Photo of United Boeing Model 727
Photo of United Boeing Model 727
Accident Perspectives:
Airplane Life Cycle
  • Operational
  • Design / Manufacturing
Accident Threat CategoriesGroupings
  • Flight Deck Layout / Avionics Confusion
  • Lack of System Isolation / Segregation
  • Automation
Accident Common Themes
  • Human Error
  • Flawed Assumptions
  • Unintended Effects

United Airlines Flight 266, Boeing Model 727-22C, N7434U

Location: Los Angeles, California

Date: January 18, 1969


On January 18, 1969, United Airlines Flight 266, a Boeing Model 727-22C series airplane, crashed into Santa Monica Bay shortly after takeoff from Los Angeles International Airport (LAX). The takeoff occurred at night in light rain and fog. The airplane was dispatched with the No. 3 generator inoperative per the minimum equipment list (MEL). Shortly after takeoff, the flightcrew reported a fire warning in the No. 1 engine, and subsequently shut down that engine, resulting in the loss of the No. 1 generator. Shortly thereafter, the No. 2 generator failed, resulting in a total loss of generated electrical power. The standby electrical system failed, or did not activate, leaving the airplane with no electrical power, and with all instruments unlit, and unreadable. The National Transportation Safety Board (NTSB) determined that the most probable cause of the accident was flightcrew disorientation during a night, instrument departure in which the instrument displays were disabled due to a complete loss of electrical power. The NTSB was unable to determine why all generator power was lost and why the standby electrical system was either not activated or failed to function.