DSM 305 booted successfully with Serial to USB Adapter work-around. Did not have any issues in-flight.
DPR started with 'Service Mirror' light ON. Blew out both DPR and DPL.
Successful boot on both wing DSMs. 2D End Diode Voltages looked good on initial power ON.
VCSEL looks good until we get higher in altitude. It seems to get cold soaked - maybe the mirrors get frosted over - and it stops providing reliable data. The final point of reliable Dew Point from VCSEL seemed to be at 1236; 38,000 feet; LSRINT_VXL was ~1,000 cnts.
1232 - Lost both wing DSMs. After getting the DSMs back, the End Diode Voltages were low on the 25um and housekeeping did not look correct on the 10um. Cycled power on both probes which corrected all errors.
*While power was OFF on the probes, but the DSMs were running, I noticed that the RICE data looked good for a short period...until the 2D_C was powered back ON. John Cowan and I spoke about this during the flight and determined a possible cause. Cory gave me the go-ahead to turn OFF the 2D_C 10um at 1649. RICE data looks good when there is no 2D probe interference. Will troubleshoot during Maintenance Day tomorrow.
DPR data looks low and unreliable. DPL looks more reasonable. Will attend to DPR during Maintenance.
2 Comments
David Allbee
Flight Tech - D. Allbee
4Sep2019
Taxi - 1209
Takeoff - 1215
Landed - 1657
DSM 305 booted successfully with Serial to USB Adapter work-around. Did not have any issues in-flight.
DPR started with 'Service Mirror' light ON. Blew out both DPR and DPL.
Successful boot on both wing DSMs. 2D End Diode Voltages looked good on initial power ON.
VCSEL looks good until we get higher in altitude. It seems to get cold soaked - maybe the mirrors get frosted over - and it stops providing reliable data. The final point of reliable Dew Point from VCSEL seemed to be at 1236; 38,000 feet; LSRINT_VXL was ~1,000 cnts.
1232 - Lost both wing DSMs. After getting the DSMs back, the End Diode Voltages were low on the 25um and housekeeping did not look correct on the 10um. Cycled power on both probes which corrected all errors.
*While power was OFF on the probes, but the DSMs were running, I noticed that the RICE data looked good for a short period...until the 2D_C was powered back ON. John Cowan and I spoke about this during the flight and determined a possible cause. Cory gave me the go-ahead to turn OFF the 2D_C 10um at 1649. RICE data looks good when there is no 2D probe interference. Will troubleshoot during Maintenance Day tomorrow.
DPR data looks low and unreliable. DPL looks more reasonable. Will attend to DPR during Maintenance.
Kurt Zrubek
Dave,
Sent you an email concerning RICE with some thoughts.
K~