AD FAA-2017-0020

We are adopting a new airworthiness directive (AD) for certain Honeywell International Inc. AS907 series turbofan engines. This AD was prompted by seven loss-of-thrust-control events attributed to water intrusion of the engine electronic control unit (ECU). This AD requires applying sealant to identified areas of the ECU and requires inserting a copy of certain airplane operating procedures into the applicable flight manuals. We are issuing this AD to address the unsafe condition on these products.