It could be a case of racial profiling - or doing math in the wrong place at the wrong time. A noted economics professor was questioned by security after a fellow passenger reported that he was suspicious, scribbling intently on a notepad in what appeared to be cryptic code.
The pilot quickly determined that "the female passenger's concerns are not valid," American Airlines spokesman Casey Norton told AFP on Sunday.
According to media reports, Guido Menzio - an Italian with olive skin and dark curly hair - was travelling to give a talk when the woman next to him on the American Eagle flight from Philadelphia to Syracuse told the crew she was ill.