Airworthiness Directive · Amendment 39-15615 · MD Helicopters, Inc. Model 369A, OH-6A, 369D, 369E, 369F, 369FF, 369H, 369HE, 369HM, and 369HS Helicopters
MD Helicopters, Inc. Model 369A, OH-6A, 369D, 369E, 369F, 369FF, 369H, 369HE, 369HM, and 369HS Helicopters
Model 369A, OH-6A, 369D, 369E, 369F, 369FF, 369H, 369HE, 369HM, and 369HS, certificated in any category, with a tail rotor (T/R) blade installed as follows including all serial numbers and those T/R blades with an “M” or an “I” painted on the T/R blade root:
• Helicopter Technology Company, LLC (HTC) part number (P/N) 500P3100-101 and -103, or MDHI P/N 369D21640-501, -503, and -505.
• HTC P/N 500P3100-301 and -303, or MDHI P/N 369D21641-501, -503, and -505.
• HTC P/N 500P3300-501 and -503, or MDHI P/N 369D21643-501, -503, and -505.
• HTC P/N 500P3500-701 and -703, or MDHI P/N 369D21642-501, -503, and -505.
Note 1: An “M” or an “I” painted on the root of the T/R blade indicates compliance to an Alternate Method of Compliance (AMOC) to Emergency AD 2003-08-51 (Docket No. 2003-SW-17-AD, Amendment 39-13215, April 15, 2003), issued by the FAA, Los Angeles Aircraft Certification Office (LAACO) on June 13, 2003 to HTC. The AMOC addressed shot peening of the pitch horn of the T/R assembly.
This amendment adopts a new airworthiness directive (AD) for MD Helicopters, Inc. (MDHI) Model 369A, OH-6A, 369D, 369E, 369F, 369FF, 369H, 369HE, 369HM, and 369HS helicopters that requires repetitive tap inspections of each tail rotor (T/R) blade abrasion strip. This amendment is prompted by an incident in which an abrasion strip separated from a T/R blade. The actions specified by this AD are intended to prevent disbonding and subsequent separation of an abrasion strip from a T/R blade, which could result in vibration, loss of the T/ R, and subsequent loss of control of the helicopter.
To prevent disbonding and subsequent separation of an abrasion strip from a T/R blade, which could result in vibration, loss of the T/R, and subsequent loss of control of the helicopter, accomplish the following:
(a) Within 25 hours time-in-service (TIS), unless accomplished previously, and thereafter at intervals not to exceed 25 hours TIS, inspect the abrasion strip-to-skin bond integrity on each T/R blade using a tap test method in accordance with Part 1—Inspection, in Helicopter Technology Company, LLC (HTC) Mandatory Service Bulletin Notice No. 3100-4R4, dated May 10, 2006 (SB).
Note 2: MD Helicopters Service Bulletin SB369D-203R1, SB369E-097R1, SB369F-082R1, and SB369H-246R1, dated January 23, 2006, pertain to the subject of this AD.
(b) Modifying each T/R blade in accordance with FAA-approved data by installing a titanium rivet at the outboard end and painting the letter “T” on the root-end of the T/R blade to indicate the modification has been accomplished is considered a terminating action for the requirements of this AD.
(c) 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: John Cecil, Aviation Safety Engineer, 3960 Paramount Blvd., Lakewood, California 90712-4137, telephone (562) 627-5228, fax (562) 627-5210, for information about previously approved alternative methods of compliance.
