FAA Issues Safety Alert for Improper Overhaul of Some McCauley Propellers

The FAA last week warned aircraft operators of potential problems if they had their McCauley constant speed propellers serviced by Sensenich Propeller Services, Inc., North Windham, Connecticut. The agency says the company was re-installing equipment without fully following the recommended methods, techniques, and practices prescribed in the current McCauley constant speed propellers maintenance manual. The agency said the safety alert – SAFO 19002 – applies to all propellers serviced by the Connecticut company that previously held FAA Air Agency Certificate No. Q0PR011X for an overhaul of propeller assemblies. The online link to the Windham Connecticut facility was no longer listed on the Sensenich website, nor was the company's website operating.

An FAA investigation found this maintenance provider claimed to be completing overhauls, but failed to test or replace various replacement parts, as required per the McCauley constant speed propellers overhaul manuals. In particular, the propeller return springs were not tested or replaced on all 47 McCauley constant speed propellers involved. Additionally, the following items were not replaced on some of the above-mentioned propellers: blade-actuating links, actuating link bearing, ball bearings, ball bearing separators, cylinder assembly cover screws, blade retaining rings, propeller to engine mount studs, and one fill plug.

Since the improper maintenance referenced here occurred during overhaul-level maintenance, owners and operators that may have had propellers overhauled by Sensenich Propeller Service Inc. should have affected propellers inspected by an appropriately rated repair station to determine if those propellers meet the manufacturer’s recommended continued airworthiness requirements.

The FAA says the actions recommended in this SAFO may be accomplished with three distinct steps.

Inspect aircraft records, propeller records, FAA Form 8130-3 airworthiness approval tags, and aircraft parts inventories for any McCauley constant speed propellers approved for return to service by Sensenich Propeller Service, Inc.

Quarantine and inspect McCauley constant speed propellers not installed. Maintenance providers should ensure any affected propellers in their inventory referenced by this SAFO meet the manufacturers recommended continued airworthiness requirements for overhaul. This may necessitate a thorough maintenance records check and/or making an airworthiness determination to ensure the propeller meets the manufacturer’s recommended overhaul requirements.

Inspect propellers currently in use for affected McCauley constant speed propellers currently installed, owners/operators should have the suspect propellers inspected. Owners/operators should also closely monitor the suspect propellers’ health using the original equipment manufacturer recommendations or other approved maintenance program methods.