Enclosing an Evans Volksplane VP-2

Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by cluttonfred, Oct 26, 2014.

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  1. Nov 16, 2014 #41

    cluttonfred

    cluttonfred

    cluttonfred

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    Good, I didn't want you to think I was questioning your suggestions, only that I am not really qualified to say what's safe and what's not.
     
  2. Apr 25, 2016 #42

    cluttonfred

    cluttonfred

    cluttonfred

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    Here's a quick sketch of an enclosed VP-2 with a Gardan Minicab-style forward-hinged canopy. In the stock VP-2, the fuel tank is integral with the forward fuselage decking, all fiberglass, I was thinking I might make a reinforced bridge in that decking just aft of the tank through which to bolt the hinges along with a gusset of sorts to spread the load down to the longerons. I could see using one or two billet hinges or perhaps about 24" of stainless piano hinge since the decking is flat on top. That would actually put the hinge point further aft than what I have shown, between the instruments and the tank rear bulkhead, and therefore the windshield angle would a bit steeper, but this is just an initial sketch.

    enclosed vp-2.jpg vp-2 details sketch.jpg minicab_3v.jpg
     
  3. Apr 25, 2016 #43

    don january

    don january

    don january

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    With flat side's and top it would be easy to put a canopy like this one on the Taylor mono. taylor mono.jpg it would keep your weight down and IMO look better on the VP.
     
  4. Apr 25, 2016 #44

    cluttonfred

    cluttonfred

    cluttonfred

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    Thanks, DJ, did you mean something like these two? Honestly, I have yet to see a bubble canopy VP that I really liked.

    image.jpeg 2279131.jpg
     
  5. Apr 25, 2016 #45

    Tiger Tim

    Tiger Tim

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    The domed windscreens don't do it for me but a flat wrap windscreen with a big bubble canopy like a Canadian Chipmunk might be neat.
     
  6. Apr 25, 2016 #46

    don january

    don january

    don january

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    Yes I like them both
     
  7. Apr 25, 2016 #47

    cluttonfred

    cluttonfred

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    Here are several additional sketches....

    vp-2 cabin top flip forward.jpg vp-2 bubble canopy side hinge.jpg vp-2 bubble canopy side hinge 2.jpg vp-2 3-piece flat wrap side hinge.jpg vp-2 flat wrap opaque hood.jpg 50101d1461585951-enclosing-evans-volksplane-vp-2-enclosed-vp-2.jpg
     
    Last edited: Apr 25, 2016
  8. Apr 25, 2016 #48

    Tiger Tim

    Tiger Tim

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    This is a VP-1 but it's definitely not awful looking:
    [​IMG]
    I like that clever slot to allow the canopy rail to be below the strut, plus since it slides instead of hinging you can fly with the canopy open.
     
    don january, Himat and cluttonfred like this.
  9. Apr 25, 2016 #49

    BJC

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    You could be correct, but not all airplanes with sliding canopies can be flown with the canopy open.


    BJC
     
  10. Apr 26, 2016 #50

    Twodeaddogs

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    there's a new VP-2 video on Youtube and he has a very attractive forward sliding canopy, like the Robins and a high turtledeck. I also saw one which had a split side-hinging canopy like a Jodel 112, ie, light steel tube frame for the canopy and clad with 3mm Perspex. The VP-2 that I used to fly also had freely hinged underside gap seals for the ailerons, which improved their performance.
     
  11. Apr 26, 2016 #51

    cluttonfred

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  12. Apr 26, 2016 #52

    FritzW

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    Squared off bulkheads with fixed, transparent sides between them. All the canopy "monkey motion" happens above them. ...that looks looks like a good idea.
     
  13. Apr 26, 2016 #53

    cluttonfred

    cluttonfred

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    The Canadian registry says that VP-2 C-GTYL from the video above was built by Ron Cooper in 1979 and is now owned by James Scoles of Ottawa. Anyone know any more about it? I'm coming up empty for photos, other details.

    CCARCS-RIACC - Aircraft Details
     
  14. Apr 26, 2016 #54

    Twodeaddogs

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    that's the one. Looks very like the forward sliding canopy of the Robin types. Still looks fairly snug. I'd say rudder pedal control could be sporty, two up.
     
  15. Apr 26, 2016 #55

    cluttonfred

    cluttonfred

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    Then again, the classic open cockpit is certainly an option. And I think I like red. ;-)

    classic open VP-2 with extended turtledeck fairing.jpg
     
  16. Apr 26, 2016 #56

    Twodeaddogs

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    if you fly it as a single seater and the windscreen width is carefully chosen, then the cockpit is draught free.
     
  17. Apr 26, 2016 #57

    cluttonfred

    cluttonfred

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    I am sure that's true, but "carefully chosen" is hard to quantify. Anybody have any numbers or design guides for windscreens?
     
  18. Apr 27, 2016 #58

    Twodeaddogs

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    The first windscreen was two-person wide (full width of cockpit) but when it was realised that an 1834cc Vp-2 was no people carrier, the windshield was cut to about two-thirds width and the pilot sat in the centre. I often thought it could use Hurricane-style hinged doors to fill in the gap between the struts.
     
  19. Apr 27, 2016 #59

    cluttonfred

    cluttonfred

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    The VP-2 windscreen to plans is a little bit less than full width, basically the flat portion of the forward bulkhead between the rounded corners, because it is attached to the roll bar which is in turn attached to the forward strut attach points. See the plans here: http://www.wingsforum.com/aircraft/VP2/18.jpg. I have not seen a VP-2 with a windscreen only single-pilot wide, which would likely blow the wind right in your and your passenger's faces two-up. Even if it's not cross-country machine, that two-up capabililty for short hops is pretty much the whole raison d'être of the VP-2, unless you're of a size that you need that useful load for a single seater.

    FritzW and I have discussed modifying the roll bar by making it a full circular curve at the top, but starting lower down, which would raise the height of the rollover protection a few inches and allow the windscreen to reach the top of the roll bar without a gap. I also thought about making the roll bar out of an aluminum rather than steel tube so it would be less likely to mess with the compass. The plans say "3/4 in dia x .06 in wall stl tube" so, assuming that tube would normally be mild steel or 4130, can anyone tell me what wall thickness and what common alloy I should use for similar buckling strength in a 3/4" diameter aluminum tube? I suppose non-magnetic stainless steel might also be an option, but I'd still need some help on the alloy and wall thickness.
     
  20. Apr 27, 2016 #60

    FritzW

    FritzW

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    IF I'm reading the LPDH tube chart correctly, you can't get there with 3/4" aluminum (2024), even solid. You'd have to go with 7/8" x .120 at twice the weight.

    LPDH pg112.jpg

    It might be easier to move the compass...
     

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