AIRWORTHINESS DIRECTIVE
For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.
Fokker F50 (F27 Mk 50) Series Aeroplanes
AD/F50/83 Grimes Aerospace Passenger Service Units 6/2003
Applicability: Model F.27 Mk.050 and F.27 Mk.0502 aeroplanes, all serial numbers (S/N), with Grimes Aerospace Passenger Service Unit (PSU) Part Number (P/N) 10-1178-XX (XX may be any number) installed.
Requirement: 1. Unless previously modified in accordance with either Grimes Aerospace Company Service Bulletin (SB) 10-1178-33-0140 dated 15 October 1993 or Revision 1 dated 25 March 1996, modify the Grimes Aerospace PSUs P/N 10- 1178-XX (XX may be any number) in accordance with SB 10-1178-33-0040 Revis ion 1.
2. Apply sealant to the aft air-conditioning duct ends in accordance with the Accomplishment Instructions of Fokker Services SB F50-25-055 dated 17 March 2003.
Note 1: Aeroplane S/N 20306, 20307, 20309, 20310 and 20312 had the air- conditioning duct sealant modification incorporated before delivery.
Note 2: CAA(NL) BLA 2003-035 (A) refers.
Compliance: For Requirements 1 and 2 - Within three years after the effective date of this Directive.
This Airworthiness Directive becomes effective on 12 June 2003.
Background: Over the years Fokker 50 operators have reported incidents of smoke in the aft passenger compartment during flight, apparently due to overheating of a PSU. Investigation has shown the overheating to occur due to water leakage onto the PSU electrical connector.
To address this problem, Fokker Aircraft issued a SB which recommended a one-time inspection of the PSU panels and, if leakage was detected, the cleaning of the connector and modification of the PSU panel. As the smoke problems appeared to be minor and were not considered hazardous at the time, the inspection and modification were not made mandatory. As a result, only few operators accomplished the inspection/modification on affected PSU panels.
Fokker F50 (F27 Mk 50) Series Aeroplanes
AD/F50/83 (continued)
Since the unsafe condition is still likely to exist or develop on other aircraft of the same type design, this Directive requires the modification of all PSU panels and the application of sealant on the aft air-conditioning duct ends.
Jim Coyne
Delegate of the Civil Aviation Safety Authority 29 April 2003
The above AD is notified in the Commonwealth of Australia Gazette on 21 May 2003.
Overview
The Civil Aviation Safety Authority (CASA) issued Airworthiness Directive F50/83 for the Fokker F50 (F27 Mk 50) Series Aeroplanes on 12 June 2003, in response to incidents of smoke in the aft passenger compartment during flight, which were traced to overheating of the Grimes Aerospace Passenger Service Units (PSU) due to water leakage. The directive mandates modifications to the PSU panels and application of sealant to the aft air-conditioning duct ends to correct the unsafe condition. The directive applies to all model F.27 Mk.050 and F.27 Mk.0502 aeroplanes with specified PSU parts installed. The objective of this Airworthiness Directive is to ensure that the identified safety issues are addressed to prevent potential hazards during flight. Compliance with the directive must be achieved within three years from its effective date.
Scope and Application
This Airworthiness Directive (AD) applies specifically to Fokker F50 (F27 Mk 50) Series Aeroplanes with all serial numbers that have a Grimes Aerospace Passenger Service Unit (PSU) Part Number (P/N) 10-1178-XX (where XX may be any number) installed. The AD mandates certain actions to address an unsafe condition identified in these aircraft, particularly concerning incidents of smoke in the aft passenger compartment due to overheating of the PSU, which is caused by water leakage onto the PSU electrical connector. The AD is applicable nationwide within the Commonwealth of Australia, issued by the Civil Aviation Safety Authority (CASA) delegate. The directive requires compliance within three years from its effective date of 12 June 2003. Notably, certain aircraft serial numbers had the air-conditioning duct sealant modification incorporated before delivery, as specified in the notes. The AD is effective as of the date of its notification in the Commonwealth of Australia Gazette on 21 May 2003, and it extends its application through subordinate service bulletins and instructions, ensuring that specific modifications and sealant applications are carried out as detailed.
Key Provisions
The Airworthiness Directive (AD) AD/F50/83 pertains specifically to Fokker F50 (F27 Mk 50) series aeroplanes with Grimes Aerospace Passenger Service Units (PSUs) Part Number 10-1178-XX installed. Section 1 of the AD specifies the applicability, which includes all F.27 Mk.050 and F.27 Mk.0502 aeroplanes, irrespective of their serial numbers, that have the mentioned PSU installed. Section 2 outlines the requirements that must be fulfilled to ensure compliance with this directive. The key requirement is that unless the PSUs have already been modified in accordance with Grimes Aerospace Company Service Bulletin (SB) 10-1178-33-0140 dated 15 October 1993 or its Revision 1 dated 25 March 1996, they must be modified according to SB 10-1178-33-0040 Revision 1. Additionally, sealant must be applied to the aft air-conditioning duct ends following the Accomplishment Instructions in Fokker Services SB F50-25-055 dated 17 March 2003. Notably, specific aircraft serial numbers have already incorporated the air-conditioning duct sealant modification before delivery.
The obligations imposed by this AD are stringent, demanding immediate attention to PSU modifications and air-conditioning duct sealant application. Operators must ensure that the specified modifications are completed within three years from the effective date of the directive, which is 12 June 2003. Failure to comply with these requirements could potentially compromise the airworthiness of the aircraft, leading to safety risks. Therefore, the directive aims to prevent the recurrence of incidents involving smoke in the aft passenger compartment, which is attributed to overheating PSUs due to water leakage onto the PSU electrical connector.
In terms of consequences, non-compliance with this AD can lead to serious legal and safety repercussions. The AD does not explicitly state penalties for non-compliance; however, failure to adhere to such directives typically results in the aircraft being deemed non-airworthy. This could lead to grounding of the aircraft until the required modifications are made, potentially causing significant operational disruptions and financial losses. Additionally, regulatory bodies, including the Civil Aviation Safety Authority (CASA), may impose further penalties, including fines or other administrative actions, to enforce compliance with aviation safety standards.