Space Shuttle Discovery was operational from its maiden flight on August 30, 1984, until its final landing on March 9, 2011. The spacecraft takes its name from four British ships of exploration named Discovery, primarily HMS Discovery, one of the ships commanded by Captain James Cook during his third and final major voyage from 1776 to 1779. Prior to its retirement, Discovery was NASA's Orbiter Fleet leader, having flown 39 successful missions in over 27 years of service. The Space Shuttle orbiter was a reusable winged "space-plane", a mixture of rockets, spacecraft, and aircraft. This space-plane could carry crews and payloads into low Earth orbit, perform on-orbit operations, then re-enter the atmosphere and land as a glider, returning its crew and any on-board payload to the Earth. The Space Shuttle Orbiter resembled an aircraft in its design, and was roughly the same size as a McDonnell Douglas DC-9 airliner.