96-06-12: Inspect Tail Rotor Blade & Abrasion Strip

96-06-12 BELL HELICOPTER TEXTRON, INC. : Amendment 39-9616. Docket No. 96-SW-01-AD. Applicability: Model 47B, 47B-3, 47D, 47D-1, 47G, 47G-2, 47G-2A, 47G-2A-1, 47G-3, 47G-3B, 47G-3B-1, 47G-3B-2, 47G-3B-2A, 47G-4, 47G-4A, 47G-5, 47G-5A, 47H-1, 47J, 47J-2, 47J-2A, and 47-K helicopters, with tail rotor blade assembly, part number (P/N) 047-642-117-105, serial numbers (S/N) A-1943 through A-2068, installed, certificated in any category. NOTE 1: This AD applies to each helicopter identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For helicopters that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must use the authority provided in paragraph (f) to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafecondition, or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any helicopter from the applicability of this AD. Compliance: Required as indicated, unless accomplished previously. To prevent premature delamination or separation of the tail rotor blade (blade) tip block or the abrasion strip, which could lead to failure of the blade and subsequent loss of control of the helicopter, accomplish the following: (a) Prior to the first flight of each day, visually inspect each blade tip, abrasion strip, blade skin and blade butt as follows: (1) Inspect each blade tip for corrosion or delamination adjacent to the abrasion strip and tip block. (2) Inspect each abrasion strip for corrosion or delamination, paying particular attention to the abrasion strip leading edge. (3) Inspect each blade skin for corrosion, paying particular attention to any areas of paint cracking or damage. Inspect all bonded joints for corrosion or delamination. (4) Inspect each blade butt around the bearings for corrosion or delamination. (b) Thereafter, conduct the visual inspections specified in paragraph (a) of this AD at intervals not to exceed 10 hours time-in-service. (c) If the inspections required by paragraphs (a) and (b) of this AD reveal any corrosion or delamination, replace the blade with an airworthy blade before further flight. (d) Installation of any airworthy tail rotor blade assembly which has been FAA-approved for the particular Model 47 helicopter, except for P/N 047-642-117-105 with S/N A-1943 through A-2068, constitutesa terminating action for the requirements of this AD. (e) Installation of tail rotor blade assembly, P/N 047-642-117-105M, including those with S/N A-1943 through A-2068, constitutes a terminating action for the requirements of this AD. NOTE 2: Bell Helicopter Textron Alert Service Bulletin No. 47-96-21, dated January 29, 1996, pertains to this AD. (f) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Rotorcraft Certification Office, Rotorcraft Directorate. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Rotorcraft Certification Office. NOTE 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Rotorcraft Certification Office. (g)Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the helicopter to a location where the requirements of this AD can be accomplished. (h) This amendment becomes effective on May 29, 1996, to all persons except those persons to whom it was made immediately effective by Priority Letter AD 96-06-12, issued March 13, 1996, which contained the requirements of this amendment.