US weather satellite malfunctions for second time in less than a year, NOAA has notified Congress, disruption may compromise future satellites in the mission-Aviation Week

5/23/13, "Boeing-built Weather Satellite Goes Dark Over East Coast," aviationweek.com, Amy Butler

"The U.S. National Oceanic and Atmospheric Administration (NOAA) is activating an in-orbit Geostationary Operational Environmental Satellite (GOES) spare as experts try to rescue a primary spacecraft that has failed to deliver basic weather data for a second time in less than a year, according to officials in the satellite community..

The Boeing GOES-13, originally known as GOES-N, was launched in 2006. The first indication of a failure came at 11:38 p.m. EDT May 21, says George Jungbluth, a NOAA spokesman. GOES-13 failed to deliver its basic imagery and weather data, including imaging and sounding information. 

The satellite is now in a safe-hold mode, which allows operators to communicate with it in an attempt to diagnose and solve the problem. But it is no longer conducting its mission owing to attitude control problems, according to government officials.

NOAA, which operates the GOES system, has notified Congress of the problem. Communications officials at Boeing did not reply to queries on this issue in time for publication.

GOES-13, the first of a three-satellite series, is parked 22,000 mi. over the Eastern U.S. and is designed to help with weather forecasting; it is instrumental, for example, in predicting hurricane activity.

It apparently experienced a problem last fall that was corrected with a software upload. At that time, GOES-14 was shifted from a safe parking orbit, reserved for spares, into an operational position to pick up the slack. It was later moved back once the primary GOES-13 was remedied.

NOAA officials have not yet opted to again move GOES-14 from its orbit at 105 deg. west. GOES-13 is at 75 deg. west, giving it a better ability to peer into the Eastern Atlantic. Jungbluth, however, says that for now GOES-14 can provide the necessary information about the Eastern Continental U.S. and, if needed, the agency can work with colleagues in Europe to fill in gaps in the short term.

Moving GOES-14 in and out of orbit, however, can compromise its operational life. So the GOES-13 failures could have a ripple effect on the string of successor satellites planned for this mission.

Experts at NOAA’s Command and Acquisition Data Station at Wallops Island, Va., are communicating with the spacecraft to try to figure out the problem. A government official said the attitude control issues could point to a possible problem with the star tracker." via Behind the Black, Robert Zimmerman






.