AD/AC/84 Amdt 1 - Empennage Attachment

Overview

The Civil Aviation Regulations 1998, enacted by the Commonwealth of Australia, are designed to ensure the safety and efficiency of civil aviation within the country. Part 39, specifically, contains the Airworthiness Directives (AD) that must be adhered to by all aircraft operators. The AD/AC/84 Amendment 1, issued in 1995, addresses the issue of empennage attachment for specific models of the Twin Commander series aeroplanes, namely the Gulfstream/Rockwell/Aerocommander 500, 600, and 700. This amendment was introduced in response to reported problems of incorrect hardware, loss of torque on attachment bolts, and potential cracking in the tailplane attachment and fin lower ribs. The objective of this amendment is to ensure the continued airworthiness of these aircraft by implementing stringent inspection and maintenance protocols. The regulation is enforced by the Civil Aviation Safety Authority (CASA) and requires operators to inspect specific models of Twin Commander aeroplanes at designated intervals to ensure the structural integrity of the empennage attachments. For model 695B aircraft, inspections must comply with Gulfstream Aerospace Service Bulletin 206, while other models must adhere to Twin Commander Service Bulletin 218, Part I. Compliance with these inspection schedules is crucial to mitigate the risk of structural failure and ensure the safety of the aircraft and its occupants.

Scope and Application

The Civil Aviation Regulations 1998, specifically PART 39 - 105, focuses on the safety and airworthiness of the Twin Commander (Gulfstream/Rockwell/Aerocommander 500, 600, and 700) series aeroplanes, and applies to particular models with specified serial numbers. The regulations mandate inspections and modifications to address issues such as incorrect hardware, loss of torque on attachment bolts, and potential cracking of the tailplane attachment and fin lower ribs. The requirement applies to models 685, 690 to 690D, 695, and 695B, and compliance with the inspection schedule is crucial to maintain airworthiness. Inspections must be carried out before the aircraft reaches 2000 hours in service, with subsequent inspections at intervals not exceeding 12 months or 500 hours in service, whichever occurs first. The regulations are part of a broader framework managed by the Civil Aviation Safety Authority, and they are applicable nationally within Australia, ensuring that all relevant aircraft meet the specified safety standards.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105, mandates the issuance of the Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives. One such directive pertains to Twin Commander (Gulfstream/Rockwell/Aerocommander 500, 600, and 700) Series Aeroplanes, addressing the empennage attachment. This directive is applicable to certain models, namely 685, 690 to 690D, and 695 to 695B, with specified serial numbers as outlined in the Requirement Document. The directive requires inspections to be conducted according to specific service bulletins: Gulfstream Aerospace Service Bulletin (SB) 206 for model 695B, and Twin Commander SB 218, Part I, for models 685, 690 to 690D, 695, and 695A. Compliance with this directive necessitates that inspections be performed within prescribed timeframes. For model 695B aircraft, inspections must occur before the aircraft reaches 2000 hours of time in service. If these aircraft have been inspected previously in line with the original directive, a re-inspection must take place within 12 months or 500 hours of time in service since the last inspection, whichever comes first. Subsequent inspections should then occur at intervals not exceeding 12 months or 500 hours of time in service. For models 685, 690 to 690D, 695, and 695A, inspections must be conducted before 2000 hours of time in service. For model 685, this must occur either before 2000 hours or within 25 hours of time in service after 25 May 1995, whichever is later. If previously inspected, re-inspection should happen within 12 months or 500 hours since the last inspection, whichever is shorter. These inspections should continue at intervals not exceeding 12 months or 500 hours of time in service until the aircraft are modified in accordance with Twin Commander SB 218 Part II. The directive imposes clear obligations on the parties and entities it governs, primarily focusing on ensuring the airworthiness of specified aircraft models. Owners, operators, and maintenance providers must adhere to the inspection requirements detailed in the service bulletins. They must ensure that inspections are carried out diligently and within the prescribed timeframes to maintain compliance with CASA regulations. Failure to conduct these inspections could result in non-compliance with aviation safety standards, potentially leading to severe consequences for both the aircraft operator and passengers. In terms of penalties and consequences, while the directive itself does not explicitly state penalties, non-compliance with Civil Aviation Regulations 1998 can lead to serious outcomes. CASA has the authority to enforce compliance through various means, including administrative actions, fines, and more severe penalties. These could include grounding the aircraft, suspension of airworthiness certificates, or prosecution in a court of law. The exact penalties can vary depending on the severity and frequency of the non-compliance, but they are intended to ensure stringent adherence to safety directives to protect public safety in aviation.