221

    blane.c

    blane.c

    blane.c

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    A video of this plane.

     
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  2. Apr 5, 2019 #1222

    stanislavz

    stanislavz

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    Some technical question. For far103. How much power for level flight do you need for tube and fabric airplane in worst scenario (i.e a lot of wire bracing, pilot open to airstrem) and in best possible case ? I do see a lot of different numbers, like gypsy which flies with rotax 277. Or phantom x1, for whom 447 is minim motor.

    I still think that electric is the option now already. Not after better batteries tech someday..
     
  3. Apr 5, 2019 #1223

    blane.c

    blane.c

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    A video of the reproduction Jenny.

     
  4. Apr 5, 2019 #1224

    blane.c

    blane.c

    blane.c

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    For USA part 103 battery energy density will provide between 20 an 40 minutes of flight. If you built a experimental light like a 103 except for the additional weight of more batteries then of course you could have much more time.
     
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  5. Apr 5, 2019 #1225

    blane.c

    blane.c

    blane.c

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    Victor Serda has a facebook page. It is interesting, some techniques. There are a list of Victor Serda's from argentina on facebook his page is of the one with him standing next to an airplane. It would be easy for someone to ask for plans.
     
  6. Apr 5, 2019 #1226

    choppergirl

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  7. Apr 5, 2019 #1227

    stanislavz

    stanislavz

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    We have 120 kg plus bettery for same mass as fuel. So in total 135kg.

    20-40 minutes - on same plane different speed or in general ? Power rating ? 10-20kw or more ?
     
  8. Apr 5, 2019 #1228

    blane.c

    blane.c

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    WRONG! You have less than 254lbs and battery weight DOES NOT equate to fuel weight. Rainbow Aviation asked the FAA in a letter and the FAA's legal department responded. https://electricmotorglider.com/wp-content/uploads/2017/09/May-1-Letter-to-FAA-Legal-Counsel.pdf and https://rainbowaviation.com/wp-content/uploads/2017/08/elect-103-battry-def.pdf
     
  9. Apr 5, 2019 #1229

    blane.c

    blane.c

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    Dave Kramer and his Electric Lazair.



    After this is when the battery question was asked and answered.
     
  10. Apr 5, 2019 #1230

    Vigilant1

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    Last edited: Apr 5, 2019
  11. Apr 5, 2019 #1231

    blane.c

    blane.c

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    OOPS!
     
  12. Apr 5, 2019 #1232

    stanislavz

    stanislavz

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    No. I am from eu, got direct answer from our faa in letter. And yes, thouse 20kg is a game changer in ul category.

    But this just now. In whole eu there is no single legislation on this aspect. Uk have 300kg total unregulated. Even better for ev conversion.

    But back to topic. Quality and shapes - or you are have fully covered components and 5kw in cruise is ok ? Bu it adds weigth. Or you are not very nice from aerodynamic point, and needs more power.

    Could someone give numbers on required power for ul ?
     
    Last edited: Apr 5, 2019
  13. Apr 5, 2019 #1233

    Tiger Tim

    Tiger Tim

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    I'm really starting to like this Victor Serda guy...
     
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  14. Apr 5, 2019 #1234

    blane.c

    blane.c

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    Me too.
     
  15. Apr 5, 2019 #1235

    blane.c

    blane.c

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    Like the Kolb Flyer had originally two engines around 8 1/2hp each. The aircraft empty was about 185lbs and gross weight was not supposed to exceed 392lbs. It flew. Most upgraded power including Kolb and up to 15hp each from the factory though this added empty weight I am not sure what if any gross weight addition was added. Also I have seen pictures of the Kolb Flyer flying with two Kawasaki 440's.

    Lazair had two similarly sized engines originally, some have been upgraded to two 20-25hp engines. It is in the movie "The Gods Must be Crazy!" a enclosed version flying in Africa. The movie is a comic masterpiece.

    I have read on this forum many times it takes 20-28hp for an ultralight to fly. I have seen pictures and video of many flying with less power. Not a lot less. It depends on gross weight which depends on your weight, it seems ultralights are largely personal. Not much room for extra weight of adjustable seats and adjustable rudder pedals and etc. It seemed to me from observing video that the 17hp Kolb was fairly minimal but could have flown with a couple hp less not necessarily a comfortable couple of hp less.

    Sky Pup.

    http://machnone.com/specs.html

    Many have built it with less hp and they are on u-tube.
     
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  16. Apr 5, 2019 #1236

    Little Scrapper

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    Yeah, thinking the same thing.

    There's something really lovable about that parasol. It's intoxicating. Simple things usually are. I'd fly the schit out of that airplane.
     
  17. Apr 5, 2019 #1237

    Little Scrapper

    Little Scrapper

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    The world needs more "Skypups".

    Check out this photo of a Heath Parasol. There's something really beautiful about it. So clean, so simple. I'm completely obsessed by it for some reason.
    FB_IMG_1530070614130.jpg
     
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  18. Apr 5, 2019 #1238

    BJC

    BJC

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    Yes! Watching that, as well as the sequel, “The Gods Must Be Crazy II”, was an annual ritual on Thanksgiving evening for many years. I highly recommend it.


    BJC
     
  19. Apr 6, 2019 #1239

    choppergirl

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    My friend Mac just got his brother's powered Goat flying. Very minimalist plane, but not cheap imho if you put a $ PPG engine on it:


    Envious of way to store it - instead of removable or folding back wings, disconnect the tailboom. I bet you could put that on a hinge too, and just swivel it up against the back of a wing.
     
    Last edited: Apr 6, 2019
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  20. Apr 6, 2019 #1240

    stanislavz

    stanislavz

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    See same rating on ul - minimum is 20-25hp with low wing loading. More with higher wing loading and or draggy shape. Good turning point on sky pup.

    It still reasembles aeronca c2 at the wery begining - good shape and more like moto glider.

    To be dead simple - better earodynamic shape - more weigth , but cheaper power unit with possibility to go electric now.

    Some old school examples :
    https://en.m.wikipedia.org/wiki/Parnall_Pixie

    https://en.m.wikipedia.org/wiki/De_Havilland_Humming_Bird

    And please comparise it withhttps://en.m.wikipedia.org/wiki/RAE_Scarab

    Same wings, more weight and better clim rate with a little bigger motor.
     
    Last edited: Apr 6, 2019

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