On April 23, 2005, Zacarias Moussaoui pled guilty to participating in the September 11 attacks on America . With Moussaoui?s guilty plea in the US Federal District Court in Alexandria, Virginia, the door to one chapter in the 9/11 conspiracy closes. But, many questions remain unanswered about Moussaoui and his role in the hijacking and some of the things he did while he was in the US leading up to his arrest on August 17, 2001. One question that needs to be examined in further detail is the interest that Moussaouri and other terrorists have shown in crop dusting. Could terrorist use crop dusters to attack targets in the United States? How hard would it be for a terrorist to learn how to take off and fly a loaded crop duster? Would a terrorist cell be able to acquire sufficient dangerous chemicals to execute an attack? Would a terrorist cell be able to reconfigure spraying nozzles and understand the meteorological conditions in order to deliver airborne chemical agents?

In June 2001, Moussaouri made inquiries about starting a crop dusting company. After Moussaoui?s arrest, law enforcement officials discovered that he had a computer disk, containing information related to the aerial application of pesticides. Moussaoui’s possession of a crop dusting manual is not the first time that al-Qaeda has shown an interest in crop dusters. Essam al Ridi, a naturalized US citizen, was a wintess at the trials of four men involved in the attacks on the US Embassies in Kenya and Tanzania and stated that Osama bin Laden wanted to purchase a crop dusting operation. Ridi, a pilot, purchased a used plane for bin Laden for $230,000 and transported the plane to Khartoum, Sudan . Mohammad Atta is also alleged to have inquired about crop dusters while he was preparing for the 9/11 attacks.