COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Piper PA-24 (Comanche) Series Aeroplanes
AD/PA-24/24 Propeller Inspection and Operating Instructions 2/70
Applicability: Model PA-24 fitted with McCauley 2D36C14/78 KM-4 propellers.
Requirement: 1. Visually inspect blades for damage with the aid of a 10 power (2 1/2X) glass for defects such as erosion, scratches, nicks, cracks, etc. Rectify as necessary. After rectification dye penetrant inspect the entire blade from hub to tip.
Note: This work can be performed without removing the propeller from the engine.
2. Install a placard on the instrument panel adjacent to the RPM indicator reading as follows:
“AVOID CONTINUOUS OPERATION WHILE DESCENDING BETWEEN 2250 AND 2550 RPM WITH MANIFOLD PRESSURE SETTING BELOW 15 INCHES Hg”.
Note: McCauley Service Bulletin No. 76 also refers.
Compliance: Within 25 hours time in service after 29 January 1970.
Overview
The Civil Aviation Regulations 1998, as amended by the legislative instrument F2006B05522, introduce specific airworthiness directives for Piper PA-24 Comanche Series Aeroplanes fitted with McCauley 2D36C14/78 KM-4 propellers. This regulation was enacted to address safety concerns relating to propeller damage and operating instructions to prevent potential hazards during flight operations. The Civil Aviation Safety Authority, under the authority of the Australian Government, introduced these directives to ensure compliance with safety standards and to mitigate risks associated with propeller defects, as evidenced by the requirement for regular visual inspections and the installation of specific placards on the instrument panel. The policy objective behind these measures is to enhance flight safety and operational reliability by ensuring that aircraft are maintained to a high standard and that pilots are adequately informed of critical operational parameters.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 105, pertain to the Civil Aviation Safety Authority's (CASA) schedule of airworthiness directives for the Piper PA-24 (Comanche) series aeroplanes, with a focus on the AD/PA-24/24 Propeller Inspection and Operating Instructions for those fitted with McCauley 2D36C14/78 KM-4 propellers. The directive applies to all operators and owners of these aeroplanes, mandating that they ensure the propeller blades are visually inspected for any defects such as erosion, scratches, nicks, or cracks, using a 10 power magnifying glass. Any identified defects must be rectified, followed by a dye penetrant inspection of the entire blade from the hub to the tip. This inspection can be conducted without removing the propeller from the engine. Furthermore, operators are required to install a placard on the instrument panel adjacent to the RPM indicator, clearly stating the operational restriction to avoid continuous operation while descending between 2250 and 2550 RPM with a manifold pressure setting below 15 inches Hg. The directive mandates compliance within 25 hours of time in service after 29 January 1970, ensuring that the measures are promptly implemented for the safety of the aircraft and its occupants.
Key Provisions
The Civil Aviation Regulations 1998, under Part 39, include specific Airworthiness Directives (ADs) that govern the maintenance and operation of certain aircraft types. For Piper PA-24 (Comanche) series aeroplanes fitted with McCauley 2D36C14/78 KM-4 propellers, AD/PA-24/24 mandates critical operational and maintenance requirements. Section 1 of this directive requires operators to visually inspect the propeller blades for any signs of damage such as erosion, scratches, nicks, or cracks using a 10 power magnifying glass. Any detected damage must be rectified, and following the repair, the entire blade must undergo dye penetrant inspection from the hub to the tip. This inspection process can be carried out without removing the propeller from the engine, ensuring convenience and efficiency in compliance.
In addition to the inspection requirements, Section 2 of AD/PA-24/24 imposes an operational obligation on the operators. Specifically, a placard must be installed on the instrument panel adjacent to the RPM indicator. The placard must carry the warning: "AVOID CONTINUOUS OPERATION WHILE DESCENDING BETWEEN 2250 AND 2550 RPM WITH MANIFOLD PRESSURE SETTING BELOW 15 INCHES Hg". This warning is intended to prevent operational practices that could lead to propeller damage or failure. Furthermore, the directive references McCauley Service Bulletin No. 76, which provides supplementary guidance and information relevant to the compliance process.
Failure to comply with the provisions of AD/PA-24/24 can lead to serious consequences. The regulations do not explicitly state offences or penalties within the text provided, but non-compliance with airworthiness directives generally falls under broader aviation safety regulations. Under the Civil Aviation Act 1988, non-compliance with airworthiness directives can result in significant civil or criminal penalties. For instance, the operator could face fines or imprisonment if found to be in breach of safety regulations, as the ADs are integral to ensuring the continued airworthiness and safety of the aircraft. It is crucial for operators to adhere to these directives to avoid any potential legal repercussions and to ensure the safety of all personnel involved in the operation of the aircraft.