Bombardier CRJ200 operators are being urged to inspect emergency manual landing gear release systems to ensure they are operating correctly, following an in-service report of a latent failure potentially caused by unrelated maintenance.

A Transport Canada (TC) Safety Alert explains that the combination of “a rapid or inadvertent release of the manual gear release handle” and a mis-rigged system component could cause the systems to jam. “The operator stated that the mis-rigged condition of the manual gear release system was due to the distortion of the cable turnbuckle located alongside the lower floor panel of the forward avionic bay,” the alert, issued last month, explains. The “distortion” most likely occurred when mechanics accessed the avionics bay through the floor panel, the regulator notes. The mis-rigging caused a cable to come off a pulley, which jammed the system.

Transport Canada recommends that CRJ200 operators inspect the systems in accordance with guidelines in the aircraft maintenance manual (AMM). 

“Bombardier engineering confirmed the required AMM inspections and functional tasks are well-defined for working the manual gear release system, where diligence by the operator/maintainer to accomplish the necessary inspections is required when work is done around the affected area and system,” the TC alert says.

The European Aviation Safety Agency pushed the alert out to CRJ operators in Europe earlier this week.