Airworthiness Directives; Eurocopter Deutschland GMBH (ECD) Model BO-105CB-5 and BO-105-CBS-5 Helicopters

This amendment supersedes an existing emergency priority letter airworthiness directive (AD), applicable to ECD Model BO-105CB-5 and BO-105-CBS-5 helicopters, that currently requires, before further flight, creating a component log card or equivalent record and determining the calendar age and number of flights on each tension- torsion (TT) strap. This amendment requires the same actions as the emergency priority letter AD and additionally clarifies the compliance time requirements specified in the emergency priority letter AD. This amendment is prompted by an accident in which a main rotor blade (blade) separated from an ECD Model MBB-BK 117 helicopter due to fatigue failure of a TT strap. The same part number TT strap is also used on the ECD Model BO-105 helicopter. The actions specified by this AD are intended to prevent failure of a TT strap, loss of a blade, and subsequent loss of control of the helicopter.