>It’s the rear spar pickle forks which crack The cracks form in the outer chord of the rear pickle forks (Figure 1) and the behind lying safety straps, just whe

>It’s the rear spar pickle forks which crack The cracks form in the outer chord of the rear pickle forks (Figure 1) and the behind lying safety straps, just where they pass from the rear spar of the center wingbox to the fuselage side of the aircraft, Figure 2. >This is also the area where the fuselage side has a cutout to let the main landing gear strut fold in with its attached wheel. >The combination of a wing center-wingbox pushing wing and landing gear forces into the fuselage in an area where the fuselage has a large cutout for the folded main landing gear makes this area complex regarding forces and how these work the parts during flights. >The stress spectrum in the area can also have been affected by the later fitting of winglets on the NG, not foreseen in the original design of this area. >Winglets change the pressure distribution of the wing to a distribution spreading further outboard, by it increasing the wing root bending moment. https://leehamnews.com/2019/10/08/boeings-737-in-another-pickle-part-2/ https://leehamnews.com/2019/10/08/boeings-737-in-another-pic... So Boeing also made changes from the 737 to the 737 NG without complete reanalysis of how the changes affected all the parts?