Airworthiness Directive · Amendment 39-11893 · MD Helicopters, Inc. Model MD-900 Helicopters
MD Helicopters, Inc. Model MD-900 Helicopters
Model MD-900 helicopters, serial numbers 0008 through 0068, certificated in any category.
Note 1: This AD applies to each helicopter identified in the preceding applicability provision, regardless of whether it has been otherwise 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 request approval for an alternative method of compliance in accordance with paragraph (c) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
This amendment adopts a new airworthiness directive (AD) for MD Helicopters, Inc. (MDHI) Model MD-900 helicopters that requires modifying the non-rotating swashplate assembly and re- identifying it and the swashplate assembly with new part numbers. This AD also requires creating a component history card or equivalent record to track the life of the newly identified non-rotating swashplate assembly and establishing a life limit of 1800 hours time-in-service (TIS). Additionally, this AD requires inspecting and modifying, if necessary, the longitudinal drive link assembly. This AD is prompted by reports of damage to the longitudinal drive link assembly caused by the sharp inner edge of the bushing in the non-rotating swashplate assembly. The actions specified by this AD are intended to prevent damage to the longitudinal drive link, loss of control of the main rotor system, and subsequent loss of control of the helicopter.
To prevent damage to the longitudinal drive link, loss of control of the main rotor system, and subsequent loss of control of the helicopter, accomplish the following:
(a) Within the next 100 hours time-in-service (TIS) or 3 months, whichever occurs first:
(1) Modify the non-rotating swashplate assembly, part number (P/N) 900C2010192-111, in accordance with the Accomplishment Instructions, paragraphs 2.A.(1). and 2.A.(2)., of MD Helicopters (MDHI) Service Bulletin SB900-071, dated January 10, 2000 (SB).
(2) Re-identify the swashplate assembly, P/N 900C1010004-125, as P/N 900C1010004-127, and the non-rotating swashplate assembly, P/N 900C2010192-111, as P/N 900C2010192-113 using contrasting color permanent ink. When the ink is dry, apply varnish over the P/N.
(3) Create or modify the existing component history card or equivalent record to track the life of the non-rotating swashplate assembly, P/N 900C2010192-113. Include the hours TIS accumulated when P/N 900C2010192-113 was identified as P/N 900C2010192-111.
(4) Visually and dye-penetrant inspect the longitudinal drive link assembly, P/N 900C2010212-101, for gouging and cracking in accordance with the Accomplishment Instructions, paragraph 2.B.(1). and 2.B.(2). of the SB except that returning scrap parts to MDHI is not required by this AD.
(i) If a crack is found, before further flight, replace the longitudinal drive link assembly, P/N 900C2010212-101, with an airworthy longitudinal drive link assembly.
(ii) If gouging is found, modify the longitudinal drive link assembly, P/N 900C2010212-101, in accordance with the Accomplishment Instructions, paragraph 2.B.(3). of the SB.
(b) This AD revises the Airworthiness Limitations
Section of the applicable maintenance manual by establishing a retirement life of 1800 hours TIS for the non-rotating swashplate assembly, P/N 900C2010192-113.
