The Air Force received its first batch of three F-15K fighter jets from the U.S. aircraft giant Boeing on Wednesday under the second-phase F-X fighter acquisition program, officials said.

The high-end multi-role aircraft arrived at the 11th Fighter Wing based in Daegu in the morning. They departed from Saint Louis on Aug. 31 and received aerial refueling support from a KC-10 tanker of the U.S. Air Force while flying over the Pacific, officials said.

With the latest addition, the Air Force has a total of 42 F-15Ks. Under the first-phase program from 2002-2008, 40 F-15Ks were delivered, but one crashed in the waters off Pohang during a nighttime mission in June 2006.

Under the second-phase project signed in May 2008, the U.S. aircraft giant is scheduled to provide a total of 21 F-15Ks by March 2012.

The F-15K is capable of air-to-ground, air-to-air and air-to-sea missions day and night in any weather conditions. It can fly at a maximum speed of Mach 2.3 with an operational radius of 1,800 kilometers. A single aircraft costs about $100 million.

The model of F-15K received under the second-phase project is equipped with a PW-229 engine produced by Pratt & Whitney, whereas the model delivered under the first-phase program is equipped with a GE-129 engine manufactured by General Electric.

The use of a different engine is intended to prepare for a case in which one of the two types fails to work, officials explained.

By Song Sang-ho (sshluck@heraldcorp.com)