Airworthiness Directive · Amendment 39-18409 · Main rotor blades
MD Helicopters Inc., Helicopters
This AD applies to Model 369A, 369D, 369E, 369FF, 369HE, 369HM, 369HS, 500N, and 600N helicopters with an Aerometals main rotor blade attach pin (pin) part number (P/N) 369X1004-5 installed, certificated in any category.
We are adopting a new airworthiness directive (AD) for MD Helicopters, Inc. (MDHI), Model 369A, 369D, 369E, 369FF, 369HE, 369HM, 369HS, 500N, and 600N helicopters with a certain part-numbered main rotor blade attach pin (pin) installed. This AD requires ensuring the life limit of the pin as listed in the Airworthiness Limitations section of aircraft maintenance records and Instructions for Continued Airworthiness (ICA). If the hours time-in-service (TIS) of a pin is unknown, or if a pin has exceeded its life limit, this AD requires removing the affected pin from service. This AD was prompted by a report from an operator who purchased pins that did not have life limit documentation. These actions are intended to document the life limit to prevent a pin remaining in service beyond its fatigue life, which could result in failure of a pin, failure of a main rotor blade, and subsequent loss of control of the helicopter.
You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.
(1) Within 100 hours time-in-service (TIS) or during the next annual inspection, whichever occurs first:
(i) Review the maintenance records and determine the hours TIS of each pin P/N 369X1004-5 and whether there is a pin life limit listed in the Airworthiness Limitations Section of the applicable maintenance manual or Instructions for Continued Airworthiness (ICA). If the hours TIS on a pin is unknown, remove the pin from service.
(ii) For Model 369A, 369HE, 369HM, and 369HS helicopters, if there is no pin life limit, establish a new life limit of 5,760 hours TIS for each pin P/N 369X1004-5 by making pen-and-ink changes or by inserting a copy of this AD into the Airworthiness Limitations Section of the maintenance manual or the ICA. Remove from service any pin that has 5,760 or more hours TIS.
(iii) For Model 369D, 369E, 369FF, 500N, and 600N helicopters, if there is no pin life limit, establish a new life limit of 7,600 hours TIS for each pin P/N 369X1004-5 by making pen-and-ink changes or by inserting a copy of this AD into the Airworthiness Limitations Section of the maintenance manual or the ICA. Remove from service any pin that has 7,600 or more hours TIS.
(iv) For all model helicopters, add the following statement to the Airworthiness Limitations Section of the maintenance manual or the ICA by making pen-and-ink changes or by inserting a copy of this AD: If interchanged between different model helicopters, the life limit of pin P/N 369X1004-5 must be restricted to the lowest life limit indicated for the helicopter models and serial numbers affected.
(2) Do not install a pin P/N 369X1004-5 on any helicopter before the requirements of this AD have been accomplished.
