COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Teledyne Continental Motors Piston Engines
AD/CON/45
Amdt 3
Camshaft Oil Transfer Holes 11/96
Applicability: All IO-520-B, -BB, -BA, -C, -CB, -M, -MB; TSIO-520-B, -BB, -BE, -D, -DB, -E, - EB, -J, -JB, -K, -KB, -L, -LB, -N, -NB, -UB, -VB and -WB model engines
incorporating camshaft part number (P/N) 629726 or SA629726 with suffix lettering A through Z or AA or AB to the part number (eg. 629726 A or SA629726 AB).
Requirement: To prevent fatigue cracking in the oil transfer recess of the rear cam bearing resulting in fracture of the camshaft and subsequent engine failure:
- Remove from service all camshafts P/N 629726 or SA629726 with suffix lettering A through Z and AA.
2. a. Inspect P/N 629726 AB or SA629726 AB camshafts in the vicinity of the oil transfer recess of the rear cam bearing (see Figure 1) for evidence of defects, and
COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
2. b. Reject camshafts exhibiting any of the following defects:
(i) The radii at either end of the oil transfer recess is less than 0.762 mm (0.030 inches). Fig. 2, item 1 refers.
(ii) The radii at either end of the oil transfer recess is not continuous through 360 degrees of shaft rotation. Fig. 2, item 1 refers.
(iii) The oil transfer holes (2 off) are not approximately 90 degrees apart. Fig. 2, item 2 refers.
(iv) The oil transfer holes (2 off) cut into the radii at either end of the recess. Fig. 2, items 1 and 2 refer.
(v) Evidence of a rough surface finish and/or machine tool grooving in the oil transfer recess and around the oil transfer holes which could be considered as stress raising.
2. c. Following compliance with Requirement 2a and 2b; rework serviceable camshafts P/N 629726 AB or SA629726 AB in accordance with the procedures detailed in Teledyne Continental Motors Service Bulletin M86-14.
Compliance: 1. Unless previously accomplished in accordance with amendment 2 of this directive; at the next disassembly of the crankcase halves, effective on 10 October 1996.
2. Unless previously accomplished in accordance with amendment 2 of this directive:
* Installed camshafts: At the next disassembly of the crankcase halves, effective on 10 October 1996.
* Uninstalled camshafts (new or part life): Prior to installation in an engine, effective on 10 October 1996.
Background: This Directive was originally issued on 31 December 1984 to require the removal from service or inspection of certain part number camshafts. The requirement was in response to reports of engine failure events determined to have resulted from fatigue fracture of the subject part number camshaft. Amendment 1 was issued on 31 July 1985 to include camshafts manufactured by other than the engine manufacturer (PMA camshafts). Amendment 2 was issued on 31 July 1987 to reflect the manufacturer's issue of SB M86-14 on this subject. This amendment clarifies the inspection requirement and amends the compliance requirement from a "sunset" calendar date to an "at next access" requirement consistent with the manufacturer's published requirements.
Overview
The Civil Aviation Regulations 1998, enacted by the Australian Parliament, are the primary regulatory framework governing aviation safety in Australia. This legislation was introduced to address the need for a comprehensive set of regulations to ensure the safety and efficiency of civil aviation within the country. One particular aspect of these regulations is the issuance of airworthiness directives, which are binding instructions issued by the Civil Aviation Safety Authority (CASA) to ensure the continued airworthiness of aircraft and components. The directive pertaining to Teledyne Continental Motors Piston Engines, specifically AD/CON/45 Amendment 3, was enacted to address the problem of fatigue cracking in camshafts of certain model engines, which could lead to catastrophic engine failure. The policy objective behind these directives is to maintain and enhance aviation safety by mandating specific maintenance actions and inspections to prevent identified hazards.
Scope and Application
This legislative instrument, a Civil Aviation Safety Authority (CASA) Airworthiness Directive (AD), applies specifically to certain models of Teledyne Continental Motors piston engines used in aviation, namely the IO-520 series and TSIO-520 series engines with specific camshaft part numbers (P/N) 629726 or SA629726 with suffix letters A through Z or AA. The directive is designed to mitigate the risk of engine failure due to fatigue cracking in the camshaft oil transfer recess, which can lead to catastrophic failure. The AD mandates the removal from service of all camshafts with part numbers P/N 629726 or SA629726 with suffixes A through Z, and requires inspection and rework of camshafts with part numbers P/N 629726 AB or SA629726 AB under specific conditions. The geographic and jurisdictional reach of this AD is inherently tied to the Civil Aviation Regulations 1998, which are applicable throughout Australia, thereby ensuring that all aviation operations within the country comply with these safety directives. The AD does not explicitly state any exclusions or exemptions, indicating that it applies universally to the specified engines within the Australian aviation industry. Compliance with this AD is mandatory, with specific timelines and conditions outlined for both installed and uninstalled camshafts.
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39, establish the Airworthiness Directives under which AD/CON/45 Amendment 3 operates. This directive applies to Teledyne Continental Motors piston engines, particularly those with camshaft part numbers 629726 or SA629726 with suffix letters A through Z, AA, or AB (sections 1 and 2). The primary requirement (section 2) is to prevent fatigue cracking in the oil transfer recess of the rear cam bearing, which could lead to camshaft fracture and engine failure. To comply with this directive, all camshafts with part numbers 629726 or SA629726 suffixed A through Z and AA must be removed from service (section 2a). Additionally, camshafts with part numbers 629726 AB or SA629726 AB must be inspected for specific defects, such as insufficient radii at the oil transfer recess, discontinuities in the radii, incorrect positioning of the oil transfer holes, and surface imperfections (section 2b). If any defects are found, the camshafts must be rejected. Serviceable camshafts (629726 AB or SA629726 AB) must then be reworked in accordance with Teledyne Continental Motors Service Bulletin M86-14 (section 2c).
The obligations imposed by this directive are clear and specific. Operators of aircraft equipped with the affected engines must ensure that the required inspections and, if necessary, the removal and replacement of camshafts are carried out. For installed camshafts, this must occur at the next disassembly of the crankcase halves (section 1). For uninstalled camshafts, the inspection and rework must take place before they are installed in an engine (section 2). Compliance with these requirements is mandatory and must be achieved by 10 October 1996, unless the actions have already been completed in accordance with the previous amendments to this directive (sections 1 and 2).
Breaches of the requirements outlined in this directive may result in serious safety implications, including potential engine failure mid-flight. While the specific penalties for non-compliance are not detailed in the directive, violations of airworthiness directives generally attract significant penalties under the Civil Aviation Act 1988. These can include substantial fines and potential imprisonment, depending on the severity of the breach and its impact on aviation safety. The exact penalties would be determined by the Civil Aviation Safety Authority in accordance with applicable legislation.