The Boeing 767-300ER (Extended Range) is known for being one of the most reliable aircraft in its class. The Boeing 767 bridged the gap between older widebody aircraft like the McDonnell Douglas DC-10 and Lockheed L-1011 and the later twinjet widebodies like the A330 and Boeing 777. In the end, it was the development of the clean-sheet Boeing 787 Dreamliner with its more advanced engines, extensive use of lightweight composites, and other innovations like large windows that doomed it.