to congressional headquarters on Aviation and Runway Safety declared that it is not possible to make sufficient headway with the runway safety concerns "until the human factors issues involving fatigue are addressed." The Union believes that the fatigue is the result of the decreased number of air traffic controllers, caused by the FAA's unilaterally enforced policies. They then defer this concern to the National Transportation Safety Board (NTSB), saying, "Air controller fatigue…continues to be a matter of concern for the NTSB." As it is a safety concern, the NTSB did release a safety recommendation to both the FAA and the NATCA. The issued recommendation analyzed four controller faulted runway "incursions" where, after investigation, the respective air traffic controller showed signs of fatigue. The report said, "Fatigue is known to degrade performance on cognitive tasks involving working memory and vigilance", and that the mistakes made by the controllers in the investigated instances were consistent with signs of fatigue. The board attributed this fact to both the shift-work used at most facilities which often does not allow sufficient rest time between shifts, and to the increase amount of overtime worked due to the decrease in controllers. References External links NATCA official website http://eightiesclub.tripod.com/id296.htm (PATCO strike of 1981) http://www.heritage.org/Research/Reports/2006/05/Winning-the-Fight-to-Curb-Excessive-FAA-Salary-Costs (FAA/NATCA pay and contract history) https://web.archive.org/web/20110723215642/http://lan.natca.net/2009CBA.pdf (Red Book - Current Contract between FAA and NATCA) https://www.faa.gov/regulations_policies/orders_notices/index.cfm/go/document.information/documentID/1036234 (JO 7110.65Y Air Traffic Control) https://www.faa.gov/regulations_policies/orders_notices/index.cfm/go/document.information/documentID/1028512 (JO 3120.4P Technical Training Order) AFL–CIO Air traffic control in the United States Organizations based in Washington, D.C. Trade unions established in 1987 Air traffic controllers' trade unions