Commonwealth legislation

AD/DHC-8/6 - MLG Uplock Actuator

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Jurisdiction

Commonwealth

Collection

legislative instrument

Plain English Summary

4/10 complexity

Requires operators of DHC-8 aeroplanes (serial no. 3 onward) fitted with specified main landing gear (MLG) uplock actuator part numbers to inspect and, if necessary, rectify the uplock installation and to rework and re‑identify the actuators per the manufacturer’s service bulletin. The measure is intended to prevent a trapped uplock actuator target lever that can stop the main landing gear from releasing. Compliance deadlines: inspection within 50 hours’ time in service and rework completed by 28 February 1990; operators bear the cost and CASA enforces compliance.

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Current sections

Direct links to the current provisions in AD/DHC-8/6 - MLG Uplock Actuator.

AD/DHC-8/6 - MLG Uplock Actuator

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY

SCHEDULE OF AIRWORTHINESS DIRECTIVES

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Bombardier (Boeing Canada/De Havilland) DHC-8 Series Aeroplanes

AD/DHC-8/6 MLG Uplock Actuator 8/89

Applicability: Model DHC 8 serial number 3 and subsequent with MLG uplock actuator part numbers 10800-103, -105, -107, -109 and -111 installed, and which do not have modification 8/1098 incorporated.

Requirement: 1. Unless previously accomplished, inspect/rectify the MLG uplock installation in accordance with De Havilland SB No. 8-32-79 Revision A.

Rework and re-identify all uplock actuators in accordance with De Havilland SB No. 8-32-79 Revision A.

Note 1: Compliance with Requirement 2 constitutes terminating action for Requirement 1.

Note 2: Canadian AD CF-89-03 refers.

Compliance: 1. Within 50 hours time in service after 10 August 1989; repeat, prior to further flight, whenever the proximity sensor and/or proximity sensor mounting bracket on an uplock actuator has been reset or replaced.

Prior to 28 February 1990.

Background: A trapped MLG uplock actuator target lever may occur under adverse tolerance conditions combined with a failed target lever return spring. This occurrence will prevent the rotation of the main gear uplock latch and the release of the main landing gear.

Source text

Sourced from the Federal Register of Legislation (legislation.gov.au), CC BY 4.0.

1 AD/DHC-8/6 - MLG Uplock Actuator