The Lockheed C-130 Hercules is a four-engine turboprop military transport aircraft designed and built originally by Lockheed, now Lockheed Martin. Capable of using unprepared runways for takeoffs and landings, the C-130 was originally designed as a troop, medical evacuation, and cargo transport aircraft. The versatile airframe has found uses in a variety of other roles, including as a gunship (AC-130), for airborne assault, search and rescue, scientific research support, weather reconnaissance, aerial refueling, maritime patrol, and aerial firefighting. It is now the main tactical airlifter for many military forces worldwide. Over 40 models and variants of the Hercules serve with more than 60 nations.The C-130 entered service with U.S. in the 1950s, followed by Australia and others. During its years of service, the Hercules family has participated in numerous military, civilian and humanitarian aid operations. The family has the longest continuous production run of any military aircraft in history. In 2007, the C-130 became the fifth aircraft—after the English Electric Canberra, Boeing B-52 Stratofortress, Tupolev Tu-95, and Boeing KC-135 Stratotanker, all designs with various forms of aviation gas turbine powerplants—to mark 50 years of continuous use with its original primary customer, in this case, the United States Air Force. The C-130 is one of the only military aircraft to remain in continuous production for over 50 years with its original customer, as the updated C-130J Super Hercules.