AD FAA-2014-1058

We are adopting a new airworthiness directive (AD) for Airbus Helicopters (previously Eurocopter France) Model EC155B1 and AS 365 N3 helicopters with a certain automated flight control system (AFCS) and with a Garmin global positioning system (GPS) installed. This AD requires revising the Rotorcraft Flight Manual (RFM) to prohibit using the autopilot coupled with a Localizer/Instrument Landing System (LOC/ ILS) or Very High Frequency Omnidirectional Range (VOR) approach. This AD is prompted by a report of unpredictable and unexpected roll oscillations during coupled LOC or VOR approaches.This condition, if not corrected, could result in loss of helicopter control.