COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Piper PA-31 Series Aeroplanes
AD/PA-31/121
Amdt 1
Elevator Control System 5/94 DM
Applicability: Model PA31, PA31P, and PA31T series aircraft. Requirement: Accomplish the following inspections and procedures:
- Gain access to the elevator controls in the tail by removing the bottom half of the tailcone and the fuselage side panels.
2. Remove the long pushrod that connects the bellcrank and the elevator horn.
3. Secure the aft end of the bungee link to the elevator horn with safety wire for removal and installation of the bungee attach bolt.
4. Inspect, using a magnetic particle procedure, the rod end shank and threads for cracks. If found cracked, replace the rod end with a part number 49261-02 or 452- 658 rod end.
5. Visually inspect the bearing in the rod end for wear and free movement. If wear is found or the bearing will not move, replace the rod end with a part number 49261- 02 or 452-658 rod end.
6. Inspect, using a 10x magnifying glass, the forward attach holes in the pushrod for cracks, corrosion, or elongation. If cracks, corrosion, or elongation is found, replace the pushrod with a part number 40847-00, 40847-04, or 40847-07 pushrod, as applicable.
7. Visually inspect the forward and aft attach area to ensure that both a forward bolt, part number 402 311 (AN174-12A), and an aft bolt, part number 402 317 (AN174- 11A), are installed. If either one of these bolts is not installed, install the applicable bolt or replace the existing bolt with one of the applicable part number.
8. Remove the safety wire, reinstall the pushrod, check to ensure that the elevator rigging is correct, and reinstall the bottom half of the tailcone and the fuselage side panels.
COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Note 1: Figure 1 of this Directive illustrates the elevator assembly and the specific areas that are to be inspected.
Note 2: FAA AD 93-24-02 Rev 1 Amdt 39-8810 refers.
Compliance: Within 30 hours time in service after 9 March 1994.
Background: The FAA received a report of an incident where a Piper PA31T series aircraft experienced a complete loss of elevator control while in flight. An investigation disclosed that the aft control rod end bearing had separated into two pieces. Further investigation revealed a fatigue crack at the thread root, which extended through the rod end cross section.
Amendment 1 is issued in response to a revision of the relevant FAA AD, which corrects the figure (contained in the AD) to reflect the correct installation, and provides an alternate rod end part number.
Overview
The Civil Aviation Regulations 1998, enacted by the Parliament of Australia, is a comprehensive set of rules governing civil aviation safety, including the implementation of airworthiness directives to ensure the safety of aircraft operations. The 1998 Regulations introduced a structured approach to address the problem of ensuring that all aircraft meet specific safety standards to minimise risks associated with air travel. One such airworthiness directive, AD/PA-31/121 Amendment 1, targets Piper PA-31 series aeroplanes, specifically addressing issues with the elevator control system. This amendment was introduced in response to a reported incident where a Piper PA31T series aircraft lost elevator control due to a failure in the aft control rod end bearing. The policy objective behind this directive is to enhance the safety of aircraft by requiring specific inspections and corrective actions to prevent similar incidents in the future.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 105 Civil Aviation Safety Authority Schedule of Airworthiness Directives, applies to the Piper PA-31 series aeroplanes, including models PA31, PA31P, and PA31T. This directive mandates specific inspections and procedures concerning the elevator control system of these aircraft, ensuring that the components are in safe working order. The directive requires the removal and inspection of various parts of the elevator control system, such as the pushrod, rod end, and bungee link, to prevent failure and ensure safe flight operations. Compliance with these directives is mandatory within 30 hours of service after the effective date of the directive, which was 9 March 1994. This directive is applicable across the Commonwealth of Australia and aligns with international standards set by the Federal Aviation Administration (FAA) to enhance aviation safety.
The scope of this directive is limited to the specific models of Piper PA-31 series aeroplanes, and it does not extend to other aircraft types or models. The directive provides detailed steps for inspections and necessary replacements, ensuring that the elevator control system is thoroughly checked and maintained. This regulation ensures that all affected aircraft meet the required safety standards, reducing the risk of in-flight incidents. The directive is subject to amendments, which may be issued to correct figures or provide alternative part numbers to enhance safety and compliance, as seen in Amendment 1.
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39 - 105, include the Schedule of Airworthiness Directives, which governs the maintenance and inspection of aircraft, including Piper PA-31 series aeroplanes. Within this, AD/PA-31/121 Amendment 1 details the elevator control system inspection and maintenance requirements (Sections 1-8). This directive mandates that operators of PA31, PA31P, and PA31T series aircraft must perform detailed inspections and procedures on the elevator control system. This includes removing parts of the tail and fuselage to gain access to the elevator controls (Section 1), removing and inspecting specific components such as the long pushrod, rod end, and pushrod (Sections 2-7). All inspections must be conducted using specified methods and tools, and any defective parts must be replaced with parts of the specified part numbers.
Operators of the Piper PA-31 series aeroplanes are obligated to ensure compliance with the directive within 30 hours of the aircraft being in service after 9 March 1994. The compliance requirement is straightforward: operators must conduct the specified inspections and maintenance procedures on the elevator control system, ensuring that all components are free of defects and that any necessary replacements are made using the specified part numbers. Failure to comply with these requirements may result in the aircraft being deemed unairworthy, potentially leading to grounding until the necessary work is completed.
The Civil Aviation Regulations 1998 impose significant obligations on operators to maintain the airworthiness of their aircraft. Non-compliance with AD/PA-31/121 Amendment 1 can result in serious consequences. If an operator fails to perform the required inspections and maintenance on the elevator control system within the specified timeframe, it may result in the aircraft being deemed unairworthy. This could lead to enforcement actions by the Civil Aviation Safety Authority (CASA), including fines and potential criminal charges for operating an unairworthy aircraft. The maximum penalties for such offences can be substantial, reflecting the critical nature of maintaining the integrity of the aircraft’s control systems.