COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 107 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Propellers - Fixed Pitch
AD/PFP/3
Amdt 3
Fairey Metal Propellers 10/88
Applicability: All Fairey Metal propellers. Requirement: 1. Daily Inspection:
Carefully examine the blade sheet for cracks on both sides and both edges in the region adjacent to the boss and identification stamping. This inspection may be made visually and without removing the propeller from the aircraft. Withdraw from service any propeller found to be cracked.
Note: Daily inspection may be performed and certified by the pilot or owner.
2. Half Overhaul Period Inspection:
Remove the propeller from the hub and the boss blocks from the blade sheet. Clean the blade sheet and inspect for cracks, particularly in the vicinity of the bolt holes and in regions where any fretting or corrosion has occurred. This inspection shall be made under strong diffused illumination using a suitable microscope with magnification in the range 15 to 25 diameters. Withdraw from service any propeller found to be cracked.
If no cracks are found, remove any fretting or corrosion from the blade sheet and boss blocks by means of coarse emery followed by fine emery.
Before re-assembly, ensure that the boss blocks are correctly fitted to the blade sheet using the blueing method. At least 80 per cent contact shall be achieved and at no place shall there be more than .002-in. clearance between boss blocks and blade sheet. This mating of surfaces shall be obtained without bolt pressure of any kind. A light tap with a mallet on the faces of the boss, which is held in alignment on the blade sheet by a suitable mandrel, is all that is permitted to obtain a blade marking.
3. Overhaul:
At the specified overhaul period, inspect and re- condition the propeller in accordance with Fairey Aviation Specification No. FAC1. In addition, carry out the following operations:
(a) Check fitment of boss blocks to blade sheet by the blueing method as prescribed in sub-paragraph 2 above.
(b) At each overhaul, anodise the propeller blade sheet and inspect for cracks. The anodic treatment shall be carried out in accordance with specification DTD 910 (latest issue) or other approved specification.
When above contact is achieved ensure any exposed bare metal is reprotected using Alodine or varnish as detailed in Fairey Aviation specification FAC 1.
COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 107 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Compliance: For Para. 1 - At each daily or overnight inspection.
For Para. 2 - Within 50 hours time in service of the mid- overhaul period.
For Para. 3 - Before installation in an aircraft following each overhaul completed after 30 August 1965.
Exemption: Notwithstanding the foregoing, propellers which have completed between 300 and 500 hours time in service since last overhaul before 30 August 1965 and have been inspected in that period in accordance with DCA Special Inspection Fairey/61/1 are hereby exempted from the inspection requirement of para. 2 during that current overhaul period.
Background: Recently a Fairey propeller was found assembled with barium chromate as the jointing compound. Use of an extrudable substance in this application can cause loss of hub bolt torque.
Overview
The Civil Aviation Regulations 1998, enacted by the Australian Parliament, form the fundamental legislative framework governing aviation safety in Australia. Part 39 of these Regulations includes the Schedule of Airworthiness Directives, which mandates specific maintenance and inspection requirements for various aircraft components to ensure airworthiness. The Airworthiness Directives aim to mitigate risks associated with aircraft operations by setting clear, enforceable standards. One such directive pertains to Fairey Metal propellers, established to address potential safety issues such as cracking and corrosion that could compromise the structural integrity of the propellers. These directives are enforced by the Civil Aviation Safety Authority (CASA), with a clear policy objective of enhancing flight safety through rigorous oversight and maintenance protocols.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 107, which outlines the Airworthiness Directives, applies to all Fairey Metal propellers. The regulations mandate a daily inspection of the blade sheet for cracks, particularly in areas near the boss and identification stamping, to ensure the propeller remains in a safe condition for use. This inspection can be conducted by the pilot or owner, and any propeller found to be cracked must be withdrawn from service. Furthermore, a half overhaul period inspection is required, involving a more detailed examination of the propeller’s condition, including inspection for cracks under strong diffused illumination and using a microscope, cleaning of the blade sheet, and refitting of the boss blocks with specific contact and clearance standards. At the specified overhaul period, a thorough inspection and reconditioning of the propeller must be carried out according to Fairey Aviation Specification No. FAC1, including anodising the blade sheet and inspecting for cracks. These inspections and maintenance activities are critical to ensuring the propeller meets safety standards before being reinstalled on an aircraft. The regulations also provide exemptions for certain propellers that meet specific service hour criteria and inspection standards.
Key Provisions
The Civil Aviation Regulations 1998, under Part 39 - 107, detail specific airworthiness directives that govern the maintenance and inspection of Fairey Metal Propellers. Section 107 mandates daily inspections for all Fairey Metal propellers, requiring a visual examination of the blade sheet for cracks, particularly in the region adjacent to the boss and identification stamping. Any cracked propeller must be withdrawn from service (107(1)). Additionally, a more thorough inspection is required every 50 hours of service time in accordance with the mid-overhaul period, where the propeller is removed from the hub, and the blade sheet and boss blocks are cleaned and inspected for cracks under strong diffused illumination using a suitable microscope. If cracks are detected, the propeller must again be withdrawn from service (107(2)). At the specified overhaul period, further detailed inspections and reconditioning must be conducted according to Fairey Aviation Specification No. FAC1, including checking the fitment of the boss blocks to the blade sheet and anodising the blade sheet for crack inspection (107(3)).
The regulations impose several obligations on the parties or entities governed by these directives. The primary obligation is the regular inspection and maintenance of Fairey Metal propellers to ensure they meet airworthiness standards. This includes daily inspections by the pilot or owner and more detailed inspections at specified intervals. Additionally, any repairs or overhauls must comply with the specified procedures and standards, such as those outlined in Fairey Aviation Specification No. FAC1. The regulations also require adherence to specific techniques, such as the blueing method for checking the fitment of boss blocks to the blade sheet and the use of approved specifications for anodising and reprotection of the blade sheet.
Failure to comply with these airworthiness directives can result in serious consequences. The primary concern is the safety risk posed by the use of non-compliant propellers, which could lead to in-flight failures and potential accidents. The regulations do not explicitly state penalties for non-compliance, but non-compliance with airworthiness directives can lead to severe civil or criminal penalties under the Civil Aviation Act 1988, including fines and imprisonment. The severity of these penalties underscores the importance of adhering to the prescribed inspection and maintenance procedures.