MAIN WING STRESS ANALYSIS

Purpose

The purpose of this engineering calculation is to perform a stress analysis on the main wing of the P-36LF to verify the structural adequacy of the design.

Methodology

The spanwise stresses were calculated at 1-inch spanwise stations through numerical summation in order to account for spanwise variation in the structural geometry. The loads are resolved to vectors parallel and normal to the wing chord-line. The calc evaluates the load based on aerodynamic forces across the operating envelope based on the Riblett GA30-415 airfoil. The spanwise load distributions are calculated using XLFR5 quasi - CFD software. XFLR5 performs a 3-D panel method analysis using 2-D airfoil data coefficients calculated at various Re using the proven XFOIL code.

Results

The spanwise bending moment, normal shear, and torsional load for VA and VD, are shown below. The wing is strong enough for all design load conditions. Areas of greatest concern/least margin have been reinforced with 4140 steel.