Alaska Airlines Flight Human Factors

Alaska Airlines Flight Human Factors The term human factors can be defined as anything to do with humans. In aviation maintenance human conditions like stress, illness, complacency are important because if these factors are not taken care of can lead to fatal accidents. Human factors in aviation industry have become more significant as over the time it has been realized that in most airborne accidents, human error is the main reason rather than mechanical failure. Human Factors are too broad a definition for our understanding of its application in aircraft maintenance. It focuses on a wide range of challenges faced by any human in his/her day to day personal or professional life and when combined how they can lead to human errors and ultimately to a fatal accident. This report is the case study of one such incident, Alaska Airlines Flight 261, a McDonnell Douglas MD 83, which crashed into Pacific Ocean near Anacapa Island, California killing all 88 people on board. The National Transportation Safety Board (NTSB) determ ines that the probable cause of this accident was a loss of airplane pitch control resulting from the in-flight failure of the horizontal stabilizer trim system jackscrew assembly’s acme nut threads. The thread failure was caused by excessive wear resulting from Alaska Airline’s insufficient lubrication of the jackscrew assembly (NTSB (2003). Loss of Control and Impact with Pacific Ocean Alaska Airlines Flight 261. WASHINDTON, DC: NTSB. 180.) After going through the accident and studying all the possible causes of this fatal accident it has been observed that it was the chain of events that led to one error after the other. The Cheese Error Model is used for analysis to explain the causes. C:UsersYashikaDesktopswisscheese2.gif Fig 1 (http://www.aviation.unsw.edu.au/about/articles/swisscheese.html) SYNOPSIS According to NTSB report 2003, â€Å"on January 31, 2000, about 1621 Pacific standard time, Alaska Airlines flight 261, a McDonnell Douglas MD-83, N963AS, crashed i nto the Pacific Ocean about 2.7 miles north of Anacapa Island, California. The 2 pilots, 3 cabin crewmembers, and 83 passengers on board were killed, and the airplane was destroyed by impact forces. Flight 261 was operating as a scheduled international passenger flight under the provisions of 14 Code of Federal Regulations Part 121 from Lic Gustavo Diaz Ordaz International Airport, Puerto Vallarta, Mexico, to Seattle-Tacoma International Airport, Seattle, Washington, with an intermediate stop planned at San Francisco International Airport, San Francisco, California. Visual meteorological conditions prevailed for the flight, which operated on an instrument flight rules flight plan.† (NTSB. (2003). HISTORY OF FLIGHT. In: NTSB Loss of Control and Impact with Pacific Ocean, Alaska Airlines Flight 261. WASHINDTON, DC: NTSB. 1.) PROBABLE CAUSE The National Transportation Safety Board carried out an intense investigation to find out what brought the flight 261 down and founded many r easons responsible for this accident. The NTSB report considered the main reason as the loss of airplane pitch control due to the in-flight failure of the horizontal stabilizer trim system jackscrew assembly’s acme nut threads. The thread failed because of excessive wear resulting from Alaska Airlines insufficient lubrication of the jackscrew assembly. NTSB reports also mentions about the design flaw of McDonnell Douglas MD-80 as it didn’t have fail safe mechanism to prevent the disastrous effects of failure of acme nut threads.