There was a crash some years ago when a commercial airliner had some fairly minor malfunction (I think it was a landing gear down and locked light not lit) at night. They got so engrossed in troubleshooting that damn lightbulb that they allowed the plane to fly into the swamp. No survivors. The voice recorder had them yakking about that light until impact.
EAL411, the last Enroute Controller to talk to them was one of my ATC Instructors....
