July 13, 2018

Follow-up: Variable Pitch Propellers Overhaul Exemption


Numerous COPA members have been anxiously awaiting a TCCA decision with respect to our request to grant private owners of privately used small aircraft an exemption to the mandated 10-year variable pitch propeller overhaul. COPA submitted the request for exemption in November 2017, TCCA completed their assessment in March 2018, COPA and TCCA met in April to discuss the result of this assessment. At first glance, TCCA does not support COPA’s initial request for exemption.

Mr Jeff Phipps, Chief, Operational Airworthiness, Standards Branch, participated in the COPA convention in Saint John, NB, delivering a presentation on aircraft maintenance requirements on June 22. Mr Phipps addressed the specific issue of our request. He cited two main reasons for not supporting our request for exemption for now: lack of data and conflict with current Instruction for Continued Airworthiness (ICA) recommendations that come from the manufacturer. ICA recommendations are precisely that: recommendations. These recommendations are typically used to provide guidance in the development of aircraft maintenance requirements and programs. COPA recognizes that the airworthiness authorities often mandate these recommendations, but not necessarily in all cases. These same authorities will occasionally review the criteria of ICA recommendations and may from time to time support a more flexible approach.

With respect to lack of data, COPA has a different perception. Ours reflects the FAA’s approach. The US General Aviation (GA) fleet of privately utilized aircraft numbers are well beyond the equivalent Canadian fleet. The US annual flying hours for GA on variable pitch propellers are far in excess of those in Canada yet the US do not have a mandated 10-year variable pitch propeller overhaul. COPA’s investigation indicates that the US GA fleet does not exhibit problems related to variable pitch propeller failures. Through our investigation in preparing our submittal to TCCA, we know there are currently no statistics or data relevant to variable pitch propeller failures of significant value within the context of this discussion. In fact, aviation insurance companies such as AIG for instance, one of the most important aviation insurers, cannot provide specific statistics on this due to the lack of insurance claims concerning aircraft accidents resulting from variable pitch propeller failures as these do not occur enough to generate meaningful statistics. Considering that aircraft and aircraft components used in Canada originate almost exclusively from the US, COPA believes it would be appropriate to consider the US experience as a suitable source of reliable data. At this conjecture, COPA is wondering what approach TCCA will use to collect any relevant data if any, and how long this will take. COPA has offered to help on getting some data from our members. 

Mr Phipps, in his presentation, also identified some future steps. TCCA will look at options other than an overhaul, the possibility of developing an internal inspection task (hopefully not requiring dismantlement of the propeller) that could result in either continued monitoring or overhauling depending on findings, and further exploratory discussions on other options. They are looking to present something to us by the end of this year. COPA wishes to reassure its membership that we will keep TCCA to their commitments and continue our discussions with them in finding a safe and less financially cumbersome solution than an unwarranted prop overhaul.