Lessons Learned in Maintaining Aircraft in ETOPS Operations

United Airlines has been operating long range, two-engined aircraft in ETOPS (Extended Range Operation with Two Engine Airplanes) for almost nine years. During that time, the shared industry experience and in-service operating results have created changes in the maintenance program and plan, and led to policies which have altered fleet operations. With an emphasis on safety-of-operations, this paper identifies lessons learned from experience and it also documents the adjustments to the maintenance program and policies.