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This is a theoretical question, the belt sander is an analogy to help visualize. How would a rectangular wing that is able to make its outer skin circulate around the airfoil perimeter perform?

Feasibility issues aside, would this contraption help delaying airflow separation at high AoA ?

enter image description here

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    $\begingroup$ One prototype of the yov-10a bronco had a rotating-cylinder-flap concept. It enabled a flap deflection to up to 80°, thereby postponning stall. The problem was, that a real wing is bending and therefore the rotating part of this flap has to be designed according to the experienced bending, which was a challenge. Found a report about the concept here: blackpony.org/v4-yov10a881nasarep.pdf $\endgroup$
    – Artur
    Commented Mar 21, 2022 at 10:40
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    $\begingroup$ Related? youtube.com/watch?v=hBq-gNkBZWw Also-- ultra-simple demonstration of rotating cylinder creating lift-- hold sytrafoam drink cup horizontally, open palm of one hand on top, open palm of other hand on bottom, give it a hard spin as you throw it, if spin direction is such that top surface is moving away from direction of travel (the more natural way to throw it), cup "flies" a long way, if spin direction is such that top surface is moving toward direction of travel, flight path curves sharply earthward and cup quickly hits ground-- $\endgroup$ Commented Mar 21, 2022 at 12:58
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    $\begingroup$ I find the belt sander hilarious in an aviation.se post. Look at it chillin'! $\endgroup$ Commented Mar 22, 2022 at 7:50
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    $\begingroup$ "now with included de-icing system" $\endgroup$
    – EarlGrey
    Commented Mar 22, 2022 at 14:12
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    $\begingroup$ Related : Flettner Rotor - related to the Magnus Effect $\endgroup$
    – J...
    Commented Mar 22, 2022 at 17:03

1 Answer 1

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RE "Feasibility issues aside, would this contraption help delaying airflow separation at high AoA?":

According to a team that tested it, yes:

The major advantages of a Magnus effect device are high-lift forces or rather high wing-loading and stall resistance [...]

Their design housed the treadmill in such a way that only the upper moving surface is exposed. According to their tables, they tested only up to 5° AOA. They acknowledge the complexity and added weight—and I'll add to that, reduced thrust and fuel capacity to power and house the system, respectively.

enter image description here

Side note: if the goal is not a novel STOL RC plane, one popular and tested method for high AOA is leading-edge root extensions (LERX).


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  • $\begingroup$ This is a great find, even if I don't get why they only test a small portion on the upperwing in the first place. Maybe it's the result of previous testings. $\endgroup$
    – user21228
    Commented Mar 22, 2022 at 8:34

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