The U.S. Department of Defense has announced that Lockheed Martin Corp. received a $12.8 million domestic and Foreign Military Sales (United Kingdom) contract for refurbishment support services for the Apache attack helicopter.

According to a statement, work locations and funding will be determined with each order, with an estimated completion date of Aug. 31, 2020. U.S. Army Contracting Command, Rock Island Arsenal, Illinois, is the contracting activity.

The AH-64 Apache is the world’s most advanced multi-role combat helicopter and is used by the U.S. Army and a growing number of international defense forces.

The U.S. Army Apache fleet has accumulated (as of July 2016) more than 4.2 million flight hours since the first AH-64A was delivered to the U.S. Army in January 1984.