2007-26-12: Blade skin debond

2007-26-12 Robinson Helicopter Company: Amendment 39-15314. Docket No. FAA-2007-0378; Directorate Identifier 2007-SW-04-AD. Applicability Model R22, R22 Alpha, R22 Beta, R22 Mariner helicopters, serial numbers 0002 through 4100; R44 helicopters, serial numbers 0001 through 1670; and R44 II helicopters, serial numbers 10001 through 11570, certificated in any category. Compliance Required as indicated. To detect main rotor blade (blade) skin debond and prevent blade failure and subsequent loss of control of the helicopter, do the following: (a) Within 10 hours time-in-service (TIS), unless accomplished previously: (1) Using a 10x or higher magnification, visually inspect for skin separation along the leading edge of any exposed (bare metal) blade skin aft of the skin-to-spar bond line on the lower surface of each blade. If there is any skin separation, the blade is unairworthy. (2) Perform a "tap test'' to detect any separation or void on the skin-to-spar bonded areas on the lower blade skin aft of the skin-to-spar bond line of each blade using a 1965 or later U.S. quarter-dollar coin. If there is any separation or any void, the blade is unairworthy. (3) Remove both blade tip covers. Using a 10x or higher magnification, visually inspect the blade tip area exposed when the blade tip covers were removed. "Tap test'' the skin to cap bond joints on both upper and lower surfaces. If corrosion, separation, or any void is detected, the blade is unairworthy. (4) Repaint any exposed area of the blade according to the Compliance Procedure, paragraphs 3 through 7, of R22 Service Letter SL-56 and R44 Service Letter SL-32, Revision A, dated March 29, 2007. (b) Before further flight, replace any unairworthy blade with an airworthy blade. (c) Thereafter, if the rotor blade has been found airworthy by the inspections in paragraph (a), before each flight, visually check for any exposed (bare metal) skin-to-spar bonded area on the lower surface of each blade within the outboard 24 inches paying particular attention to the last 10 inches before the tip. An owner/ operator (pilot) holding at least a private pilot certificate may perform this visual check and must enter compliance into the aircraft maintenance records in accordance with 14 CFR 43.11 and 91.417(a)(2)(V). If a pilot finds any area of skin bare metal in the outboard 24 inches of either blade, before further flight, a qualified mechanic must comply with the requirements of paragraph (a) of this AD. (d) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Contact the Manager, Los Angeles Aircraft Certification Office, FAA, ATTN: (For R22) Eric Schrieber, Aviation Safety Engineer, Aircraft Certification Office, Airframe Branch, 3960 Paramount Blvd., Lakewood, California 90712, telephone (562) 627-5348, fax (562) 627- 5210, or (for R44) Fred Guerin, Aviation Safety Engineer,Airframe Branch, 3960 Paramount Blvd., Lakewood, California 90712, telephone (562) 627-5232, fax (562) 627-5210, for information about previously approved alternative methods of compliance. (e) Repaint the exposed area of a blade by following Robinson R22 Service Letter SL-56 and R44 Service Letter SL-32, Revision A, dated March 29, 2007. The Director of the Federal Register approved this incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Robinson Helicopter Company, 2901 Airport Drive. Torrance, CA 90505, telephone (310) 539-0508, fax (310) 539-5198. Copies may be inspected at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html .(f) This amendment becomes effective on January 18, 2008.