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MSG PROGRAMME STATUS. Presentation to the GIST-25 meeting. MSG-1 satellite. One failure occurred in May 2006 on a “breaker” (Latch Current Limiter) inside the MSG-1 power supply subsystem. The on-going investigation does not currently point towards a design flaw.
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MSG PROGRAMME STATUS Presentation to the GIST-25 meeting
MSG-1 satellite • One failure occurred in May 2006 on a “breaker” (Latch Current Limiter) inside the MSG-1 power supply subsystem. The on-going investigation does not currently point towards a design flaw. • The consequence of this failure is that the nominal path for controlling the attitude/orbit of MSG-1 is lost, and the redundant path has to be used. • 26 September 2006 the main platform software crashed resulting in the shut down of all payloads. The failure was attributed to a single event upset (SEU) and caused no permanent damage to the platform.
MSG-2 satellite • MSG-2 satellite and system commissioning was completed in July 2006. The MSG-2 satellite has been relocated during July to 0 deg longitude. • One important issue out of the commissioning phase: “Stripes in images derived form the SEVIRI WV6.2 channel” . The reason is associated with the noise pattern of the detectors, although the noise at channel level is in spec. Met Products at pixels level are affected - no technical issues have been identified for GERB. Investigations are on-going in order to mitigate this anomaly (by ground SW and on board conditions).
MSG-2 satellite • For the time being MSG-1 remains the prime imagery spacecraft. In March 2006, the MSG-2 Image & Product Validation Review (IPVR) will take place. After this review, EUMETSAT will decide whether MSG-2 becomes the primary operational satellite. • MSG-1 & MSG-2 satellites will be kept imaging in parallel until the IPVR. • In the event that the IPVR decides that MSG-2 will become the primary operational satellite, the two satellites will be operated in parallel for a further 2 months: MSG-1 prime month 1; MSG-2 prime month 2. • Funding for GERB operations on board MSG-2 released by EUMETSAT starting from August 2006.
MSG-3 satellite • Due to unavailability of vacuum test facility, the MSG-4 AIT activities have been delayed. The MSG-3 activities have been re-started to correct issues and to complete open items raised at its Pre-Storage Review. An anomaly on the SEVIRI TM read-out has delayed the entry into storage. • Launch planning: In July 2006, the EUMETSAT Council agreed to re-plan the MSG-3 launch for January 2011 . In case of outcomes from the LCL failure investigations leading to an early launch, Delegates will be informed accordingly, and launch date will be revisited . • GERB-3 need date for satellite re-integration is January 2009 or earlier depending upon the LCL investigations. GERB-3 recalibration needs to be completed latest by end 2008.
MSG-4 satellite • Assembly of satellite (with a GERB-4 back-up) completed. Acoustic vibration test completed. MSG-4 is waiting for vacuum chamber availability. In the meantime an anomaly on the SEVIRI scan mechanism is under investigation. • EUMETSAT/ESA plan for a confidence test between GERB-4 & MSG-4. • In July 2006, the EUMETSAT Council agreed to re-plan the MSG-4 launch in the mid-2012/mid-2013 time frame. To be defined at the time of MSG-3 destorage – Jan 2013 is used for planning purpose. • GERB-4 need date for satellite integration is April 2009, as a spare for GERB-3.
GERB-1 • Commissioning of GERB-1 (on MSG-2) completed. • GERB-1 exhibits an unstable period on leaving SAFE mode that leads to a mispointing in NORMAL mode. The effect is self correcting after the mispointing event has occurred. This imposes a constraint on sun avoidance operations (in case of transition to safe mode). • A data corruption anomaly is currently under investigation. • GERB-1 is in SAFE mode for the sun avoidance season.
GERB-2 • System ARB into the in-orbit detector damage – the last check point was held in March. Final report under preparation. Review concluded that the dry lubricated bearing was the most likely cause of the anomaly, however a design change was not recommended. Operations enhancements, e.g. patch 8, were advised. • Sun avoidance patch (patch 8) incompatibility with SNOOZE mode still under investigation.
GERB-2 • On 05/10/06 GERB was switch on and configured to SAFE mode following the satellite anomaly of 26/09/06. NORMAL mode was resumed 09/10/06 and a new set of GERB detectors were found to be damaged. • An AutoSAFE had triggered around 2 hours before the satellite SAFE mode. The DSM was left in an earth view position after the satellite processor had rebooted, however the QFM was SAFE due to the earlier anomaly! In the transition to SAFE mode the QFM was rotated exposing the detector to direct sun light.
GERB-2 • A modified procedure has been suggested to prevent the transition to SAFE mode damage in the future. However had the anomaly occurred with GERB in NORMAL mode the damage would have been far worse.
GERB-3 • GERB-3 IEU is currently part of the GERB-4 Back-up integrated on MSG-4 in Cannes. Note that the timing board modifications are outstanding on this unit. • Preparations for the storage of the GERB-3 IOU are on-going. • During EMC testing using the FM3 IOU and FM4 IEU the QFM stopped rotating. Currently this is thought to be due to the change in QFM drive design going from GERB-1/2 to GERB-3/4. The new design is thought to have reduced the drive torque available.
GERB-4 Detectors: • FM#3 calibration exhibited a problem of repeatability of spectral response measurements. The major source of the anomaly has been resolved, however some refinement remains to be performed before re-start of calibration (expected by the end of July). • Proposal for detector Humidity Test received and under evaluation. • FM#2 flight spare detector will be calibrated after FM#3. • Proposal for recalibration of GERB-3 detector to be considered.
GERB-4 Quartz Filter Mechanism (QFM): • Anomaly occurred during IOU vibration resulting in the dismounting of the QFM. • A number of NRBs have been held. The QFM design appears to be sensitive to build up of component tolerance. The test vibration levels seen at instrument level exceed those applied at unit level. • A two phase approach has been proposed: i) Reassembly of the QFM to test tolerance hypothesis ii) Rebuild new QFM from best components + retest at correct levels
GERB Operations & Funding • Although MSG-2 has yet to be declared the operational satellite EUMETSAT has agreed to start funding the GERB Operations from August 2006. • The EUMETSAT operations funding will continue provided that the MSG-2 satellite remains in a fit state to be declared operational.
MSG SEU Events • AR7724 – MSG-1 RTU UP Failure (31-Dec-2002) • AR8781 – MSG-1 CACE To Fixed Beam mode (14-June-2003) • AR11202 – MSG-1 DNEL Oct 2004 (4-Oct-2004) • AR13160 - MSG-1 Battery charge ended early (27-Oct-2005) • AR14132 – MSG-2 SEVIRI SEU (3-April-2006) • AR14420 – MSG-1 LCL08 (unclear as to failure cause) (16-May-2006) • AR15039 – MSG-2 MCP IFP (unclear as to failure - but LM139 speculated) (17-Aug-2006) • AR-15234 – MSG-1 PMB SAFE mode