2009-11-01: Main rotor blades

2009-11-01 Eurocopter Deutschland GmbH: Amendment 39-15911. Docket No. FAA-2009-0453; Directorate Identifier 2008-SW-63-AD. Effective Date (a) This airworthiness directive (AD) becomes effective on June 12, 2009 Other Affected ADs (b) Supersedes AD 95-21-12, Amendment No. 39-9399, Docket Number 94-SW-19-AD (60 FR 53507, October 16, 1995). Applicability (c) This AD applies to Model MBB-BK 117 A-1, A-3, A-4, B-1, B-2, and C-1 helicopters, certificated in any category, with the following main rotor blade (blade) installed: Blade Part Number (P/N) Blade Part Number (P/N) 117-15001 117-150021 117-150061 117-151321 117-151341, 117-151341V001 117-151351, 117-151351V001 117-151361, 117-151361V001 117-151421V001 117-151441, 117-151441V001 117-151441V002, 117-151441V003 117-151451, 117-151451V001 117-151451V002, 117-151451V003 117-151461, 117-151461V001 Reason (d) Redesigned blades have become available that are not fitted with lead balance weights. Only a blade equipped with a lead balance weight may contain the unsafe condition. This AD retains the requirements of the current AD but limits the applicability to those part-numbered blades that are fitted with lead balance weights. The actions are intended to detect the blades fitted with lead balance weights that could move and cause severe vibrations leading to blade failure and subsequent loss of control of the helicopter. Actions and Compliance (e) Required as indicated: (1) Within 5 hours time-in-service (TIS), unless already done, and thereafter at intervals not to exceed 50 hours TIS, visually inspect the upper and lower surfaces of each affected main rotor blade (blade) in the area of the outboard lead balance weight in the marked inspection area for bulging. (i) If a marked inspection area is not visible, mark the area using a water-resistant and indelible marking pencil and then inspect the upper and lower surfaces of each blade in the area ofthe outboard lead balance weight for bulging. Note: For guidance, the current MBB-BK117 Maintenance Manual at Figure 14-5A contains the dimensions and placement of the inspection area. (ii) If bulging exceeds 1 millimeter (mm) (0.040 inch) in height, before further flight, remove the blade and replace it with an airworthy blade that is not listed in the applicability of this AD. (2) Replacing the affected blade with an airworthy blade that is not listed in the applicability of this AD is terminating action for the requirements of this AD. Differences Between This AD and the MCAI AD (f) We refer to flight hours as hours TIS. We retained the compliance time from the current AD and the Eurocopter ASB, dated August 18, 1994, and did not include the option of accumulating 1,800 flight hours since the first flight as stated in the MCAI. We do not incorporate ASB, Revision 3, damage inspection. We do not require that you contact ECD for instructions for corrective action. This AD requires that you contact the FAA for an Alternate Method of Compliance. Other Information (g) Alternative Methods of Compliance (AMOCs): The Manager, Safety Management Group, FAA, ATTN: Sharon Miles, Aviation Safety Engineer, Rotorcraft Directorate, Regulations and Guidance Group, Fort Worth, Texas 76193-0111, telephone (817) 222-5122, fax (817) 222-5961, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Related Information (h) European Aviation Safety Agency (EASA) AD No. 2008-0156, dated August 19, 2008, and Eurocopter Alert Service Bulletin MBB- BK117 No. ASB-MBB-BK117-10-108, Revision 3, dated August 7, 2008, contains related information. Air Transport Association of America (ATA) Tracking Code (i) ATA Code No. 6210 Main Rotor Blades.