Bell helicopters must replace a specific valve that keeps cracking

The US aviation regulator proposes a new rule for certain Bell 427 helicopters. It would require inspecting and replacing a specific transmission oil check valve if it shows cracks or leaks.

This is a routine safety update. The Federal Aviation Administration regularly issues these directives when a specific part on an aircraft model shows a defect. It means operators of these helicopters will have to spend money to replace the part, but it prevents potential failures.