VANDENBERG AIR FORCE BASE, Calif. (AP) – A powerful Delta 4 Heavy rocket carrying a US spy satellite took off on Saturday from California.
The rocket propelled the satellite of the National Reconnaissance Office of Vandenberg Air Base at 11:10 am Pacific time, arching over the Pacific Ocean west of Los Angeles toward space.
External rocket propellants separated about four minutes during flight, followed soon by separation of the first stage central booster and the successful upstairs ignition.
As is customary with rated payloads, the United Launch Alliance only launches takeoff until the aerodynamic fairing that covers the payload is discarded.
Details of the mission, dubbed NROL-71, were not disclosed.
The launch has been repeatedly postponed since the end of last year for several reasons, including hydrogen leakage, strong winds and problems with land-based communications equipment.
The National Reconnaissance Office is responsible for US intelligence satellites.
The United Launch Alliance is a joint venture between Lockheed Martin and Boeing.
The Delta 4 Heavy is 233 feet (71 meters) tall.