Covers Aircraft With Air Comm Corporation’s Supplemental Type Certificate SH2750NM Installed

The FAA has been notified of a potential issue with certain Bell Helicopter Textron Canada Limited (BHTCL) Model 206L-1, 206L-3 and 206L-4 helicopters with Air Comm Corporation’s Supplemental Type Certificate SH2750NM installed.

According to the agency, a number instances of the air conditioner pulley’s locking system (AC Pulley’s Drive Ring), which is installed on the Oil Cooler Drive Shaft’s splined quill, causing excessive spline tooth wear to itself and to the respective mating splines on the quill. The reported damage does not affect the tail rotor drive shaft’s Thomas coupling or the couplings connection to the Oil Cooler Drive Shaft.

At this time, the airworthiness concern is not determined to be an unsafe condition that would warrant airworthiness directive (AD) action, but the agency has issued a Special Airworthiness Information Bulletin (SAIB) related to the issue.

The FAA recommends that all owners, operators, and maintenance personnel of the affected aircraft listed in the introduction of this SAIB adhere to inspection and time of accomplishment instructions of Air Comm Service Bulletin SB206EC-18-07, Rev A or later revision “Bell 206 Air Conditioner Spline Inspection”. The FAA further recommends that the Air Conditioner pulley’s lock ring be routinely inspected when normal routine maintenance per Bell Helicopter maintenance requirements allows access.

(Image provided with SAIB)

FMI: SAIB