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What is the aerodynamic advantage to a cuffed wing like this Cirrus? Cirrus SR-22

fooot
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Geoff
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1 Answers1

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Here we go: http://whycirrus.com/engineering/stall-spin.aspx

Spin Prevention
Cirrus chose, in the very earliest stages of designing the SR20 to take on the challenge: to minimize the risks associated with inadvertently stalling an airplane. The approach chosen was to employ wing technology developed by NASA reducing the potential for spin entry after an inadvertent stall. The most visible aspect is the discontinuous leading edge dividing the wing into distinct parts.
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How does this wing design work?
The outboard section of the Cirrus wing flies with a lower angle of attack than the inboard section. When the inboard section, which produces much of the lift, stalls the outboard section, where the ailerons are, is still flying. The result is that a stalled Cirrus airplane can be controlled intuitively using aileron.

fooot
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CrossRoads
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    That makes a lot of sense, nice find! It kind of makes me wonder why we don't see it on more designs though – Geoff Apr 06 '18 at 15:28
  • Reading the page, it seems to appear on other more current designs as well. I have micro-vortex generators on my plane that keep the airflow laminar in place longer with higher angle of attacks, keeps the airplane really responsive at low airspeeds and harder to stall. https://microaero.com/ They work really well, help to really shorten & soften my landings. – CrossRoads Apr 06 '18 at 15:58
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    Good luck to anyone that gets used to those handling characteristics when they next fly something that doesn't have this feature or lots of washout! – Toby Wilson Apr 06 '18 at 16:02
  • It's not hard to adapt. I had to fly an old Cessna 172 for a BFR so I could move my vortex generator equipped Cessna 177 on a ferry flight for a long overdue annual inspection. I hadn't flown in 13 years. The 172 was kind of doggy handling wise, compareed to the 177, and I had never flown one, but it was easy enough to stall it and recover, and the speed down final was similar. I just couldn't let it get quite as slow as I would in the Cardinal. – CrossRoads Apr 06 '18 at 16:10
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    @CrossRoads: Are you aware you keep posting broken links? It looks like you keep putting them in <> for some reason, and the > gets interpreted as part of the link. – user2357112 Apr 07 '18 at 01:19
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    @Geoff: It is a kludge that is slapped on a misbehaving wing after design. A better way is to design washout into the wing and to use different airfoils for the inner and outer wing. This step causes a jump in lift which is bad for induced drag. In short, the wing becomes less efficient in creating lift that way. – Peter Kämpf Apr 07 '18 at 08:07
  • I thought <> was what was used for links. What's the correct method? – CrossRoads Apr 07 '18 at 23:11