File Photo: A Helicopter Crewman Stands Beside An Ah-64A Apache Helicopter As It Is Prepared For Takeoff During Operation Desert Shield January 23, 1991. The Helicopter Is Armed With An M-230A1 30Mm Automatic Cannon Beneath Its Cockpit And Is Carrying Agm-114 Hellfire Missiles On Its Wing Pylon. . U.S. Defense Secretary William Cohen Said On April 5, 1999 That Plans To Send 24 Tank-Hitting Apache Helicopters Into Yugoslavia Were Not A Prelude To Deploying Ground Troops To Defeat Serb Forces. The Low-Flying Apache Helicopters Are More Vulnerable To Anti-Aircraft Fire And Cohen Conceded That They Posed A Higher Risk For U.S. Troops Than The Current Air Campaign, But That This Was "Part Of The Equation."  (Photo By U.S. Army/Getty Images)