COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
DHC-2 (Beaver) Series Aeroplanes
AD/DHC-2/30
Amdt 1
Front Fuselage Struts at Windshield 13/99
Applicability: All model DHC-2 Mk. I and Mk. II “Beaver” and DHC-2 Mk. III “Turbo Beaver” aircraft.
Requirement: Accomplish either Requirement 1 or Requirement 2 below:
1. Replace installed front fuselage struts with replacement part number struts listed in the accompanying Table:
Installed P/N | Replacement P/N | Description |
C2FS209 or C2FS3281A | C2FS3281A | Strut Assembly Front Fuselage, Left |
C2FS210 or C2FS3282A | C2FS3282A | Strut Assembly Front Fuselage, Right |
Once replaced in accordance with the above requirement, struts have a life limit of 15 years from the date of installation in accordance with PSM 1-2-2, Part 5, Temporary Revision 2-22, and PSM 1-2T-2, Part 5, Temporary Revision 2T-6, both dated
3 August 1998.
2.a. Perform a detailed visual inspection of the front fuselage struts and all fittings attached to the frame for damage (corrosion, cracks, dents) using an inspection light, inspection mirror, and a 10x magnifying glass. On completion of the inspection, clean the drain holes around the bottom end fitting and protect the tube internally with an appropriate corrosion preventative spray (LPS #3 or equivalent recommended)
2.b. Perform an ultrasonic thickness measurement of all surfaces on the front fuselage struts. Although the inspection procedure detailed in Bombardier Service Bulletin 2/49 Revision C does not include inspection of the front fuselage struts, a procedure which follows a similar calibration procedure and measures strut thickness on all four surfaces at 25mm (1-inch) intervals is acceptable. There is a 100mm (4-inch) surface on the outboard side of each strut which is not accessible.
Replace any struts found below minimum thickness of 0.762mm (0.030 inch) before further flight; in accordance with Requirement 1 of this Directive.
Note 1: The 15 year life limit does not apply for struts inspected in accordance with Requirement 2 of this Directive.
Note 2: Transport Canada AD CF-98-37 R1 refers.
Compliance: 1. Before 30 April 2000, unless previously accomplished since 30 April 1985.
COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
The compliance of Requirement 1 of this Directive remains unchanged for this issue.
2.a. Initially, within 12 months after 30 December 1999, unless previously accomplished, and thereafter at intervals not to exceed 12 months.
2.b. Initially, within 24 months after 30 December 1999, unless previously accomplished, and thereafter at intervals not to exceed 5 years.
This Amendment becomes effective on 30 December 1999.
Background: Operators have reported numerous incidents of corrosion of the DHC-2 front fuselage struts on either side of the flight compartment windshield. These are structurally significant parts of the aircraft and inspection for corrosion is both difficult and work intensive. Bombardier/ de Havilland has published new life limits in the Recommended Overhaul or Replacement Schedule PSM 1-2-2, and PSM 1-2T-2.
Amendment 1 is issued in response to a revision of the related Transport Canada AD which introduces detailed visual and ultrasonic repetitive inspections as an alternative to the front fuselage strut 15 year life limit.
The original issue of this Airworthiness Directive became effective on 31 December 1998.
Overview
The Civil Aviation Regulations 1998, specifically Part 39 - 105, addresses airworthiness directives for various aircraft models, including the DHC-2 (Beaver) series aeroplanes, through the Civil Aviation Safety Authority (CASA). This legislation was enacted to ensure that civil aviation operations in Australia adhere to stringent safety standards, particularly in addressing structural issues identified in aircraft components. One such airworthiness directive, AD/DHC-2/30 Amendment 1, targets the front fuselage struts of DHC-2 Mk. I, Mk. II, and Mk. III "Turbo Beaver" aircraft. This directive responds to incidents of corrosion reported on these struts, which are critical to the aircraft's structural integrity. The policy objective is to mitigate the risks associated with structural failure by either replacing the struts with specified replacement parts or conducting detailed inspections and maintenance to ensure their continued airworthiness. Compliance with this directive is mandatory, with specific timelines provided for inspections and replacements to be carried out.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 105 concerning Civil Aviation Safety Authority schedules of airworthiness directives, addresses the maintenance and safety requirements for the DHC-2 (Beaver) series aeroplanes. This directive applies to all model DHC-2 Mk. I and Mk. II “Beaver” and DHC-2 Mk. III “Turbo Beaver” aircraft, ensuring they comply with stringent safety standards. The directive mandates compliance by either replacing the installed front fuselage struts with specified replacement parts or conducting a detailed visual and ultrasonic inspection of the struts. Replacement struts have a life limit of 15 years from the date of installation, a condition not applying to struts inspected under the detailed inspection requirements. Compliance timelines are set, with initial actions required before 30 April 2000 unless already completed since 30 April 1985, and subsequent inspections mandated at intervals not exceeding 12 months for visual inspections and 5 years for ultrasonic thickness measurements. This directive ensures the continued airworthiness of DHC-2 series aircraft by addressing corrosion and structural integrity issues.
Key Provisions
The Civil Aviation Regulations 1998, specifically under Part 39 - 105, detail Airworthiness Directives for DHC-2 (Beaver) series aeroplanes, focusing on front fuselage struts at the windshield. Section AD/DHC-2/30 Amendment 1 mandates that operators of DHC-2 Mk. I, Mk. II, and Mk. III aircraft must comply with one of two requirements to ensure airworthiness. Either the front fuselage struts must be replaced with specified replacement parts (Section 1), which have a life limit of 15 years from the date of installation, or a detailed visual inspection must be performed along with an ultrasonic thickness measurement of the struts (Section 2). The visual inspection must check for damage such as corrosion, cracks, and dents, followed by cleaning and corrosion prevention measures. If any strut is found to be below the minimum thickness of 0.762mm, it must be replaced before further flight.
The obligations imposed by this regulation require operators to ensure that either the specified replacement parts are installed or the detailed visual and ultrasonic inspections are carried out at prescribed intervals. For Requirement 1, compliance must be achieved before 30 April 2000 unless already done since 30 April 1985. For Requirement 2, the initial inspection must occur within 12 months after 30 December 1999, with subsequent inspections not exceeding intervals of 12 months for the visual inspection and 5 years for the ultrasonic thickness measurement. Failure to comply with these requirements can result in serious safety issues, as the struts are critical to the structural integrity of the aircraft.
Breaches of these regulations can result in significant consequences. While specific penalties are not detailed in the text, non-compliance with airworthiness directives generally attracts severe penalties under the Civil Aviation Act 1988. These can include fines, imprisonment, or both, depending on the severity and impact of the non-compliance. The exact penalties may vary, but the overarching goal is to ensure the highest standards of aviation safety are maintained, thus protecting passengers, crew, and the general public.