COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Fokker F50 (F27 Mk 50) Series Aeroplanes
AD/F50/74 Ground Idle Stop Assembly 6/97
Applicability: All Fokker F27 Mk 50 aircraft with serial numbers 20103 through 20317, 20321, 20324, 20327, 20329 and 20331.
Requirement : Modify the engine controls by installing a new ground-idle stop assembly and two placards in accordance with the accomplishment instructions of Fokker F50 Service Bulletin F50-76-016 dated December 20, 1996.
Note 1: RLD AD 1996-149(A) dated December 31, 1996, supersedes and cancels RLD AD 1996-128(A) dated October 31, 1996.
Note 2: A flight manual amendment correcting the “available accelerate-stop distance” initially required by RLD AD 1996-128(A) has been retained by RLD AD 1996-148(A) and is available from CASA on request.
Compliance: No later than 22 May 1998.
This Airworthiness Directive becomes effective on 22 May 1997.
Background: During flight tests of a Fokker F27 Mk 60 aircraft it was determined that the stop performance with rapid selection of reverse was less than expected. This condition also applies to the F27 Mk 50 aircraft.
The reduced performance is attributed to the slew-rate limiter that is a feature of the production propeller pitch control unit (PCU). The prototype PCU that was used during initial performance testing did not have the slew-rate limiter incorporated.
This directive provides a modification to the power levers and a revision to the flight manual to address this situation.
Overview
The Civil Aviation Regulations 1998, administered by the Civil Aviation Safety Authority (CASA), are designed to ensure the safety and efficiency of civil aviation in Australia. This legislative instrument includes a range of regulations governing aircraft operations, maintenance, and airworthiness, with the aim of protecting public safety and property from aviation-related risks. Specifically, PART 39 - 105 addresses airworthiness directives, which are legally enforceable rules that mandate compliance with specific safety standards and modifications to ensure aircraft meet the required safety standards. The directive AD/F50/74 concerning Fokker F50 (F27 Mk 50) Series Aeroplanes was enacted to address an identified safety issue where the stop performance during flight tests of Fokker F27 Mk 60 aircraft was found to be less than expected due to the slew-rate limiter in the propeller pitch control unit. This directive aims to rectify this issue by requiring the installation of a new ground-idle stop assembly and two placards, as detailed in Fokker F50 Service Bulletin F50-76-016, to be completed by 22 May 1998.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 105, apply to all Fokker F27 Mk 50 aircraft with specific serial numbers. These regulations mandate modifications to the engine controls to ensure compliance with airworthiness standards. The modifications include the installation of a new ground-idle stop assembly and two placards, as outlined in Fokker F50 Service Bulletin F50-76-016 dated December 20, 1996. Compliance with these directives is essential, with a mandated completion date of 22 May 1998. The directive became effective on 22 May 1997, superseding previous directives such as RLD AD 1996-149(A) dated December 31, 1996, which cancelled RLD AD 1996-128(A) dated October 31, 1996. A flight manual amendment correcting the "available accelerate-stop distance" has been retained by RLD AD 1996-148(A) and can be obtained from the Civil Aviation Safety Authority (CASA) upon request. These regulations are designed to address issues identified during flight tests, particularly concerning the performance of the stop function when rapid selection of reverse is required.
Key Provisions
The Civil Aviation Regulations 1998, specifically in Part 39 - 105, under the Civil Aviation Safety Authority Schedule of Airworthiness Directives, details the requirements for Fokker F50 (F27 Mk 50) Series Aeroplanes. In this context, AD/F50/74 outlines the modifications necessary for specific Fokker F27 Mk 50 aircraft models. The directive applies to all Fokker F27 Mk 50 aircraft with serial numbers ranging from 20103 through 20317, 20321, 20324, 20327, 20329, and 20331 (Section 1). The requirement is for these aircraft to undergo a modification to their engine controls. Specifically, a new ground-idle stop assembly must be installed, along with two placards, in line with the instructions provided in Fokker F50 Service Bulletin F50-76-016 dated 20 December 1996 (Section 2).
The obligations under this directive are clear and must be adhered to by the owners and operators of the specified Fokker F27 Mk 50 aircraft. Compliance with the directive necessitates the installation of the new ground-idle stop assembly and the appropriate placards, as per the instructions in the Fokker F50 Service Bulletin F50-76-016. This modification is to be completed no later than 22 May 1998 (Section 3). Additionally, operators must ensure that any flight manual amendments that correct the "available accelerate-stop distance" are implemented, as detailed in RLD AD 1996-148(A), which remains applicable and is available upon request from CASA.
Failure to comply with the requirements set out in AD/F50/74 may result in significant consequences. The legislation does not explicitly state the penalties for non-compliance; however, under general aviation regulations, failure to adhere to an Airworthiness Directive can lead to serious civil or criminal penalties. These may include fines, operational restrictions, or even the grounding of the aircraft until compliance is achieved. The exact penalties would depend on the severity of the non-compliance and any subsequent investigations by the Civil Aviation Safety Authority.
In summary, the AD/F50/74 requires specific Fokker F27 Mk 50 aircraft to install a new ground-idle stop assembly and appropriate placards, with compliance due by 22 May 1998. Non-compliance could lead to penalties ranging from fines to operational restrictions, underscoring the importance of timely adherence to the directive.