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Regarding general aviation single engine high wing aircrafts in particular, what are the reasons for some of them to have no dihedral at all on their wing, or slight positive dihedral angle for other?

For instance, why do Piper J-3 Cub and Fiesler Fi 156 Storch both have no dihedral at all, when Zenair CH 701 and Cessna 172 display some slight positive dihedral?

And why aren't there any GA aircraft, high wing single engine, with slightly negative dihedral, like it is often seen with fighter aircrafts, such as F-104 (mid wing) or Harrier (high wing)?

Even if these examples were designed at different times, they all have wings with struts, so the reason cannot be structural, like at the time one straight wooden spar would have been more convenient.

(Piper j-3 Cub could be in the double-dihedral wing category, since its wingtips display dihedral, yet it is mainly one flat wing.)

quiet flyer
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user721108
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  • Yes this fully answers my question, thanks – user721108 May 10 '20 at 19:04
  • We could revisit this at a later date/question, not to delve into the "dihedral debate" for stability, but to evaluate side force balance in design. A little more dihedral will lessen spiralling tendency by helping balance forces above and below the vertical CG. The "Storch" and "Cub" were meant for short, daytime reconnaissance flights. The 172 was made for cross country cruising as well. A good study would be Lindburg's issues with the Spirit of St. Louis, which also may have had an undersized tail. – Robert DiGiovanni May 10 '20 at 23:03
  • "Weight low" makes for a horrible powered aerodynamic design (where do you put your thrust, at CG, Cdrag, somewhere between?). It seems to work for hang gliders, where active weight shift is used for control. Interestingly, the high wing design actually raises vertical CG, putting more area, there for aerodynamic drag underneath it(side forces, not induced drag). Early studies with free flight paper gliders showed putting the paperclip low caused difficulties in flight performance. A little dihedral and a "keel" makes for a surprisingly sound flyer. – Robert DiGiovanni May 11 '20 at 04:25
  • I wonder if Boeing ever considered just putting landing gear on the 314. "We can rebuild it, we have the technology". – Robert DiGiovanni May 11 '20 at 04:41
  • "(Piper j-3 Cub could be in the double-dihedral wing category, since its wingtips display dihedral, yet it is mainly one flat wing.)" -- I guess you are talking about the fact that the undersurface tapers up to the meet the top surface out near the tips? – quiet flyer May 11 '20 at 18:12
  • @quiet flyer that's it – user721108 May 11 '20 at 18:16
  • Great many thanks @quiet flyer – user721108 May 11 '20 at 18:27
  • @qq jkztd "double dihedral" perhaps might be dihedral wing with a Hoerner wingtip. The Hoerner wing tip is said to reduce drag and increase lift at higher AOA by deflecting the tip vortex away from the end of the wing. – Robert DiGiovanni May 11 '20 at 18:40
  • Here's the real reason why high wings have a built-in dihedral effect -- https://aviation.stackexchange.com/questions/12099/why-do-low-wing-aircraft-have-higher-dihedral-than-high-wing-aircraft/12101#12101 . Also 1st, 4th, 6th, and last paragraph of https://aviation.stackexchange.com/questions/53437/does-pendulum-effect-apply-to-hang-gliders-or-any-aircraft/56548#56548 . Also 5th and 8th paragraph and second footnote of https://aviation.stackexchange.com/questions/77971/when-a-paraglider-pilot-applies-brake-on-one-side-and-maintains-the-brake-pressu/77996#77996 – quiet flyer May 11 '20 at 18:43

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