Modern day "motorcycle of the air" aircraft class?

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Sraight'nlevel

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These are .....safer ?
 

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PiperCruisin

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peter hudson

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I am just wondering. If the pilot is leaning on the steer (which is a bit usual on a motorbike), how do you plan to steer pitch? Pushing forwards and backwards will really not be a good choice. Any chock on the pilot will be otherwise transferred into the steering.
Maybe a seat that slides to either side for roll control (ala early wright bros) and fore/aft for pitch; and the handlebars provide the fixed point for the pilot to steady himself and leverage his weight/seat around. Perhaps the bars steer a little for yaw, or just use foot controls for rudder. I think you'd have to set up a simulator to play around with what feels natural and motorcycle-like for 3 axis control.
 

nestofdragons

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nestofdragons

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Maybe a seat that slides to either side for roll control (ala early wright bros) and fore/aft for pitch; and the handlebars provide the fixed point for the pilot to steady himself and leverage his weight/seat around. Perhaps the bars steer a little for yaw, or just use foot controls for rudder. I think you'd have to set up a simulator to play around with what feels natural and motorcycle-like for 3 axis control.
There is a Japanese project with pilot on top of flying wing. He steers like that. It proofs to be possible. But i think a flightstick is more relaxing. I recall a flight in modern hangglider bi-SWIFT with flighstick while others flew modern hanggliders. It was gusty air. The other pilots came down with sore arms of handling the triangle under the hangglider. I felt no fatique of using the flightstick. I really prefer flightstick.
 
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J.L. Frusha

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Even simpler version of the flea broomstick.
MNXV0KA.png

Still two-axis, but using a Spratt wing setup instead of a moving rudder.
Fixed rudder plates on the rear wing tips give directional stability. They're also outside the pilot and prop tubulence, which is nice.
The flea's moving fore wing is already most of the way to being a spratt wing parts-wise. The wing just has to be made in left and right halves.
This way we have no control runs through the fuselage at all. Just a pair of pushrods coming off the stick straight to the wing. No moving bits aft of the pilot. The rear wing can easily be taken off in one piece, and the fore wing can be folded back just by unhooking the struts. Fuselage is still a single tube. Windshield is mounted on the center A-frame that supports the wing root.
I think we're at the limit of what we can shave off and still have a decent plane.
Might mod that to the slotted wing biplane...

 

nestofdragons

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Why has the Spratt103 never caught a bigger interest?
The designer has used a controversial manner to communicate, for sure, but the design, what is wrong with that or not?!
One of my contacts had correspondence with the designer. The designer was described as having a rather big ego. And ... what we feared, happened. He did not follow all the guidelines of our Flying Flea expert. Remember Spratt103 is basicly also a living wing, just like a Flying Flea.
The designer build it, flew it, crashed it. But ... he dares not to tell the reason. Sad.
 

rtfm

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I read a NACA report (don't remember the number) which concluded that independently pitching wings (like the Spratt 103) was divergent and wanted to spin if given half a chance. That's when I lost interest in it.
Also, the designer contacted me via email, and threatened to sue me because I had made some less than complementary remarks about his design. (On this forum, if I recall correctly).
 

cluttonfred

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There is a lot of myth and hyperbole surrounding freewing designs and a lot of people who see one or another approach as the magic bullet. There is no reason that the Spratt controlwing couldn't work as a simple two-axis aircraft as long as the CG was placed such that the tail was lifting and the wing loading substantially higher on the front wing than on the back wing. The problem I see with the Spratt design is that you lose control in both axes, at least momentarily, when the front wing stalls.

For that reason I prefer the Mignet approach, which is not a true freewing because the incidence of the front wing is set by the position of the stick or yoke, though it approaches it (and Mignet claimed some alleviation of the rough ride in turbulence) if the pilot keeps a light hand and allows the wing to absorb the buffeting. The advantage of the Mignet approach is that the separate rudder (whether actuated by stick or yoke or pedals) provides directional/lateral control regardless of the front wing's state and you are unlikely to get a wildly asymmetric stall of the front wing since it's all one piece with no control surfaces.
 

erkki67

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One of my contacts had correspondence with the designer. The designer was described as having a rather big ego. And ... what we feared, happened. He did not follow all the guidelines of our Flying Flea expert. Remember Spratt103 is basicly also a living wing, just like a Flying Flea.
The designer build it, flew it, crashed it. But ... he dares not to tell the reason. Sad.
Did the designer crash?

I’ve heard of one gentleman crashing it, but according the designer , the builder and pilot integrated non approved modifications to his build , which led to the crash.

The later, I’ve only the designers point of view.

But the overall concept remains intriguing, but I’d add a ruder to it like the ULX from Argentina.
 
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