Incident Overview
During takeoff, air traffic controllers observed sparks emanating from the rear of the Boeing 717-200. Shortly thereafter, the pilot reported a problem with the right main landing gear and gear door, with the landing gear in the retracted position. The airplane circled for approximately one and a half hours to burn fuel, after which the captain performed an uneventful landing.
Investigation Findings
Post-flight examination of the airplane revealed that the number 4 wheel bearing had failed. The wheel race became welded to the axle, and as the wheel continued to rotate, the remaining races and bearings fragmented and separated from the wheel. Examination of the remaining three wheel hubs disclosed the presence of water.
Previous Occurrence and Manufacturer Response
A similar incident had occurred approximately 10 months prior involving another Boeing 717-200. In that case, due to the catastrophic damage to the tire and bearings, it could not be determined whether water was present. As a result of the second incident, the manufacturer incorporated a hubcap gasket designed to prevent moisture from becoming trapped in the wheels.