Airworthiness Directives; McDonnell Douglas Model DC-8 Series Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-8 series airplanes, that requires a one-time eddy current conductivity test to determine the material type of the lower cap of the wing front spar; and modification of the lower cap of the wing front spar, if necessary. This amendment is prompted by reports of stress corrosion cracking in the forward tang of the lower caps of the wing front spar. The actions specified by this AD are intended to prevent such stress corrosion cracking, which if not corrected, could result in reduced structural integrity of the wing.