All,

    We had a couple issues during the perigee contacts. The inertial maneuver was successful.

During the contact on 11/15/22 @00:30 USHI01 it was noted that the ACE went thru a hard reset. The reset occurred on 11/14/22 @14:18:00. The ACE was performing nominally during the contact. Normally for a soft reset we see that the ACE uptime and the thruster on time counters have reset to zero. This time we also saw that and the static z rate had reset to a default value of 4.159. It should have been set to 4.169. Since we had completed the apogee maneuver and it was an inertial maneuver the tlm point “Point inertial” should have been set to 1 instead it was set to 0. The point “Point at sun” should have been set to false and it was at true. Also, the KF_input_Selsource was set to GND_CMD vs. STA_PCT_Valid. The star tracker status flags and the estimator status flags were set to disable. We executed standing CAR #1004 “ACE reset recovery” to re-enable the ACE FDC status flags. We also reset the static z rate and reset the KF Input to STA_PCT_Valid. Post pass playback verified that the spacecraft values prior to the reset were nominal and the apogee inertial maneuver was successful.

 

   The USHI02 contact on 11/16/22 @19:00 started off with a negative acquisition. We changed the data rate from 160k down to 2k and the SSC NMC was able to see a downlink. Since they saw an Eb/No that was 12 db. Which was very low for a perigee contact. The NMC decided to configure USHI01 to shadow us. On the USHI01 station the Eb/No was ~30db. This is what they should be seeing during a perigee contact @2k. We requested that they reconfigure our connections to command and receive data thru USHI01. Once command was established we were able to set the downlink to 320k and dump the SSR. During troubleshooting, the issue the NMC found was that the configuration file for the down converter was incorrect. Once they configured it correctly, they saw that the receive levels for both stations were within 1 db of each other. The SSR Dump for Orbit 587 was successful with zero errors.    

 

Tasks Accomplished:

SSR Dump -> Dump New

CAR #1004 ACE Reset Recovery

CAR # 1277 Orbit 589 ATS upload

  IBEX_2022_329_o0589a_v001 96 Commands

Reset Master Timer

Set Static Z rate

Set Kalman filter to STA Percent Valid

Dumped FC Back Orbit Data

 

 

Results from the Perigee Inertial Maneuver:

Q1 0.78891100 ActNor.EstInrToBdy[0]

Q2 -0.17835100 ActNor.EstInrToBdy[1]

Q3 -0.28080700 ActNor.EstInrToBdy[2]

Q4 0.51667900 ActNor.EstInrToBdy[3]

     

GPS sec 1352613660 ActNor.EstTime

     

UTC time 11/16/2022 06:00:46 output

MPS Diff 0.621 deg

MPS Cmd Vector X -0.624991000

MPS Cmd Vector Y -0.712615000

MPS Cmd Vector Z -0.318695000

CSS Angle TLM 2.21

CSS Sun-Pointing Angle 4.42

  12 Nov 22@02:00:00

CSS Angle TLM 1.07865

CSS Sun-Pointing Angle 2.1573

  16 Nov 22@06:00:00

Pre-Burn   

Thruster 1 0 15 Nov 22@00:30:00

Thruster 2 0

Thruster 3 0

Thruster 4 0

Post-Burn  

Thruster 1 288 16 Nov 22@06:00:00

Thruster 2 288

Thruster 3 336

Thruster 4 336

Number of Pulses  

Thruster 1 288

Thruster 2 288

Thruster 3 336

Thruster 4 336

Thruster Pairs  

Thruster 1 & 2 576

Thruster 3 & 4 672