COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Pratt and Whitney Piston Engines
AD/PW-P/18
Amdt 1
R1340 PMA Crankshaft 6/98
Applicability: Pratt and Whitney R1340 engines incorporating an Air Tractor, Inc. PMA crankshaft, P/No 90114.
Note 1: This Directive is only applicable to engines that have had the crankshaft replaced with a PMA shaft, P/No 90114, during overhaul or repair since
12 September 1991.
Requirement: 1. Inspect the crankshaft counterweights in accordance with Snow Engineering Service Letter No. 135.
2. Rework crankshaft counterweights in accordance with Snow Engineering Service Letter No. 134.
Compliance with Requirement 2 is terminating action for the inspections introduced by Requirement 1 above.
Note 2: FAA AD 96-15-02 also refers.
Compliance: 1. Unless previously accomplished, initially no later than 300 hours time in service since new or within 10 hours time in service, whichever occurs last, and thereafter at intervals not exceeding 150 hours time in service since last inspection, or at each occasion a cylinder is removed, whichever occurs first.
2. At the next occasion the crankshaft is removed from the engine. This amendment becomes effective on 21 May 1998.
Background: Cracks have been found in the crankshaft counterweights. In at least one instance a counterweight was liberated from the crankshaft resulting in an engine failure.
This amendment provides additional information relative to engines affected by this Directive.
The original issue of this airworthiness directive became effective on 10 October 1996.
Overview
The Civil Aviation Regulations 1998, specifically PART 39 - 106, was enacted to ensure the safety and airworthiness of aircraft operating in Australia, addressing potential risks associated with the maintenance and operation of aircraft engines. This legislative instrument was developed by the Civil Aviation Safety Authority to provide specific directives for maintaining engine airworthiness, thereby protecting public safety and ensuring compliance with international aviation safety standards. The problem this legislation aims to address is the occurrence of cracks in crankshaft counterweights, which can lead to engine failure, as evidenced by previous incidents. This directive, AD/PW-P/18 Amendment 1, targets Pratt and Whitney R1340 engines with specific crankshafts installed since 1991, requiring regular inspections and maintenance to mitigate the risk of engine failure due to counterweight defects. Compliance with these directives is mandatory to maintain the safety and reliability of these engines in Australian aviation.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 106, govern the airworthiness directives issued by the Civil Aviation Safety Authority (CASA) to ensure the safety of aviation operations. Under this regulatory framework, Pratt and Whitney R1340 engines that incorporate an Air Tractor, Inc. PMA crankshaft, P/No 90114, are subject to the AD/PW-P/18 Amendment 1R1340 PMA Crankshaft directive. This applies to engines that have had their crankshafts replaced with the specified PMA shaft since 12 September 1991. The directive mandates inspections and rework of the crankshaft counterweights as per specified engineering service letters to address instances where cracks have been found in the counterweights, leading to engine failure. Compliance requires inspections to be carried out initially no later than 300 hours of time in service since new or within 10 hours of time in service, whichever is later, and subsequently at intervals not exceeding 150 hours since the last inspection or at each occasion a cylinder is removed, whichever occurs first. This directive underscores the stringent safety measures enforced by CASA to mitigate risks associated with engine failures in civil aviation.
Key Provisions
The key operative sections of the Civil Aviation Regulations 1998, specifically Part 39 - 106, concern the Pratt and Whitney Piston Engines and mandate specific actions to ensure the airworthiness of these engines. Under Section AD/PW-P/18Amdt 1R1340, the directive applies to Pratt and Whitney R1340 engines that have had the crankshaft replaced with a PMA shaft, P/No 90114, since 12 September 1991. The directive requires two main actions: the inspection of the crankshaft counterweights in accordance with Snow Engineering Service Letter No. 135, and the reworking of these counterweights in line with Snow Engineering Service Letter No. 134. The reworking of the counterweights is considered a terminating action for the initial inspections.
The obligations imposed by this legislation on the parties governed are stringent and aim to ensure the safety of the aircraft operations. Owners and operators of Pratt and Whitney R1340 engines with the specified crankshaft must comply with the outlined inspection and rework requirements. The inspections must be conducted at specific intervals: initially no later than 300 hours since the engine was new or within 10 hours since service, whichever comes later, and thereafter at intervals not exceeding 150 hours since the last inspection, or at each occasion a cylinder is removed, whichever occurs first. Additionally, a further inspection is mandated at the next instance the crankshaft is removed from the engine.
Failure to comply with the requirements of this airworthiness directive can result in significant consequences. The Civil Aviation Safety Authority (CASA) may impose penalties for non-compliance, which could include enforcement actions or other regulatory measures. Although the specific penalties are not detailed in the text, it is understood that non-compliance could lead to severe repercussions given the critical nature of engine safety. Ensuring adherence to these directives is paramount to prevent potential engine failures, which could have catastrophic consequences for aviation safety.