The US Defense Security Cooperation Agency has notified the Congress of a request from the Republic of Korea for a pair of helicopter fleet purchases through the Foreign Military Sales (FMS) program. The South Korean government is seeking to purchase 36 Boeing AH-64D Apache Longbow (Block III) and 36 Bell AH-1Z Cobra helicopters. The estimated cost for the sales is $3.6 billion for the Apache and $2.6 billion for the Cobra. Both transactions would include equipment, logistical supports, parts and training, with the Apache agreement providing 84 T-700-GE701D engines and the Cobra order including 84 T-700 GE 401C engines. The Apaches are intended for border security, counter-terrorism and counter-piracy missions. The Cobra fleet would fly aerial escort, armed reconnaissance, close air support and forward air control missions.