Those were the same concerns that were cited when the FAA first grounded and then released crop dusters for flying in the week following the attacks on the World Trade Center and the Pentagon.

According to published reports, unidentified U.S. government sources said a manual for operation of crop-dusting equipment had been found among the belongings of Zacarias Moussaoui, an Algerian who was arrested in August for immigration violations. The Miami Herald and Washington Post also reported Monday that suspected hijacker Mohamed Atta visited, at least twice, a small airport in South Florida to inquire about the capabilities of a crop-duster plane. “(Atta) wanted to know how to fly it, how to crank it, how much it would haul,” James Lester, 50, told the Herald about Atta’s visits to a small airstrip in Belle Glade, Fla. Both newspapers said Atta was accompanied by several groups of men and visited the airport as recently as last month.