Allison Engine says that a badly manufactured bearing was to blame for the in-flight shutdowns of AE3007 turbofans powering the Embraer RJ-145. The plan is to have completed a retrofit across the in-service fleet by April.
"The bearings for this engine are made by several manufacturers and one particular supplier of one bearing had a problem," says Allison large commercial engines director, Al Novick. The problem occurred in the number four bearing when the surface began to corrode. The powder combined with lubricating oil to produce a metallic paste, which clogged the oil supply and resulted in a low pressure warning. The engine was then manually shut down by the crew.
Production standard bearings are being retrofitted to the portion of the fleet affected by the quality problem. A service bulletin has been issued to operators instructing them to increase inspections of the magnetic plug which detects the presence of paste.
Allison is refurbishing the original flight test engines used on the ERJ-145 for use on the shortened ERJ-135 test programme.
Source: Flight International
