Northrop Grumman Corp. [NOC] completed the initial step toward the critical design review (CDR) for the National Polar-orbiting Operational Environmental Satellite System (NPOESS), a company official said.
The CDR program milestone is expected to be completed in August, when the last action items are closed out.
NPOESS is run by NASA, NOAA and the Department of Defense.
Officials from those agencies, Northrop and independent auditors reviewed the NPOESS system-level design in relation to performance requirements, interfaces to external systems and the concept of operations.
NPOESS consists of four major segments, including the space, command-control-and-communications, and integrated data processing and field terminal segments.
The program, overcoming earlier difficulties that led to some expected sensors being removed from the satellite system, is making advances, such as an NPOESS sensor heading into thermal vacuum chamber testing.
The Visible Infrared Imager Radiometer Suite (VIIRS) flight unit is being subjected to the extreme hot and cold cycles typical of the space environment to determine its flight worthiness. Thermal vacuum testing will be conducted over nearly 100 days to ensure the sensor will operate in space as designed. Raytheon Co. [RTN], the subcontractor to Northrop, is conducting the VIIRS testing.
In years past, NPOESS has struggled with rising costs and schedule delays, and some sensors being omitted from the system. In congressional hearings, some lawmakers have expressed concerns that removal of sensors could leave gaps in U.S. data on crucial environmental/climate issues, as existing satellites reach end-of-life. But the NPOESS program since has rallied, with some lost ground regained, such as the full Ozone Mapping and Profiler Suite (OMPS) being restored to NPOESS, so it can trace harm to the ozone layer caused by chlorofluorocarbons.
In an interview, Bob Burke, Northrop vice president with advanced mission programs, said that NPOESS today is achieving a far greater level of success. While the company has “struggled with the sensors” issue, he said, “we have worked around the issue,” and made advances to improve the satellite system.
Further, the proposed Obama administration budget for the fiscal year ending Sept. 30, 2010, supports the NPOESS program, he said.
“We’ve got a plan against [the 2010 budget] that meets the replan,” meaning the restructured NPOESS program, Burke said. Thus he is “comfortable with the funding layout.”