The DC-8, also known as the Douglas DC-8 or McDonald Douglas DC-8, is a four engine large jet airliner developed by Douglas Corporation in the United States. It was designed in June 1955 and began production in 1958. DC-8 ceased production in 1972 and was replaced by a larger DC-10. Most of the only DC-8 currently available have been converted to cargo planes.DC-8 was the biggest competitor of Boeing 707 in the 1950s. Since the cargo volume of DC-8 is slightly more than that of Boeing 707, there are still very few DC-8 after engine replacement used in some third world countries, while DC-8 and B707 in most countries announced their flight suspension around 2000 due to high fuel consumption and heavy pollution.