Airworthiness Directives; Short Brothers Model SD3-60 SHERPA, SD3-SHERPA, and SD3-60 Airplanes

The FAA is superseding an existing airworthiness directive (AD), which applies to all Short Brothers Model SD3-60 and SD3-SHERPA airplanes. That AD currently requires an inspection of the fork end of the rear pintle pin on each main landing gear (MLG) to verify that sealant is properly applied and is undamaged, and related investigative/corrective actions if necessary. This new AD requires an additional inspection for correctly applied sealant on the MLG rear pintle pin assemblies, and related investigative/corrective actions if necessary. This AD also expands the applicability of the existing AD. This AD results from a new report of a cracked pintle pin fork end. We are issuing this AD to prevent stress-corrosion cracking and subsequent failure of the MLG.