This Land Line article has comments from a researcher admitting that the outdated fatigue statistic is not accurate.
http://www.landlinemag.com/todays_news/Daily/2011/May11/050911/051111-01.shtml
This is a blog written by an OOIDA executive about the overused “31 percent” statistic http://www.ooida.com/blogI/?p=171
Partial testimony of Dr. Ronald Knipling, the report author quoted in Land Line Magazine about the incorrect fatigue stat, during the May 11 forum of the National Transportation Safety Board.
Visit this link and locate the forum archive from May 11. http://www.capitolconnection.net/capcon/ntsb/ntsb.htm#