Figure 13. Test set-up for HEWT test at Southern Research. (a) Cross-sectional view of HEWT model pon testing and analysis correlation is included in reference[10]. Figure 15 presents typical the failure modes of the HEWT coupons. A large scatter in the joint failure load and failure mode data was noticed for this joint test. The predominant failure modes of the joint are "Delam" and "NSF". The delamination failure mode occurred at a lower load than the net-section failure mode for the coupons. Two coupons failed in a delamination only failure mode at an average test load of 59.829 kN. Four coupons failed in a net-section only failure mode at an average test load of 69.785 kN. The six coupons that failed by either delamination or a combination of the delamination or net-section failure modes failed at a test average of 64.785 kN. The pre-test progressive failure analysis predictions of the HEWT coupon was 66.674 kN which was within 1% of the average test failure coupon failure load. If the coupons that failed by net-section failure are not included in the comparison, then the pre-test predictions were still within 3% of the average test failure load for those six coupons. Post-test analysis failure predictions were not pursued since the (b) Actual FEM & simulation of boundary condition without end fixtures Figure 14. Finite element model description of HEWT coupon. w w w. s a m p e . o r g M AY/J U N E 2 0 2 0 | SAMPE JOURNAL | 19http://www.sampe.org