United States Government Publishing Office publisher pbl distributor dst United States National Archives and Records Administration Office of the Federal Register author aut Government Organization text government publication eng FR Regulatory Information 2012_register executive 2012-01-20 article Proposed Rules D09002ee1c7fda933 D09002ee1c7fda9b4 United States Department of Transportation originator org United States Government Agency or Subagency United States Federal Aviation Administration originator org United States Government Agency or Subagency We propose to adopt a new airworthiness directive (AD) for Agusta S.p.A. (Agusta) Model AB139 and AW139 helicopters with a certain generator control unit (GCU). This proposed AD was prompted by laboratory tests which revealed a potential fault in the overvoltage protection on a certain part-numbered GCU. This proposed AD would require replacing each affected GCU with an airworthy GCU. In addition, any affected GCU is not approved for installation on any helicopter. We are proposing this AD to prevent failure of the overvoltage protection of the GCU, degraded performance of the electrical power generation and distribution systems, a fire, and subsequent loss of control of the helicopter. 77 FR 2926 https://www.govinfo.gov/app/details/FR-2012-01-20/2012-1121 2012-1121 fr20ja12-9 RIN 2120-AA64 4910-13-P Docket No. FAA-2012-0013 Directorate Identifier 2010-SW-043-AD https://www.govinfo.gov/app/details/FR-2012-01-20/2012-1121 https://www.govinfo.gov/content/pkg/FR-2012-01-20/html/2012-1121.htm https://www.govinfo.gov/content/pkg/FR-2012-01-20/pdf/2012-1121.pdf Air Transportation Aircraft Aviation Safety Incorporation by Reference Safety 3 p. 2926 2928 77 FR 2926 Title 14 Part 39 14 CFR Part 39 RIN 2120-AA64 Airworthiness Directives; Agusta S.p.A. Helicopters; Federal Register Vol. 77, Issue PRORULE 2012-1121 DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 2012-03-20 Docket No. FAA-2012-0013 Directorate Identifier 2010-SW-043-AD 4910-13-P 2012-1121 Notice of proposed rulemaking (NPRM).

We propose to adopt a new airworthiness directive (AD) for Agusta S.p.A. (Agusta) Model AB139 and AW139 helicopters with a certain generator control unit (GCU). This proposed AD was prompted by laboratory tests which revealed a potential fault in the overvoltage protection on a certain part-numbered GCU. This proposed AD would require replacing each affected GCU with an airworthy GCU. In addition, any affected GCU is not approved for installation on any helicopter. We are proposing this AD to prevent failure of the overvoltage protection of the GCU, degraded performance of the electrical power generation and distribution systems, a fire, and subsequent loss of control of the helicopter.

We must receive comments on this proposed AD by March 20, 2012. Mark Wiley, Aerospace Engineer, FAA, Regulations and Policy Group, Rotorcraft Directorate, 2601 Meacham Blvd., Fort Worth, Texas 76137; telephone: (817) 222-5134; fax: (817) 222-5961; email: mark.wiley@faa.gov. Air Transportation Aircraft Aviation Safety Incorporation by Reference Safety Airworthiness Directives: Agusta S.p.A. Helicopters , mark.wiley@faa.gov http://www.agustawestland.com/technical-bullettins http://www.regulations.gov Vol. 77, no. 13 Office of the Federal Register, National Archives and Records Administration 2012-01-20 continuing daily deposited born digital 172 p. Table of Contents: AE 2.7: GS 4.107: AE 2.106: KF70.A2 https://www.govinfo.gov/app/details/FR-2012-01-20 P0b002ee181b07b47 0097-6326 0042-1219 0364-1406 769-004-00000-9 000582072 f:fr20ja12 https://www.govinfo.gov/app/details/FR-2012-01-20 https://www.govinfo.gov/content/pkg/FR-2012-01-20/pdf/FR-2012-01-20.pdf https://www.govinfo.gov/content/pkg/FR-2012-01-20/xml/FR-2012-01-20.xml fdlp 2905 3067 DGPO 2012-01-20 2024-06-03 FR-2012-01-20 machine generated eng FR FR-2012-01-20 77 13