WASHINGTON — Launch of the first next-generation U.S. civil polar-orbiting weather satellite has been pushed back two days after preliftoff tests revealed leaky components in the Delta 2 rocket that will loft the satellite.
The National Polar-orbiting Operational Environmental Satellite System Preparatory Project (NPP) now is scheduled to launch Oct. 27 from Vandenberg Air Force Base, Calif. The launch window is 2:48 a.m. to 2:57 a.m. local time, NASA and launch provider United Launch Alliance (ULA) said in brief online notes posted Oct. 4.
Two components, a cracked hydraulic tube and a flexible connection between two exhaust ducts on the rocket, were to blame for the leaks, NASA said in an Oct. 4 statement. The cracked tube has been replaced. The damaged duct connection “is being removed and replaced,” NASA said in the statement.
NPP was conceived as an instrument test bed for the now-canceled National Polar-orbiting Operational Environmental Satellite System, a civil-military project involving NASA, the National Oceanic and Atmospheric Administration (NOAA) and the Department of Defense. NPP was elevated to an operational role following delays to that program, which was canceled in 2010.
NOAA will use the NPP satellite for operational weather forecasting; NASA will use the data for climate monitoring.
NPP is the final payload scheduled to be launched by the Delta 2, but ULA has five of the vehicles remaining in inventory. NASA on Sept. 30 added the Delta 2 to its NASA Launch Services 2 contract, making the vehicle available to launch agency payloads.