Airworthiness Directive · Amendment 39-15411 · MD Helicopters, Inc. Model 600N Helicopters
MD Helicopters, Inc. Model 600N Helicopters
Superseded. A later AD replaced this one: AD 2008-20-05. Comply with the one in force.
Model 600N helicopters, serial numbers with a prefix “RN” and 003 through 058, that have not been modified in the fuselage aft section to strengthen the tailboom attachments and longerons per MD Helicopters (MDHI) Technical Bulletin (TB) TB600N-007, dated January 12, 2004; TB600N-007R1, dated April 13, 2006, or TB600N-007R2, dated October 5, 2006, certificated in any category.
This document supersedes an existing airworthiness directive (AD) for MD Helicopters, Inc. (MDHI) Model 600N helicopters. That AD currently requires interim initial and repetitive inspections of tailboom parts, installing six inspection holes in the aft fuselage skin panels, installing tailboom attachment bolt washers, modifying both access covers, and replacing broken attachment bolts. The current AD also provides for modifying the fuselage aft section as an optional terminating action. This amendment requires modifying the fuselage aft section within the next 24 months to strengthen the tailboom attachment fittings and upper longerons. The actions specified by this AD are intended to prevent failure of the tailboom attachment fittings, separation of the tailboom from the helicopter, and subsequent loss of control of the helicopter.
To prevent failure of the tailboom attachment fittings, separation of the tailboom from the helicopter, and subsequent loss of control of the helicopter, do the following:
(a) Modify the fuselage aft section to strengthen the tailboom attach fittings and upper longerons by following paragraph 2, Accomplishment Instructions, of MDHI TB600N-007R2, dated October 5, 2006, except you are not required to contact the manufacturer. This modification to the fuselage aft section is terminating action for the requirements of this AD.
(b) 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: Jon Mowery, Aviation Safety Engineer, Airframe Branch, 3960 Paramount Blvd., Lakewood, California 90712, telephone (562) 627-5322, fax (562) 627-5210, for information about previously approved alternative methods of compliance.
(c) Modifying the fuselage aft section shall be done by following the specified portions of MD Helicopters Technical Bulletin (TB) TB600N-007R2, dated October 5, 2006. 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 MD Helicopters Inc., Attn: Customer Support Division, 4555 E. McDowell Rd., Mail Stop M615, Mesa, Arizona 85215-9734, telephone 1-800-388-3378, fax 480-346-6813, or on the Internet at http://www.mdhelicopters.com. 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.
