Airworthiness Directives; Eurocopter Deutschland GmbH Model EC135 Helicopters

This amendment supersedes an existing airworthiness directive (AD), applicable to Eurocopter Deutschland GmbH (ECD) (Eurocopter) Model EC135 helicopters, that currently requires initial and repetitive visual inspections and a one-time dye-penetrant inspection of a certain main rotor hub shaft (shaft) for cracks, and replacement of any cracked shafts. This amendment requires the same actions as the existing AD, but corrects the shaft part number (P/N) in the current AD, includes additional P/N's, increases the area of inspection from a 40mm area to a 50mm area of the shaft, and provides an option for using either a visual or dye-penetrant inspection to satisfy the repetitive inspection requirement. This amendment is prompted by the need to correct the shaft part number and increase the area of inspection, as well as add additional affected shaft P/N's. The actions specified by this AD are intended to detect fatigue cracks in the shaft that could lead to shaft failure and subsequent loss of control of the helicopter.