The determination of the effective resistance of a spindle supporting a model airfoil

W. E. Davidson, D. L. Bacon
naca-tn-37
Jan 1921


An attempt was made to determine the effect of spindle interference on the lift of the airfoil by measuring moments about the axis parallel to the direction of air flow. The values obtained are of the same degree as the experimental error, and for the present this effect will be neglected. The results obtained using a U.S.A. 15 wing (plotted here) show that the correction is nearly constant from 0 degrees to 10 degrees incidence and that at greater angles its value becomes erratic. At such angles, however, the wing drag is so high that the spindle correction and its attendant errors become relatively small and unimportant.

An Adobe Acrobat (PDF) file of the entire report:
http://naca.central.cranfield.ac.uk/reports/1921/naca-tn-37.pdf