The McDonnell Douglas (now Boeing) F15 Eagle is a twinengine, allweather tactical fighter designed to gain and maintain air superiority in aerial combat. It was developed for the United States Air Force, and first flew in July 1972. It is one of the most recognized fighters of the modern day. The F15E Strike Eagle derivative is an allweather strike fighter that entered service in 1989. The U.S Air Force plans to keep the F15 in service until 2025.