Airworthiness Directives; The Boeing Company Airplanes

We are adopting a new airworthiness directive (AD) for all The Boeing Company Model DC-6, DC-6A, C-118A, R6D-1, DC-6B, and R6D-1Z airplanes. This AD was prompted by a report of a fuel leak in a Model C-118A airplane that resulted from a crack in the wing lower skin. This AD requires repetitive radiographic, electromagnetic testing high frequency (ETHF), and electromagnetic testing low frequency (ETLF) inspections for cracking of the wing lower skin, and repairs if necessary. We are issuing this AD to address the unsafe condition on these products.