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.
AlliedSignal (Garrett/AiResearch) Turbine Engines - TPE 331 Series
AD/TPE 331/61 1st Stage Turbine Disk 9/2004
Applicability: Honeywell International Inc. (formerly AlliedSignal Inc.) TPE331 series engines as detailed in Honeywell International Inc. Alert Service Bulletin (ASB) TPE331-A72- 2102, dated 28 March 2002, fitted with 1st stage turbine disk part number (P/N) 3101520-1 or P/N 3107079-1, with serial numbers (SNs) listed in Table 1 of Honeywell International Inc. ASB TPE331-A72-2102.
Note 1: These engines are installed on, but not limited to Mitsubishi MU-2B series, Construcciones Aeronauticas S.A. (CASA) C-212 series, Fairchild SA226 series (Swearingen Merlin and Metro series), Twin Commander 680 and 690 series (Jetprop Commander), Dornier 228 series, Beech 18 and 45 series, Beech Models JRB-6, 3N, 3TM, and B100, Cessna Aircraft Company Model 441 Conquest, and Jetstream 3201 series aeroplanes.
Requirement: 1. Unless previously accomplished perform a initial fluorescent penetrant inspection (FPI) of first stage turbine disks, P/N 3101520-1, in accordance with 2.A. (4)(a) through 2.A. (4)(d) of Accomplishment Instructions of ASB TPE331-A72-2102.
2. Perform repetitive FPIs of first stage turbine disks P/N 3101520-1 and P/N 3107079-1, in accordance with 2.B. (3)(a) through 2.B. (3)(d) of Accomplishment Instructions of ASB TPE331-A72-2102.
Note 2: First stage turbine disks, P/N 3107079-1, do not require initial inspection because they received an initial FPI and ECI at the time of conversion.
3. For first stage turbine disks that pass FPI, perform eddy current inspection (ECI).
Note 3: FAA AD 2004-09-29 Amdt 39-13619 refers.
Note 4: First stage turbine disks that pass FPI must be ECI before they are returned to service. Information on procedures for returning disks to Honeywell Engines, Systems, & Services, for ECI, can be found in ASB TPE331-A72-2102.
Compliance: For Requirement 1:
For first stage turbine disks with 4,100 cycles-since-new (CSN) or less, inspect at next access, but no later than 4,500 CSN.
AlliedSignal (Garrett/AiResearch) Turbine Engines - TPE 331 Series
AD/TPE 331/61 (continued)
For first stage turbine disks with more than 4,100 CSN, inspect at next access, but within 400 cycles-in-service (CIS) after the effective date of this AD.
For Requirement 2:
At each scheduled hot section inspection. For Requirement 3:
Before return to service following the FPI.
This Airworthiness Directive becomes effective on 2 September 2004.
Background: This Directive requires initial and repetitive FPIs and ECIs of the affected first stage turbine disks. This Directive results from a report of a first stage turbine disk found cracked at the disk bore. The crack originated from a localized; melt related, low- alloy area of the disk. Failure of the disk could lead to uncontained disk separation, resulting in engine damage and shutdown and damage to the aeroplane.
Bernard Malcolm Hole
Delegate of the Civil Aviation Safety Authority 9 July 2004
The above AD is notified in the Commonwealth of Australia Gazette on 11 August 2004.
Overview
The Airworthiness Directive AD/TPE 331/61, issued under subregulation 39.1 (1) of the Civil Aviation Safety Regulations 1998, was enacted in 2004 by the Civil Aviation Safety Authority (CASA) to address a critical safety issue concerning the Honeywell International Inc. (formerly AlliedSignal Inc.) TPE331 series engines, specifically the first stage turbine disks. This directive was prompted by the discovery of a cracked first stage turbine disk, which originated from a localized, melt-related, low-alloy area of the disk, posing a risk of uncontained disk separation and subsequent engine damage and aeroplane damage. The policy objective of this directive is to enhance the safety of aircraft by requiring mandatory inspections and maintenance actions on the affected turbine disks to prevent potential failures.
This Airworthiness Directive applies to specific Honeywell TPE331 series engines fitted with first stage turbine disks with certain part numbers and serial numbers. It mandates initial and repetitive fluorescent penetrant inspections (FPI) and eddy current inspections (ECI) for the identified disks. The inspections are to be performed at specified intervals, either based on the number of cycles since new or cycles in service, and before the disks are returned to service following an FPI. This directive became effective on 2 September 2004, ensuring that the required safety measures are implemented to mitigate the risk associated with the identified issue.
Scope and Application
This Airworthiness Directive (AD) issued under the Civil Aviation Safety Regulations 1998 by the delegate of the Civil Aviation Safety Authority (CASA) applies specifically to certain Honeywell International Inc. (formerly AlliedSignal Inc.) TPE331 series engines fitted with first stage turbine disks with particular part numbers and serial numbers. These engines are typically used in various aircraft models including the Mitsubishi MU-2B series, Construcciones Aeronauticas S.A. (CASA) C-212 series, and several others. The directive mandates the performance of initial and repetitive fluorescent penetrant inspections (FPI) and eddy current inspections (ECI) on the specified turbine disks to address a safety concern involving potential cracking. The directive outlines specific timeframes for inspections based on the cycle count of the engine since new or in-service. The AD became effective on 2 September 2004 and was subsequently notified in the Commonwealth of Australia Gazette on 11 August 2004. It applies across the Commonwealth and is enforced to prevent the risk of uncontained disk separation which could cause significant engine and aircraft damage.
Key Provisions
This Airworthiness Directive (AD), numbered AD/TPE 331/61, applies to specific Honeywell International Inc. TPE331 series engines installed in various aircraft models (section 1). These engines are identified by part numbers 3101520-1 and 3107079-1 and are listed in Table 1 of Honeywell International Inc. Alert Service Bulletin (ASB) TPE331-A72-2102. The AD mandates certain inspections and actions to address an identified unsafe condition related to the first stage turbine disks.
The AD imposes several obligations on the relevant parties, including the requirement to perform initial and repetitive fluorescent penetrant inspections (FPI) on the specified turbine disks (section 1). For disks with part number 3101520-1, an initial FPI must be conducted unless it has already been performed. This initial inspection must adhere to the instructions detailed in section 2.A. (4)(a) through 2.A. (4)(d) of the ASB TPE331-A72-2102. Additionally, repetitive FPIs must be carried out in accordance with section 2.B. (3)(a) through 2.B. (3)(d) of the same bulletin. For disks with part number 3107079-1, which already underwent initial inspection, only repetitive FPIs are required. Any disk that passes the FPI must undergo an eddy current inspection (ECI) before being returned to service.
In the event of non-compliance with the AD, there are potential civil and criminal consequences. Although the AD does not explicitly state penalties, non-compliance could result in severe safety risks, including uncontained disk separation, which could lead to engine damage, aeroplane damage, and possible accidents. The AD is issued under subregulation 39.1 (1) of the Civil Aviation Safety Regulations 1998, and any failure to adhere to its requirements may lead to enforcement actions by the Civil Aviation Safety Authority (CASA). These actions could include fines, penalties, and other regulatory measures.