NOAA Office of Satellite and Product Operations

NOAA 14 ADACS Subsystem Summary

Component Status:

Component
Description
Status
ESAEarth Sensor AssemblyGreen
GYRO 1Gyroscopic Rate Measuring Device #1 -Yaw (X)Green
GYRO 2Gyroscopic Rate Measuring Device #2 -Roll (Y)Green
GYRO 3Gyroscopic Rate Measuring Device #3 -Pitch (Z)Green
GYRO 4Gyroscopic Rate Measuring Device #4 -Skew (S)Green
PTC 2APitch Torque Coil 2AGreen
RWA SSkew Reaction Wheel AssemblyGreen
RWA XX-axis Reaction Wheel AssemblyGreen
RWA YY-axis Reaction Wheel AssemblyGreen
RWA ZZ-axis Reaction Wheel AssemblyGreen
RYTC 1ARoll-Yaw Torque Coil 1AGreen
RYTC 1BRoll-Yaw Torque Coil 1bGreen
RYTC 2ARoll-Yaw Torque Coil 2AGreen
RYTC 2BRoll-Yaw Torque Coil 2BGreen
SSASun Sensor AssemblyGreen

Subsystem History:

Date Time Component Description
05/18/200719:15:00 Disables macro 11
05/17/200714:30:00 Command attitude control back to nominal mode. To evaluate new ESA Biases.
05/15/200714:50:00ESAUploaded ESA biases from Area of Triangle Method.
03/26/200718:51:00 NOAA14 Coil Switch due to YGC Mode, just like the 2/2/2007 event.
02/07/200719:00:00 RY coil switching enable
02/07/200719:00:00 RY coil to primary
02/02/200700:00:00RYTC 1ANOAA14 continues to be in YGC mode. The NOAA-14 had coil switching event on 2 Feb 2007. There was an ESA quadrant switching event coincident with exiting a momentum unloading region. The event occurred during a 19 hour data gap, so the exact time is unknown, but after examining the GEODAT for that period and found two times when an ESA quad switching event coincides with the end of an unloading region. It is believed that the coil switch occurred at one of these times. It works like this: At the end of an unloading region the magnetic momentum unloading software performs a test, which is simply a check of the RWA speed. The limit for NOAA-14 is 3280 RPM. If this limit is exceeded the coil will be switched to backup and further coil switching will be inhibited. Since the spacecraft is operating in YGC the transients on the yaw RWA during ESA quadrant switching are much larger than in the nominal mode. The peak RPM often exceeds 3300. This is enough to trigger a coil switch if it happens at the right time. It is planned to be commanded back to the primary side on 7 Feb at 19:02z
12/01/200618:36:00 Spacecraft attitude control mode autonomously switched to YGC once again at the instant that STX-1 was turned on.
11/30/200618:50:00 Command attitude control back to nominal mode.
11/19/200614:34:00 Spacecraft attitude control mode autonomously switched to YGC once again (the fourth time in just over a month) at the instant that STX-1 was turned on.
11/15/200618:45:00 Command attitude control back to nominal mode.
11/13/200622:35:00 Spacecraft attitude control mode autonomously switched to YGC once again (the third time in just over a month) at the instant that STX-1 was turned on.
10/27/200619:30:00 Command attitude control back to nominal mode.
10/21/200605:19:00 Spacecraft attitude control mode autonomously switched to YGC. Telemetry verification of cause not available. Earth sensor glint suspected.
10/11/200619:35:00 Command attitude control back to nominal mode.
10/08/200613:36:00 Spacecraft attitude control mode autonomously switched to YGC. Telemetry verification of cause not available. Earth sensor glint suspected.
10/04/200617:51:00RWA STurn off Skew wheel power
10/04/200617:50:00RWA XTurn on orthoganal (X) reaction wheel.
10/04/200614:30:00 Command Rgyro to monitor mode and put the spacecraft back in YGC attitude control mode.
09/29/200603:15:00 After commanding RGyro passive mode, spacecraft dropped into GYE (gyroless) because of excessive yaw errors (over 7 degs).
09/29/200601:30:00 Spacecraft in YGC attitude control mode at AOS.
09/28/200622:30:00 After gas enable operation completed spacecraft went into SEARCH attitude control mode.
09/28/200615:05:00RWA XMajor spacecraft attitude perturbation saturated X-wheel causing it to be autonomous swapped out for Skew wheel.
09/28/200615:04:00 Major spacecraft attitude perturbation resulted in autonomous IMU Logic board switch.
08/16/200620:01:00 Restored normal thruster unload levels, disables auto-gas unload and thrusters
08/16/200620:00:00 Restored spacecraft to nominal attitude control mode (from YGC).
08/10/200616:05:00 Pitch Over Maneuver completed nominally. Pointed MSU and other payloads into deep space by halting the spacecrafts constant pitch rate and holding an inertial attitude for one orbit (16:05z-17:51z) then returning to constant rate. Spacecraft ended maneuver in YGC attitude mode.
05/04/200614:00:00RWA XPrerequsite test for future "pitch over tilt test". Increased momentum unload threshold on all RWheels to 6000 RPM to determine the effects of a full orbit with no momentum unloading. Impact on wheels minimal. Returned to normal configuration one orbit later.
09/21/200117:40:00 Commanded ADACS back to nominal mode.
12/08/199600:00:00 Spacecraft automonously commanded ADACS to Yaw Gyro Compassing.
04/19/199500:00:00ESAESA scale factor & bias adjusted for lens fogging anomaly
04/04/199500:00:00ESAQuad 3 disabled due to lens fogging
03/16/199500:00:00ESAQuad 3 s counts biased and quad enabled due to lens fogging
03/14/199500:00:00ESAQuad 3 disabled due to lens fogging
02/28/199500:00:00ESAS limit increased for quad 3 enabled due to lens fogging
02/25/199500:00:00ESADisabled quad 3 due to lens fogging
12/30/199410:36:00RWA YOn Orbit
12/30/199410:36:00GYRO 1On Orbit
12/30/199410:36:00GYRO 2On Orbit
12/30/199410:36:00GYRO 3On Orbit
12/30/199410:36:00IMUOn Orbit
12/30/199410:36:00PTC 1AOn Orbit
12/30/199410:36:00PTC 1BOn Orbit
12/30/199410:36:00PTC 2BOn Orbit
12/30/199410:36:00PTC 2AOn Orbit
12/30/199410:36:00RWA XOn Orbit
12/30/199410:36:00ESAOn Orbit
12/30/199410:36:00RWA ZOn Orbit
12/30/199410:36:00RYTC 1AOn Orbit
12/30/199410:36:00RYTC 1BOn Orbit
12/30/199410:36:00RYTC 2AOn Orbit
12/30/199410:36:00RYTC 2BOn Orbit
12/30/199410:36:00SSAOn Orbit
12/30/199410:36:00GYRO 4On Orbit
12/30/199410:36:00RWA SOn Orbit