When the crew of United Airlines Flight 173 was making an approach to Portland International Airport on the evening of Dec 28, 1978, they experienced a landing gear abnormality. The captain decided to enter a holding pattern so they could troubleshoot the problem. The captain focused on the landing gear problem for an hour, ignoring repeated hints from the first officer and the flight engineer about their dwindling fuel supply, and only realized the situation when the engines began flaming out.