Friday, February 01, 2008

FAA History Lesson -- February 1

From the FAA Historical Chronology, 1926-1996...

”Feb 1, 1991: In a night approach to Los Angeles International Airport, a USAir 737 landed atop a Sky West commuter Fairchild Metroliner III. Both planes then slid into a building as fire began. Fatalities included all 12 persons aboard the commuter flight and 22 of the 89 aboard the USAir flight. On Oct 22, the National Transportation Safety Board listed the accident's probable cause as air traffic control management deficiencies that lead to a controller's issuing inappropriate clearances. FAA actions after the accident included assigning additional controllers to the tower and adjusting runway lights to prevent glare from obstructing the view from the tower. (See Feb 7, 1991.) “

Lest my readers forget (and someone always does), I was a Center controller. I worked enroute traffic on a radar scope. The airspace I worked was north and west of Charlotte, NC and I worked it from a building located south of Atlanta, GA. In other words, I wasn’t in a Tower and I never worked in a building with a window.

This accident happened at Los Angeles International (LAX) and the flights were being worked by the controllers in the Tower. Despite the differences in our respective jobs as controllers, I am struck by the similarities. As evidenced by the name of this blog, I place a tremendous amount of emphasis on having the flick -- being able to see aircraft in your mind as well as with your eyes. It is a very rare -- yet critical -- skill. And it is as delicate as a piece of film running through a movie projector.

The following is from the National Transportation Safety Board’s report on this accident.

”The Safety Board believes that there is no existing automated monitoring system on which a tower can rely to ensure that human performance errors will always be detected. Unlike radar controllers, who have conflict and minimum safe altitude alerting, or most air carrier flightcrews, who have ground proximity and traffic conflict alerting, local and ground controllers must rely almost totally on their eyes, ears and memory to perform their duties. The expectation that controllers can perform for any length of time without error is unwarranted. In addition, the FAA’s expectation of flawless human performance is unrealistic in rapidly changing and dynamic environments that exist at airports such as LAX. Therefore, the Safety Board believes that any job aids and procedures, such as strip marking and flight strip forwarding, which are designed to improve each tower controller’s performance, should be adopted and emphasized, repeatedly, until other independent, automated systems become available. The Safety Board also believe that procedural redundancy through the use of tower cab coordinators, local assist controller and ground control assistants, who can provide a “second set of eyes and ears” should be utilized to the maximum extent possible, especially when traffic conditions warrant that such an additional position be manned.

In the aftermath of the accident at the Atlanta Hartsfield International Airport, involving a B-727 and a Beech King Air that collided on the runway, the Safety Board concluded that the cause of the accident was, “the failure of the FAA to provide air traffic control procedures that adequately take into account those occasional lapses in performance that must be expected.” The Safety Board believes that the circumstances of the Los Angeles runway incursion underscore the need to recognize, acknowledge, and take into account those lapses in performance. The designers and operators of complex systems, such as the ATC system, who fail to fully implement required design features and operating procedures, and who allow a single individual to assume the full burden for safety-critical operations, must share responsibility for occasional human performance errors. The Safety Board believe that the FAA adherence to the National OPS would have provided the redundancy that could have prevented this accident.

(Author’s note: For some reason, I couldn’t “copy and paste” from that report. So, I had to type all of that excerpt in. “...expectation of flawless human performance is unrealistic.” And in that I don’t have an editor and it’s 5:30 AM, I don’t have a “second set of eyes and ears” to check it. It’s a good thing your life doesn’t depend on it.)

You can review the Atlanta accident referenced above here.

Don Brown
February 1, 2008

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