From what I understand about the CWB is that the first models of J's had the exact same CWB that all other c-130 have. I heard that one of the first J's that rolled off the line went through a CWB inspection after a period of time just to see how it was handling, from what I heard is that it did not go as they would have thought. Since the J's nacelles and propellers are not as heavy and the J does not have externals(except the USCG), this ads more stress to the wing box, more wing flex from less weight holding the wings down. It seems that this was over looked in the design of the J's and it is good that it is getting fixed.
