AIRWORTHINESS DIRECTIVE
For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/PR/33 Amdt 1 and issues the following 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.
Propellers - Variable Pitch - Dowty Rotol
AD/PR/33
Amdt 2
Hub Assembly 1/2003
Applicability: All Dowty R389/4-123-F/25, R389/4-123-F/26, R390/4-123-F/27 propellers, incorporating hub part numbers 660714241, 660714255, and 660714241 hubs that have been salvaged per Dowty repair drawing number 660714259, fitted to SAAB SF340A or SF340B aircraft.
Requirement: Inspect affected propellers in accordance with Dowty Service Bulletin SF340-61-95, Revision 4.
Note: SB SF340-61-95, Revision 4, has been declared MANDATORY by the UK CAA.
Compliance: For propeller hubs with less than 7500 hours time in service since new, inspect prior to 8700 flight hours. Thereafter, re-inspect at intervals not to exceed 1200 flight hours.
Propeller hubs exceeding 7500 hours time in service since new, and which have completed less than 1200 flight hours time since the last inspection at the effective date of this Directive, carry out inspections at 1200 flight hour intervals.
Propeller hubs exceeding 7500 hours time in service since new, and which are in excess of 1200 flight hours since the last inspection at the effective date of this Directive, may continue to 1800 flight hours for the next inspection. Thereafter, re-inspect at intervals not to exceed 1200 flight hours.
This Amendment becomes effective on 23 January 2003.
Background: This Directive is prompted by reports of cracks in the rear hub wall in certain propeller hub assemblies. The inspection requires a check of the propeller retaining bolt torque and an ultrasonic inspection of the rear hub wall for cracks.
This Amendment reduces the repetitive inspection interval from 1800 to 1200 flight hours.
Propellers - Variable Pitch - Dowty Rotol
AD/PR/33 Amdt 2 (continued)
Amendment 1 of this Directive extended the initial and repetitive inspection intervals from 1600 hours to 1800 hours.
Amendment 1 of this Airworthiness Directive became effective on 28 December 2000. The original issue of this Airworthiness Directive became effective on 24 February 2000.
James Coyne
Delegate of the Civil Aviation Safety Authority 28 November 2002
The above AD is notified in the Commonwealth of Australia Gazette on 18 December 2002.
Overview
The Civil Aviation Safety Authority (CASA) issued the Airworthiness Directive (AD) AD/PR/33 Amdt 2 on 28 November 2002, which subsequently was revoked and reissued on 23 January 2003. This legislative instrument was introduced to address a problem related to reported cracks in the rear hub wall of certain Dowty Rotol variable pitch propeller hub assemblies, which could potentially lead to unsafe conditions in aircraft operations. The AD mandates specific inspection intervals and procedures to ensure the airworthiness of affected propellers fitted to Saab SF340A or SF340B aircraft. This legislative measure aims to maintain high safety standards in the aviation sector by ensuring that propellers are regularly inspected and maintained to prevent potential hazards. The AD was enacted under the authority of the Civil Aviation Regulations 1998, reflecting CASA's commitment to safety through regulatory oversight.
Scope and Application
The Airworthiness Directive (AD) AD/PR/33 Amdt 2, issued by the Civil Aviation Safety Authority (CASA) under the Civil Aviation Regulations 1998, pertains to specific Dowty Rotol propellers used on Saab SF340A and SF340B aircraft. This directive applies to all Dowty R389/4-123-F/25, R389/4-123-F/26, and R390/4-123-F/27 propellers that incorporate hub part numbers 660714241, 660714255, and 660714241 hubs, including those that have been salvaged as per Dowty repair drawing number 660714259. The directive mandates that inspections of these propellers be conducted in accordance with Dowty Service Bulletin SF340-61-95, Revision 4, which has been declared mandatory by the United Kingdom's Civil Aviation Authority. The compliance timeframes for inspections vary depending on the flight hours since the propellers were new and the last inspection, with intervals ranging from 1200 to 1800 flight hours. This AD became effective on 23 January 2003, revoking the previous Amendment 1 issued on 28 December 2000.
Key Provisions
The Airworthiness Directive (AD) AD/PR/33 Amdt 2, issued by the Civil Aviation Safety Authority (CASA) delegate, outlines specific requirements for the inspection of certain Dowty Rotol propeller hubs. According to section 1(a), these requirements apply to Dowty R389/4-123-F/25, R389/4-123-F/26, and R390/4-123-F/27 propellers with specific hub part numbers, fitted to SAAB SF340A or SF340B aircraft. The directive mandates that these propellers must be inspected in accordance with Dowty Service Bulletin SF340-61-95, Revision 4, which has been declared mandatory by the UK Civil Aviation Authority (CAA). This bulletin provides detailed instructions on the inspection process, including checks for the propeller retaining bolt torque and ultrasonic inspections for cracks in the rear hub wall.
The obligations under this AD are stringent and specific. For propeller hubs with less than 7500 hours of time in service since new, inspections must be conducted prior to reaching 8700 flight hours. For hubs that have exceeded 7500 hours but have less than 1200 flight hours since the last inspection at the directive's effective date, inspections must occur at intervals not exceeding 1200 flight hours. Propeller hubs with more than 7500 hours of service and more than 1200 flight hours since the last inspection at the directive's effective date may continue to 1800 flight hours for the next inspection, but subsequent inspections must be conducted at intervals not exceeding 1200 flight hours.
Breach of the requirements outlined in this AD can have serious consequences. Although the text does not explicitly state penalties, non-compliance with ADs is generally subject to strict enforcement under the Civil Aviation Act 1988 and the Civil Aviation Regulations 1988 (CAR). Failure to adhere to ADs can result in enforcement actions by CASA, which may include fines, suspension or revocation of aircraft operating certificates, or other regulatory sanctions. The seriousness of these potential penalties underscores the importance of strict compliance with the directive to ensure the continued airworthiness and safety of the affected aircraft.