Designed in 1951 for the US Air Force Tactical Air Command to meet a requirement for a transport able to airdrop troops at 125 knots (144 MPH), the C-130 Hercules was built by Lockheed, and the YC-130A first flew on August 21, 1954. Deliveries of the first 219 aircraft began in December 1956, and the C-130B replaced the A model's three-blade turboprop engines with stronger four-blade turboprop engines, with deliveries beginning in May 1959. The C-130E used the same engines but added two external 1,290 gallon fuel tanks and increased maximum takeoff weight, and deliveries of the first E models began in August 1962. Since then, more than fifty variants have been built, including the C-130J, first purchased in February 1999. One of the most recognizable transport aircraft in the world, the aircraft's more than fifty years of operation reflects its versatile design. Beyond traditional airlift, aeromedical, and humanitarian missions, specialized versions have served as gunships and in Antarctica resupply, weather reconnaissance, aerial refueling, and firefighting. The featured C-130E is painted in Air Mobility Command "Proud Gray" as it would have appeared while assigned to Little Rock AFB, Arkansas, in the 1990s. First acquired by the Air Force on August 1, 1963, this aircraft served in England, France, Germany, Taiwan, Thailand, and Vietnam. For approximately twenty years beginning in September 1974, it was flown by the 146th Airlift Wing, California Air National Guard, and supported firefighting efforts throughout the western United States.