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Deaf
2nd Mar 2003, 06:02
While browsing on the web I came across a replacement wing for the Zenith 701 which included a stress analysis for the wing.

http://www.dedaliusaviation.com/newdedalius/PDF/stress_analysis.pdf

I notice that the stress analysis assumes a constant span loading while looking at the aerodynamics myself the span loading would appear to be elliptical. As the wing has struts it would seem that the stresses (both bending and torsional) would be higher inboard of the strut than that assumed.

Is it normal to assume constant span loading for stress analysis?

Genghis the Engineer
2nd Mar 2003, 15:00
It's not normal but usually acceptable except in the one case of a strutted wing with the attachments a long way outboard, in which case you'll miss a buckling failure mode in the inboard section. Otherwise it's conservative and makes the maths very easy.

G