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 CAR 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.
Airparts (NZ) Ltd. FU 24 Series Aeroplanes
AD/FU24/62 Forward Fin Structure 6/2002 DM
Applicability: All Model FU24, FU24A, -950, -950M, and -954.
Requirement: Referring to Figure 1, perform a detailed visual inspection of the forward area at the base of the fin for cracks. Pay particular attention to the skin in the area of the rivets that join the fin skin to bulkhead part number 242305, and aft to the first vertical lap joint. Inspect from the bottom of the fin up to the first external strap. To accomplish this inspection, any rubber abrasion protection that is fitted in this area, including any sealant, must be removed. The fin leading edge fairing, part number 242321, must also be removed.
If any structure is found cracked, repair before further flight.
Figure 1
Note: NZ CAA Emergency AD DCA/FU24/173 refers.
Compliance: Before 8 May 2002.
This Airworthiness Directive becomes effective on 1 May 2002.
Airparts (NZ) Ltd. FU 24 Series Aeroplanes
AD/FU24/62 (continued)
Background: The NZ CAA raised an airworthiness directive in response to a recent fatal accident where the aircraft’s fin separated in flight. Initial investigation revealed that the forward fin structure failed from fatigue cracks that were concealed beneath the rubber abrasion protection fitted to the fin. This Directive is considered interim action, pending completion of the investigation.
Steven John Swift
Delegate of the Civil Aviation Safety Authority 24 April 2002
The above AD is notified in the Commonwealth of Australia Gazette on 1 May 2002..
Overview
The Airworthiness Directive AD/FU24/62 issued in 2002 by Airparts (NZ) Ltd. under the authority of the Civil Aviation Safety Authority (CASA) addresses an identified safety issue concerning the forward fin structure of certain FU 24 Series Aeroplanes. This directive was enacted in response to a fatal accident where the forward fin of an aircraft separated in flight due to fatigue cracks hidden beneath the rubber abrasion protection. The policy objective is to ensure that all aircraft within the specified models undergo a thorough inspection and necessary repairs to prevent similar incidents. CASA issued this directive as an interim measure while investigations into the accident were ongoing, underscoring the importance of immediate action to rectify the unsafe condition. The directive requires a detailed visual inspection of the forward fin area and mandates repair of any detected cracks before further flight, to be completed before 8 May 2002.
Scope and Application
This Airworthiness Directive applies to all Model FU24, FU24A, -950, -950M, and -954 aircraft manufactured by Airparts (NZ) Ltd. The directive mandates that a detailed visual inspection be conducted on the forward area at the base of the fin for cracks, particularly focusing on the area of the rivets that join the fin skin to bulkhead part number 242305 and extending aft to the first vertical lap joint. The inspection must be performed from the bottom of the fin up to the first external strap, and any rubber abrasion protection, including sealant, must be removed, as well as the fin leading edge fairing, part number 242321. This action is necessary to address the unsafe condition identified following a fatal accident where the aircraft’s fin separated in flight due to concealed fatigue cracks beneath the rubber abrasion protection. The directive requires that any discovered cracks be repaired before further flight and must be complied with before 8 May 2002. The Airworthiness Directive was issued by Steven John Swift, a delegate of the Civil Aviation Safety Authority, and became effective on 1 May 2002.
Key Provisions
The main operative sections of this Airworthiness Directive (AD/FU24/62) pertain to the inspection and repair requirements for specific FU 24 Series Aeroplanes. Section 3 specifies the applicability of the directive to all Model FU24, FU24A, -950, -950M, and -954 aircraft. Section 4 outlines the requirement to conduct a detailed visual inspection of the forward fin structure, focusing on identifying any cracks at the base of the fin, particularly around the rivets that connect the fin skin to bulkhead part number 242305 and the area up to the first vertical lap joint. The inspection must be thorough, requiring the removal of rubber abrasion protection and sealant, as well as the fin leading edge fairing part number 242321. Section 6 provides the compliance timeline, mandating that the inspection and necessary repairs be completed before 8 May 2002, with the AD becoming effective on 1 May 2002.
The obligations imposed by this AD are specific and stringent. Aircraft operators must ensure that the visual inspection is performed meticulously, with all necessary parts removed to ensure visibility and accuracy. Any discovered cracks must be repaired prior to the aircraft's next flight. This directive places a clear responsibility on operators to act promptly and adhere to the detailed instructions to maintain the airworthiness of the aircraft. Additionally, operators must ensure compliance with the stipulated timeline, reflecting the urgency and safety implications of the directive.
Failure to comply with this Airworthiness Directive may result in severe consequences. Non-compliance could lead to unsafe conditions being perpetuated, potentially resulting in catastrophic failures such as the one that prompted this directive. While specific penalties are not detailed in this text, non-compliance with ADs generally can lead to enforcement actions by the Civil Aviation Safety Authority (CASA). These actions can include fines, suspension or revocation of airworthiness certificates, and potential criminal charges if the non-compliance results in accidents or fatalities. The severity of the penalties reflects the critical importance of adhering to ADs in maintaining aviation safety standards.