The Pentagon's Doomsday plane's mission is to act as the country's military command center in case the ground-based ones are ...

United Airlines Flight 863 took off from San Francisco like any routine flight—but within seconds, the Boeing 747-400 was in serious trouble. Climbing too slowly, struggling to gain altitude ...

The Boeing 777 was the long-range, relatively high-capacity aircraft United needed to service destinations that were impractical for the 767 and 747. The 777-300ER replaced its Boeing 747-400s.

Both planes involved were Boeing 777s. One of the planes, UA877, bound for Hong Kong, had 306 passengers and 16 crew aboard. The other one, UA863, bound for Sydney, had 202 passengers and 16 crew.

The 747 has generally been used for international flights. The last United Airlines international flight for the 747 was on October 29, from Seoul, South Korea, to San Francisco.