While diverted attention and the loss of situational awareness can result in errors in identifying one's location, they can also result in errors in executing normal procedures and tasks. Despite the engineer's experience in the area, after operating around the 65 mph curve near MP 83.5, he failed to execute his next significant operating task: decelerating the train as it approached the curve at Frankford Junction, a maneuver he had performed many times. Omitting normal procedural steps is a form of prospective memory error (Dismukes, 2006). Prospective memory refers to remembering to perform an intended action at some future time or, more simply, remembering to remember.[1] It typically focuses on when to do something. Failures of prospective memory typically occur when we form an intention to do something later, become engaged with other tasks, and forget the thing we originally intended to do.[2] It is possible, then, that the Amtrak engineer failed to slow his train for the upcoming curve because his attention to the radio communications about the SEPTA train emergency caused him to forget about the impending operation.
The NTSB has investigated accidents where competing information interfered with a crewmember's retention of vital information, which affected the crewmember's future actions. For example, in the 1996 collision between MARC and Amtrak trains in Silver Spring, Maryland, the NTSB determined that the MARC train engineer apparently forgot the most recent signal he had passed and ran his train through the next signal because he was focused on other tasks and information.[3] The engineer was processing competing information that included the mental and physical tasks required to stop the train at an upcoming station; carrying on radio conversations with an engineer on another train; monitoring defect detector broadcasts and disrupted radio broadcasts; and listening to or talking with another crewmember in the cab. Processing these multiple pieces of information interfered with his retention of the signal information.
In addition to this accident, the NTSB has investigated other accidents where experienced crewmembers forgot to complete a normal procedural step they had successfully performed many times on previous trips. In the 2005 derailment of a Norfolk Southern Railway freight train in Graniteville, South Carolina, the train crew failed to restore a switch to the normal main track position, a task they had routinely performed before the accident. [4]In a number of aviation accidents, experienced crews forgot to perform routine duties such as setting flaps and slats to takeoff position; setting hydraulic boost pumps to high position before landing; and arming the spoilers before landing.[5] In many of these accidents, the crewmembers' routine duties were
- ↑ An example of prospective memory is remembering to take medicine at night before going to bed or remembering to deliver a message to a friend.
- ↑ Prospective memory depends on several cognitive processes, including planning, attention, and task management.
- ↑ National Transportation Safety Board, Collision and Derailment of Maryland Rail Commuter MARC Train 286 and National Railroad Passenger Corporation AMTRAK Train 29, Silver Spring, Maryland, February 16, 1996, Railroad Accident Report RAR-97/02 (Washington, DC: NTSB, 2002).
- ↑ National Transportation Safety Board, Collision of Norfolk Southern Freight Train 192 with Standing Norfolk Southern Local Train P22 With Subsequent Hazardous Materials Release, Graniteville, South Carolina, January 6, 2005, Railroad Accident Report RAR-05/04 (Washington, DC: NTSB, 2004).
- ↑ (1) National Transportation Safety Board, Northwest Airlines, McDonnell Douglas DC-9-82, N312RC, Detroit Metropolitan Wayne Country Airport, Romulus, Michigan, August 16, 1987, Aircraft Accident Report AAR-88/05 (Washington, DC: NTSB, 1988). (2) National Transportation Safety Board, Runway Overrun During
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