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Old 02-23-2010 | 01:56 PM
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tomfiorentino
 
Joined: Dec 2007
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From: Upstate NY although I often wonder why...
Default RE: Spanwise Lift and Stall Sequence

Thank you for the replies.

To Matthews:  Then they must mean the angle of attack is highest at the root of the rectangular wing because of the vortex progression and downwash etc.  It is discussed in the book which is why I referenced the vortexes actually...I'm not that smart on my own.  Induced AOA is discussed also.  So to your point...they are referring to effective angle of attack.  I can understand that.  But I still can't get past the stated stall progression.  Why would a hersey wing stall last at the tips?  Seems to me the vortex would mess up flow and lift there first.  Also can't get past the reasons for the effective angle of attack differences between elliptical and tapered planforms.

I get the stall (at least I think I do), I get the flow separation and the discussion on pressure gradient.   I understand the visual that the tufting gives etc.  The book lays out lift and lift production from a pressure differential point of view and right or wrong leans toward the top of the wing
doing most of the work at normal angles of attack.  And from what I can see, there are differing opinions on some of that stuff.

But I can't seem to grasp the why behind the differences in the first stall region and the sequence of progression from there.  There is a blind spot somewhere in my thinking on this.  I'll go back and re-read some of this again.

To RMH: I hear what you are saying.  The book references the theoretical wing span of infinite length.  No problems.  All bets are off once you add the fuse and the tip.  But all things remaining equal..I am just trying to get the science behind the reality as we can't deny that airplanes with different wings exhibit different characteristics as a result.

To highplains:  I'll check it out.

Thanks