AD 99-26-11 64 FR 71003

This amendment adopts a new airworthiness directive (AD), applicable to certain Bombardier Model DHC-7 series airplanes, that requires a one-time visual inspection to detect corrosion on the upper half of the lower longerons on the inboard nacelles; and corrective actions, if necessary. This AD also requires modification of the upper and lower longeron halves. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to detect and correct corrosion in the upper halves of the left and right hand lower longerons on the inboard nacelles, which could result in a landing gear failure.