I'm trying to develop the rib airfoils for a 1/12th scale model of the P2V-7. I use MacFoil to plot the ribs. Navy data give the root airfoil as NACA 2419; the tip is given as NACA 4110.5; offsets for these profiles are available from UofI data base. The model's 1/2 span is 70 inches; root chord is 12.5 inches; tip chord is 7.2 inches. Is there any approximate method for determining the proper profiles for the intermediate ribs (chords can be determined from the layout I've made) if they are spaced 3 inches apart? Any suggestions would be appreciated.

Dave P.