The 'daydreamers' thread...post your craziest designs and concepts here

Discussion in 'Hangar Flying' started by Floydr92, Apr 12, 2016.

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  1. Apr 17, 2016 #81

    Swampyankee

    Swampyankee

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    The "Flying Flapjack" (F5U) was a USN aircraft.

    What would be fun -- and possibly even achievable -- would be AVRO-Canada's flying saucer.
     
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  2. Apr 17, 2016 #82

    Victor Bravo

    Victor Bravo

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    WOW... and here I thought that I had a sketchpad full of interesting ideas. Bravo to you Delta!
     
  3. Apr 18, 2016 #83

    gtae07

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    That one popped into my head as I was finishing sketching out those other ideas. It's really appealing at the moment, too. The previous frontrunners were the QV-ish four seater sketched, and something sort of like a 2+2 RV-7 in performance and handling, but in composites for weight and drag benefits.

    Edit: I'll post some more sketches later (especially the wacky ones). I just have very little time at the moment--we have a new (well, six-week-old) baby at home and I'm just now figuring out how to do things outside of work and take care of him. And it's also amazing how much space such a little person takes up.
     
  4. Apr 22, 2016 #84

    gtae07

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    airplane concepts 2.jpg

    1. Twin-fuselage push-pull (great for in-laws or whiny kids)

    2. Three-engine V-tailed airliner

    3. All-metal canard (or with straight wing)

    4. Twin-engine for A-10 fans. Could also use pushers or ducted fans

    5. Electric racer (big honking motor and battery with radial-style cooling inlet and exhaust

    6. Slick pointy composite concept I first drew up in high school. Thought a wankel would be great then; now something like this in carbon with a TP-100 and a light fuel load would be a hell of a ride.
     
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  5. Apr 25, 2016 #85

    bifft

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    Posting two little ideas. I tend to build mine in x-plane, almost as easy as drawing up a picture and you can fly it around afterwards.

    The oldest is a thought of what to do if I somehow was gifted a jet engine. Intended as a cross country machine. One engine, two seats, lots of luggage room. Fooling around with this one in the sim taught me why jets always fly so high. Just run out of gas too fast down low.

    jet.jpg

    The second is a biplane, based on a silly idea I had and sketched out on my notepad at work one day. Start with 5 identical 10 foot span wing sections with hard points on the ends for mounting. Have two of them set up for ailerons (outermost two would work better, bottom two would be easier to build). As pictured, put a radial in it. The problem with this design is that the longest strut is in compression during positive G flight, so would need to be big/heavy.

    5panels.jpg

    Yes, I seldom bother to paint my x-plane designs.
     
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  6. Apr 25, 2016 #86

    cluttonfred

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    The jet looks a little wacky in terms of weight and balance to me, but the modular biplane has potential. How about using a sixth section (actually a third aileron section) upside down as the horizontal stab?
     
  7. Apr 25, 2016 #87

    nerobro

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    There's a few things I'd like to see. Mind, a few of these really don't have a good point... just... neat.

    First, I want to see a home built engine: In the ~100hp region. Piston might be neat, but I think turbine is easier for the homebuilder. Having fewer precision surfaces makes that a much more sane proposition. And at ~100hp, you can run it at near full rpm and get the best BSFC. By not needing spark, essentially as long as your fuel pump works, the thing will keep running. ... There's a lot to be said about turbines.

    I'd like to see a small twin: Twin VW, or similar, maybe, to make the weight work, a pair of paramotor engines. I can't say there's a good reason for it, beyond having something neat to fly. Hmm... This

    I'd like to see a pressurized homebuilt: Flying high, flying fast, you've got the ultimate time machine. Flying high enough lets you fly over most weather, making your passengers more comfortable. You'd need IFR, and potentially "flight into known icing". It would be a big deal airplane....

    I'd like to see a "big" homebuilt: Maybe eight seater? An RV with wings... And likely a float or seaplane. Take your family, and your best friends family for a flight. It would need to be something like 2000lbs useful load.

    A practical Chevy Smallblock V8 powered plane: Having a published, proven, working, engine installation would solve most of the auto conversion questions. "Use a corvette engine from 1994-1999" and "use a 1988-1992 camaro radiator" and "Here are the dimensions for a duct that provides adequate cooling at 60mph and 300hp" I'm pulling numbers out of my derriere at the moment, but that's the idea. Much like the inverted oldsmobile that wittman flew behind. Having a plane that's dependant on that engine setup ~garuntees~ the engine will fly, and prove it's worth or not.

    And so.. that's things I'd like to see. Some of these have even been plugged into calculators on my desktop once or twice. :)
     
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  8. Apr 25, 2016 #88

    rotax618

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    Like to build a smoothmobile.
     

    Attached Files:

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  9. Apr 26, 2016 #89

    bifft

    bifft

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    After posting it here, I had the same thought. Also, put ailerons on the bottom and top outer wings, using a slave strut to drive the top sections. Have the inner section also hinged for easy access to the front cockpit (assuming built as a two seater).


    If you put a "hard point" in the center of each module (also needed to use as a horizontal) you could end up with shorter/lighter struts. The lines aren't as pretty tho.



    You could also have a higher wing loading/faster model that just used two wing "modules" wire braced like a flybaby.



    Wings are easy enough to build that I doubt the modular wing would be worth the weight penalty vs. something more optimized for each part. Maybe something to "look easy to build" for the VP-21?
     
  10. Apr 26, 2016 #90

    PTAirco

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    You could optimize that a lot by re-positioning the struts; put the middle strut about halfway to two thirds out on the lower wing, cantilever it out from there. Outer strut can also be attached much closer inboard on the upper wing; no point in struts attaching to wingtips. There have been several biplanes with a compression strut running out and downward. Just have to do the sums to see if it's beneficial.
     
  11. Apr 27, 2016 #91

    leviterande

    leviterande

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    It is real. My first impression ever was that it has to be a fake but looking at the water spray, the handling.. it is real.

    Physics, at least, allowed this creation all ever since the great Stanely Hiller came up with the idea.


    [​IMG]

    [​IMG]

    You can buy off the shelf rc jets that produce the thrust required.(Zapatas has his own more powerful jets)

    At any rate, fake or not, the flight duration of this board is around 3 mins....

    Most astounding however is the power required according to him:

    1000hp!
     
  12. Apr 27, 2016 #92

    nerobro

    nerobro

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    Ooh, here's one I missed.

    A mach capable homebuilt.
     
  13. Apr 27, 2016 #93

    Tiger Tim

    Tiger Tim

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    You know what else would be cool? A Rotec powered two seat LSA Spartan Executive.
    [​IMG]
    You just have to argue that the retracts are a necessary safety feature making it a single use amphibian.
     
  14. Apr 27, 2016 #94

    Victor Bravo

    Victor Bravo

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    This has nothing to do with Hiller, this is the Williams Wasp, which was one of the earliest "aircraft" to use the Williams jet engine. It was evaluated by the military, and found to be easy enough to fly for an average soldier.

    Williams got a contract for cruise missile engines, never looked back, and the Wasp program is now a dim footnote in the company's history. You could easily build a Wasp-like contraption now, especially with Williams' newer and more efficient engines, but you'd need to be able to buy one of their engines first.:roll:
     
  15. Apr 27, 2016 #95

    bmcj

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    I can just imagine the specs...

    service ceiling - 10,000 feet
    payload - 250 lbs
    speed - 80 mph
    powered range - 30 ft
    glide range - whatever your altitude is
     
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  16. Apr 27, 2016 #96

    Aesquire

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  17. Apr 28, 2016 #97

    bifft

    bifft

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    Yes, but then you need to put those connection points into the wing, so it isn't 5 identical panels. Eventually it turns in to just optimizing a biplane. Which of course is what you would want to do if you were really going to go to all of the trouble of building it.
     
  18. Apr 28, 2016 #98

    leviterande

    leviterande

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    Indeed, the wasp was the first flying jet version.


    I believe Charles H. Zimmerman in the 1940s was the first ever ,in modern history at least, to conceive and test the idea of using your natural body kinesthetics to control, stabilize and fly any platform near effortlessly. As you can imagine, the idea was heavily laughed at first.

    First time they tested the idea was with a man on a simple thin air jet as seen in the picture. I remember reading that the pilot while standing on the board basically asked the operators why they weren't getting it to work or something like that. Their stunning reply was: you are already in the air. These tests took place before 1953 when the Hiller platform flew. The wasp came later based on the same principle.


    I was just waiting for someone with enough money really to put together modern rc turbines and stand on them. It would be surely fun but really expensive w/o range and any malfunction at forward speed would surely be a "kick":gig:
     
  19. Apr 30, 2016 #99

    nerobro

    nerobro

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    A pair of these ..... http://www.pbsvb.com/getattachment/...-motor-TJ-100/TJ-100-turbojet-engine.pdf.aspx

    That works out to 96lbs of engines. Figure 490lbs of thrust. Each engine sucks down about 45gph. This suddenly makes jets talking about "thousands of pounds of fuel" instead of gallons, make sense. Those engines would burn 540lbs/hr.

    So... i'm sure the Raymer spreadsheet breaks down much over 400kts... but that combination should do just over 700kts according to the spreadsheet. With nearly 500lbs of fuel onboard. It would need to be a frighteningly simple and light plane... something like the SubSonex. But with a high stall speed.

    Now I need to do some reading. Because there's so many things that feel a little off with this. For instance, it would probably need a variable intake for the jet engines. The tail would need to be all flying, due to the flow separation and change of CoL that happens. Would heating be an issue? I don't know.

    Off to the books... And off to find out who'd spend half a million dollars on a "well I can break mach" toy.
     
  20. Apr 30, 2016 #100

    cluttonfred

    cluttonfred

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    I'd love to see almost any non-helicopter VTOL approach come to life as viable homebuilt. I have always like the tailsitters, so maybe something along the lines of a scaled down Convair XFY-1 Pogo, perhaps with prone position pilot (so basically standing up for takeoff and landing).

    Convair_XFY-1_in_flight.jpg

    Something like the Hirth H30ES (102 hp, 45 kg) two-stroke should work for power. I have sketched out ideas for trying to address the obvious safety issues with a 360-degree crash cage around the pilot, prop brake or explosive destruction of the blades in an emergency, and a ballistic chute in the oversized spinner. Even simpler, but less attractive, would be a ballistic chute launching at 45-degrees up and forward with a guard to keep the lines out of the prop. There would still be an envelope in VTOL mode where you'd be too low for the chute, so that would have be dealt with as a crushable structure or, even better, airbags like a Mars lander. ;-)
     
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