Airworthiness Directives; Bell Helicopter Textron, Inc., Helicopters

We are adopting a new airworthiness directive (AD) for Bell Helicopter Textron, Inc. (Bell), Model 214B, 214B-1, and 214ST helicopters. This AD requires creating a component history card or equivalent record for certain pylon support spindle assemblies (spindles), establishes a new retirement life for spindles installed on Model 214B and 214B-1 helicopters, reduces the retirement life for spindles installed on Model 214ST helicopters, and requires replacing any spindle that has reached its airworthiness retirement life. This AD was prompted by three in-flight failures of the spindle that resulted in forced landings. The actions of this AD are intended to prevent failure of a spindle and subsequent loss of control of the helicopter.