The Lockheed C-130 Hercules is a four-engine turboprop military transport aircraft built by Lockheed and used by many countries, primarily the United States. The C-130 has been in continuous service with the United States Air Force. Capable of using unprepared runways for takeoffs and landings, the C-130 was originally designed as a troop, medical evacoution, and cargo transport aircraft. The versatile airframe has found uses in a variety of other roles, including as a Gunship (the AC-130 ), for airborne assault, search and destroy, scientific research support, weather reconnaissance, aerial refueling, maritime patrol and aerial firefighting. It is the main Tactical lifter for many military forces worldwide. Over 40 models and variants of the Hercules serve with more than 50 nations.