Hurricane Mk103

Discussion in 'The light stuff area' started by pictsidhe, Aug 6, 2018.

Help Support HomeBuiltAirplanes Forum by donating:

  1. Aug 6, 2018 #1

    pictsidhe

    pictsidhe

    pictsidhe

    Well-Known Member

    Joined:
    Jul 15, 2014
    Messages:
    6,859
    Likes Received:
    1,844
    Location:
    North Carolina
    The title should sum the idea up...
    My flying wing aerodynamics are proving to be tricky.
    I'm also a wee bit low on flying hours.
    So, perhaps, I should start with something with known passable flying qualities.
    After looking at a bunch of planes, the Hurricane seems to have a lot going for it.
    Decent plane to fly, good ground handling. Thick wing.
    Looks amenable to being flat wrapped in coroplast.
    Some initial researxh suggests the pilot cg is about 18" behind the cg full size. So I may need to move the cockpit a little. Otherwise, I think externally it will scale really well.

    What do you think of a 2/3 Hurricane 103?
     
  2. Aug 7, 2018 #2

    BJC

    BJC

    BJC

    Well-Known Member

    Joined:
    Oct 7, 2013
    Messages:
    9,549
    Likes Received:
    6,322
    Location:
    97FL, Florida, USA
    There have been several nicely done scaled Hurricanes, but none that I know of are close to a Part 103 machine. There always is room for another.


    BJC
     
  3. Aug 7, 2018 #3
  4. Aug 7, 2018 #4

    TFF

    TFF

    TFF

    Well-Known Member

    Joined:
    Apr 28, 2010
    Messages:
    11,640
    Likes Received:
    3,269
    Location:
    Memphis, TN
    The Loele 5151 was not 103, but there was always written spin that it might be if you wished hard enough. Its about double 103 weight empty. I bet it would be heavy in coreplass.
     
  5. Aug 7, 2018 #5

    pictsidhe

    pictsidhe

    pictsidhe

    Well-Known Member

    Joined:
    Jul 15, 2014
    Messages:
    6,859
    Likes Received:
    1,844
    Location:
    North Carolina
  6. Aug 7, 2018 #6

    WBNH

    WBNH

    WBNH

    Well-Known Member

    Joined:
    Oct 5, 2006
    Messages:
    305
    Likes Received:
    81
    Location:
    Portsmouth, NH
    Stumbled upon this replica just recently while researching something else. http://www.squadronleader.it/index_eng.htm 2/3 scale, and still 810 lbs empty.

    My Grandfather and Grandmother both lost brothers (my great uncles) in WWII...one in a 12th Air Force B-26 Marauder...one in a 504 Squadron Hurricane for the RAF. So I always had an idea for a light sport replica Hurricane. Don't know if there's enough wing area to scale it down to pt. 103 though, but it doesn't have to be true scale, but representative. Still a daunting task. I'll follow along if the project gets off the ground.
     
  7. Aug 7, 2018 #7

    pictsidhe

    pictsidhe

    pictsidhe

    Well-Known Member

    Joined:
    Jul 15, 2014
    Messages:
    6,859
    Likes Received:
    1,844
    Location:
    North Carolina
    Are there any WWII 103s?
    The Sindlingers look a bit dumpy to me, as if the scaling went wrong.
    2/3 is about as small as would meet stall and fit a human in the cockpit. Though likely more reclined to help cg and height. I'd prefer 3/4, but that would be harder to meer weigjt.
    Why heavy? 50m2 of 4mm coro weighs 37.5kg. 3mm is 30kg. Both are strong enough for a monocoque behind thw pilot. Wings will need spars. But the stuff is surprisingly rigid once curved. Closing the wings and fuse is something I haven't worked out yet.
     
  8. Aug 7, 2018 #8

    BBerson

    BBerson

    BBerson

    Well-Known Member HBA Supporter

    Joined:
    Dec 16, 2007
    Messages:
    12,051
    Likes Received:
    2,349
    Location:
    Port Townsend WA
    The good low powered ultralights are minimum 30' span. (Lazair 36')
    So go 3/4 scale or 7/8. And fabric was good enough for Hurricane. Fabric is obvious for ultralight. Or film, like Lazair.
    Use a plastic d-cell but fabric or film elsewhere.
     
    b7gwap likes this.
  9. Aug 7, 2018 #9

    TFF

    TFF

    TFF

    Well-Known Member

    Joined:
    Apr 28, 2010
    Messages:
    11,640
    Likes Received:
    3,269
    Location:
    Memphis, TN
    Its pretty heavy because it has to be used monocoque wise. Its as heavy as aircraft ply; thats OK, everything can have a use. But as a 103 material you want to use as little of a material as possible. A Tailwind wing panel weighs about 65 lbs, ready to fly; its sheeted with two 4x8 ply panels so about 15-18 lb are wing skin. A 103 wing panel needs to weigh 30 lb total ready to fly, and 25 would be ideal. I think a Legal Eagle is around 27. Just a lot of material that is suppose to be air. It adds up quick. Here is an old video of some old RC buddies flying a 1/4 scale Cub Like Trainer out of coreplast. https://www.youtube.com/watch?v=b32zxCiReNA At anything more than 1/2 throttle the whole thing would flutter.
     
  10. Aug 7, 2018 #10

    pictsidhe

    pictsidhe

    pictsidhe

    Well-Known Member

    Joined:
    Jul 15, 2014
    Messages:
    6,859
    Likes Received:
    1,844
    Location:
    North Carolina
    Wingskins in 3mm coro would be about 28lb.
    I'll have to do a lot of work yet and there are always compromises to be made. The LE is one place I may not manage to smoothly bend the coro. I have beautiful 4" radius curves. At beercan, not so great.
     
  11. Aug 7, 2018 #11

    BJC

    BJC

    BJC

    Well-Known Member

    Joined:
    Oct 7, 2013
    Messages:
    9,549
    Likes Received:
    6,322
    Location:
    97FL, Florida, USA
    The Sindlingers are what I was thinking of: http://1000aircraftphotos.com/Contributions/Lund/3732.htm With a Viking engine they would look more realistic, but probably not perform well.

    There was a plans seller named “WAR” or something similar that sold plans for a basic structure that could be configured as several different WW II fighters, some of which looked good.

    Edit: My neighbor recently relocated a 7/8th scale JU-87 to a museum. I saw the airplane at Oshkosh several decades ago, and it looked very realistic.


    BJC
     
  12. Aug 7, 2018 #12

    Tiger Tim

    Tiger Tim

    Tiger Tim

    Well-Known Member

    Joined:
    Apr 26, 2013
    Messages:
    2,867
    Likes Received:
    1,600
    Location:
    Thunder Bay
    The Sindlinger Hurricane is said to be true to scale with two exceptions: the canopy was enlarged four inches in every direction and the horizontal tail was increased by something like 12%. A friend has a very nicely finished one that I’ve sat in and can tell you that there is no space to shrink that canopy.
     
  13. Aug 7, 2018 #13

    ScaleBirdsScott

    ScaleBirdsScott

    ScaleBirdsScott

    Well-Known Member

    Joined:
    Feb 10, 2015
    Messages:
    1,033
    Likes Received:
    656
    Location:
    Uncasville, CT
    With a lighter duty wing, canopy delete, simple gear, 5gal header tank, Verner 3 cyl, and all fabric covering, the 1/2 scale Litefighters I'm doing should reach a 300lb empty weight. And that's with our current "heavy" frame. A further weight reduction program, and a 2-stroke on the front, and one could maybe approach the 254 goalpost.

    Our scaling of course is "generic WWII-ish fighter" that we then add some details and tweaks to give it the vibe of the bird of choice. This is especially true when you're talking fabric-covered and 300lbs empty where there's basically nothing going on inside.

    Unless the Hurricane was a particularly tiny fighter in real life (and, well, it was not) I really think 2/3 has inherently too much volume to realistically scrape down to UL weights. We butcher the heck out of our cockpit scaling in order to make 1/2 scale work but once you're down to that size and have the cockpit geometry fixed you just make the best of it and it ends up looking fine.
     
    blane.c likes this.
  14. Aug 7, 2018 #14

    TFF

    TFF

    TFF

    Well-Known Member

    Joined:
    Apr 28, 2010
    Messages:
    11,640
    Likes Received:
    3,269
    Location:
    Memphis, TN
    Scaling tail area to look right is very hard. RC scale builders know this. Back when scale competition used a ruler to measure correctness, most subjects were picked because they flew well without fudging. That process was too time consuming, so it went pure visual like the lower classes. More fudging and more exciting models built because. Aerodynamically just scale a plane and have it be ok is near impossible even a cub.
     
  15. Aug 7, 2018 #15

    radfordc

    radfordc

    radfordc

    Well-Known Member

    Joined:
    Feb 5, 2008
    Messages:
    1,236
    Likes Received:
    502
    There is a Corsair ultralight being developed in Germany. There is a video of it flying.
     
  16. Aug 7, 2018 #16

    pictsidhe

    pictsidhe

    pictsidhe

    Well-Known Member

    Joined:
    Jul 15, 2014
    Messages:
    6,859
    Likes Received:
    1,844
    Location:
    North Carolina
    Does anyone have a weight breakdown of a 103? Wing, fuse, gear etc.
    Why don't tails scale?

    I'm thinking 2/3 scale as that's about as small as I think I can go and make 24kts stall. Needs CL 2.0. Its also 26'8" span, which is getting a bit high on induced drag. Though some 103s (Minimax) are smaller. The Hurricane does have quite a lot of fuselage to complicate things. Unlike a 109, it has a very roomy cockpit. Yeah, I'll need to fit inside the canopy... The sindlingers are 5/8 scale, so I'd be a bit bigger.
    A full size mk1 was measured as CL 2.57 flaps and gear down, which I'm suspicious of. Clark YH tip airfoil, 19% YH root. Split flaps out to a bit past 1/2 span. XFLR5 was somewhat unimpressed with a YH scaled to 19%. Less lift as well as more drag. A 2219 (Typhoon) was even worse for cruise drag, but has a lot more lift. Meeting weight is first task. I have a nasty feeling the retracts may be stuck down...
     
  17. Aug 7, 2018 #17

    cluttonfred

    cluttonfred

    cluttonfred

    Well-Known Member

    Joined:
    Feb 13, 2010
    Messages:
    6,366
    Likes Received:
    2,231
    Location:
    World traveler
    I believe that a true Part 103 stand-off scale Hawker Hurricane could be done with a two-stroke engine and something like the Sky Pup construction method of light fabric over wood and foam, but it would be quite a major project to get that cantilever wing with ailerons done at that weight without exotic materials. Possible, but challenging. Personally, I'd suggest a MiniMax with an RAF paint scheme as a proven, affordable, solution. Looking out through a lightweight framed canopy you'll still feel like a WWII ace!
     
    Battler Britton likes this.
  18. Aug 7, 2018 #18

    ScaleBirdsScott

    ScaleBirdsScott

    ScaleBirdsScott

    Well-Known Member

    Joined:
    Feb 10, 2015
    Messages:
    1,033
    Likes Received:
    656
    Location:
    Uncasville, CT
    Yeah the gear are gonna be stuck down.

    Weight is pretty simple to figure out.

    Take 254, subtract engine/fwf weight, and that's what you have left to work with. Considering some long wings you're gonna be needing probably 1/3 of the remaining weight for those. 1/3 for fuselage. And 1/3 for hardware and controls and instruments and so on. Tweak as needed but that's what I've been seeing for our stuff.

    In my case I'm saying 300 lb empty, engine and fwf package is 90-100 lbs all up including exhaust and mount and oiltank and all. So let's assume 200 left over ive got 66 for fuse and 66 for wings and 66 for misc stuff. My center section is coming up in CAD as 33 and each outboard wing is 12+fabric so I think I'm right on target. Fuselage frame is 45 lbs. Empennage is 15lbs. All of that would need fabric. So pretty close. Then misc we got push/pull cables, and gear, seatbelt, and a cowling, some lightweight avionics and a fuel tank and some wiring and bam your done right about at 60lbs. Again.

    So factoring in some BS we would in theory be in the 300-ish range.
     
    pictsidhe likes this.
  19. Aug 7, 2018 #19

    WBNH

    WBNH

    WBNH

    Well-Known Member

    Joined:
    Oct 5, 2006
    Messages:
    305
    Likes Received:
    81
    Location:
    Portsmouth, NH
    That UL Corsair is intriguing...a case of using carbon fiber tubes in truss configuration (what has previously been labelled on these boards as metal-think.)

    It's an exercise in extreme engineering to wrap a shape of a Hurricane around ultralight construction. But that's kind of what Graham Lee and Robert Baslee have done. Airdrome's EIII can supposedly come in under ultralight limits. But he chose a simple aircraft to start with.

    If 103 weren't a factor, I can't help but imagine a series of cosmetic mods to a fastback Thatcher CX4 could impersonate a Hurricane (somewhat.)
     
  20. Aug 7, 2018 #20

    radfordc

    radfordc

    radfordc

    Well-Known Member

    Joined:
    Feb 5, 2008
    Messages:
    1,236
    Likes Received:
    502
    pictsidhe and ScaleBirdsScott like this.

Share This Page

arrow_white