AD 99-21-02 Amendment 39-11345

This amendment adopts a new airworthiness directive (AD), applicable to all Short Brothers Model SD3-30, SD3-60, SD3-SHERPA, and SD3-60 SHERPA series airplanes, that requires detailed visual and borescopic inspections to detect corrosion of the engine mounting tube assembly, and replacement of corroded parts with new or serviceable parts. 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 prevent failure of the engine mounting tube assembly, which could result in loss of the engine in flight.