Date |
Time |
Component |
Description |
03/25/2006 | 19:36:00 | GYRO 2 | N16 Gyro-2 spin motor current surged 7 mAmps but returned to its nominal 64 mAmps within 8 minutes. TCA voltage increased with spin motor current. IMU block temp and all other ADACS components not affected. |
03/16/2006 | 20:14:00 | | IMU logic backup function inhibit |
03/16/2006 | 20:13:00 | | IMU logic backup function inhibit |
03/16/2006 | 20:10:00 | GYRO 2 | To proactively prevent gyro-2 from stalling, uploaded and activated safing macro to monitor gyro-2 spin motor current and turn off power to gyro-2 if that current exceeds 160 mAmps. Also inhibited IMU autonomous switching. |
03/13/2006 | 17:17:00 | GYRO 2 | N16 Gyro-2 spin motor current surged 10 mAmps (from 63 to 73) then retreated to a new equilibrium of 64 mAmps at 17:29z. TCA voltage increased in conjunction with spin motor current. IMU block temp and all other ADACS components apparently not affected. |
03/09/2006 | 21:43:00 | | Change N2 gas unloading trigger on pitch axis momentum to 145 in/lb/sec (from 40) absolute.CONTROL side |
03/09/2006 | 21:41:00 | | Change N2 gas unloading trigger on pitch axis momentum to 145 in/lb/sec (from 40) absolute.Non-control side |
01/17/2006 | 14:55:00 | | Increase pitch RWA bias from 1500 RPM to 2400 RPM |
12/15/2005 | 19:15:00 | RWA Z | Set pitch RWA bias to 1500 RPM to provide stiffness to attitude control in case final gyro becomes non-functional. |
12/08/2005 | 15:53:00 | | Enable IMU logic switching, control CPU |
12/08/2005 | 15:52:00 | | Enable IMU logic switching, non-control CPU |
11/17/2005 | 16:35:00 | GYRO 2 | Flight software updated to reduce gyro filter gains and clean up roll attitude signal implemented. Operation successful, objective achieved. |
11/08/2005 | 21:40:00 | | Update to MODE software module to change Gyro 1 on command pulse to a Gyro 2 on command pulse |
10/25/2005 | 00:30:00 | | Command non control side to Reduced Gyro attitude control mode. |
10/24/2005 | 22:55:00 | | N16 attitude control now running in reduced gyro (RGYRO) mode (estimated Y-axis/roll) and is expected to remain that way for the remainder of the mission. IMU switch capability remains disabled pending FSW alterations. |
10/24/2005 | 22:50:00 | GYRO 1 | Gyro-1 "slipped a pole" at 15:00z causing an IMU logic switch which then masked RED HIGH spin motor currents on both gyro-1 and 2. Gyro-1 complete failure considered imminent. IMU-AC power supplies toggled and gyro-1 was powered off. Gyro-1 downgraded to RED status. ADACS downgraded to YELLOW status. |
10/24/2005 | 22:50:00 | GYRO 1 | Permanently power off Gyro-1 after placing spacecraft ADACS in Reduced Gyro Mode, and toggling IMU AC power supplies. |
10/24/2005 | 15:00:01 | IMU | IMU switched to Primary (from Backup which it had always been since launch) after gyro spin motor current surge. |
10/24/2005 | 15:00:00 | GYRO 1 | Gyro-1 spin motor current surged 100% above normal then quickly fell to 20% below normal (yellow low value) causing IMU switch. |
08/30/2005 | 00:31:00 | | N16 donwgraded to secondary PM spacecraft after N18 declared operational. |
10/03/2004 | 12:00:00 | ESA | ESA has momentary limit violations in the ORS+I1 and ORS+I2 channels on every orbit, direct sunlight on detector suspected. Should continue for several months. No health impact. |
06/10/2004 | 13:12:00 | GYRO 3 | Turnoff Gyro-3 power permanently. Place RGyro to MONITOR mode. |
06/09/2004 | 12:00:00 | GYRO 3 | Downgrade color status to YELLOW because of continued degradation of Gyro-3. |
07/29/2003 | 14:25:00 | GYRO 2 | Change gyro channel assignments to XA, YA, ZA from XB, YB, ZB in both OBP. Gyro #3 deselected from control loop. |
07/29/2003 | 14:25:00 | GYRO 1 | Change gyro channel assignments to XA, YA, ZA from XB, YB, ZB in both OBP. Gyro #3 deselected from control loop. |
07/29/2003 | 14:25:00 | GYRO 3 | Change gyro channel assignments to XA, YA, ZA from XB, YB, ZB in both OBP. Gyro #3 deselected from control loop. |
05/30/2003 | 17:00:00 | GYRO 2 | change in counts and spin motor current characterstics |
05/30/2003 | 17:00:00 | GYRO 3 | change in counts and spin motor current characteristics |
10/10/2001 | 17:20:00 | RWA X | Commanded back to XYZ wheel set from SYZ |
10/09/2001 | 21:03:00 | | Commanded ADACS back to nominal mode from YGC |
10/09/2001 | 15:12:51 | RWA X | Spacecraft swapped from X to S reaction wheel due to 24 hour pointing test |
10/09/2001 | 12:44:00 | | Forced YGC mode for 24 hour pointing test |
09/21/2000 | 10:56:00 | GYRO 2 | On Orbit |
09/21/2000 | 10:56:00 | PTC 2B | On Orbit |
09/21/2000 | 10:56:00 | PTC 1B | On Orbit |
09/21/2000 | 10:56:00 | PTC 1A | On Orbit |
09/21/2000 | 10:56:00 | PTC 2A | On Orbit |
09/21/2000 | 10:56:00 | GYRO 3 | On Orbit |
09/21/2000 | 10:56:00 | RYTC 1A | On Orbit |
09/21/2000 | 10:56:00 | GYRO 1 | On Orbit |
09/21/2000 | 10:56:00 | IMU | On Orbit |
09/21/2000 | 10:56:00 | RWA S | On Orbit |
09/21/2000 | 10:56:00 | RWA X | On Orbit |
09/21/2000 | 10:56:00 | RWA Z | On Orbit |
09/21/2000 | 10:56:00 | RYTC 1B | On Orbit |
09/21/2000 | 10:56:00 | RYTC 2A | On Orbit |
09/21/2000 | 10:56:00 | RYTC 2B | On Orbit |
09/21/2000 | 10:56:00 | SSA | On Orbit |
09/21/2000 | 10:56:00 | ESA | On Orbit |
09/21/2000 | 10:56:00 | RWA Y | On Orbit |