SSOC Tohban Report for Week 15 (09-Apr-2001 to 15-Apr-2001) SSOC Tohbans : Y.Suematsu,Y.Kubo,S.Akiyama KSC Tohbans : H.Takahashi,H.Isobe 0. Meeting Attendees T.Kosugi, H.Hudson, J.Khan, K.Matsuzaki,H.Ishizaki, T.Miyagoshi, Y.Suematsu, A.Takeda, Te.Watanabe ------------------------------------------------------------------------------- 1. Solar Activity The solar activity level was high last week. There occurred three X-class flares and four M-class flares as listed below. date max.time X-ray/optical NOAA region Apr 10 05:26 X2.3/3B 9415 APr 11 00:31 M1.0/? 9415 13:26 M2.3/1F 9415 Apr 12 03:04 M1.3/1N 9415 10:28 X2.0/SF 9415 Apr 15 13;50 X14/2B 9415 (from Hiraiso report and NOAA Weather Wire Service http://www.sec.noaa.gov/Data/wwire_tab.html) ------------------------------------------------------------------------------- 2. Standard Operations 2.1 SXT Table Uploads The following SXT tables were uploaded: JST Day UT Start Time Pass Table ID ========================================================== Monday 9-APR-01 12:09 3 010409 P3 ARS1 STD Tuesday 10-APR-01 07:07 1 010410 P1 ARS1 DARK Tuesday 10-APR-01 12:10 4 010410 P4 ARS1 DIFF Wednesday 11-APR-01 07:07 1 010411 P1 ARS1 STD Thursday 12-APR-01 10:31 3 010412 P3 ARS1 STD Saturday 14-APR-01 10:32 4 010413 P4 ARS1 STD ========================================================== 2.2 STT Timer Setting The STT timer set was done during pass 4 (Pass ID : 010410-0825) on Tuesday, 10-Apr-2001 (UT). The STT timer was stoped during pass 2 (Pass ID: 010414-) on Saturday, 14-Apr-2001 (UT). ------------------------------------------------------------------------------- 3. Special Operations KSC antenna was down during pass1 through pass2 of 13 Apr and command uplink was not possible in these passes. Therefore, OP uplink was done in pass3. ------------------------------------------------------------------------------- 4. Errors and Problems 4.1 SXT Errors Bit-map error was found at pass 1: 010411-0515 (11 Apr) and recovered by Yobi-C command in the same pass. Bit-map error was found at pass 1: 010413-0411 (13 Apr) and recovered by Yobi-C command in the pass 3: 010413-0618 (13 Apr). 4.2 DP Errors None. 4.3 BCS Errors None. 4.4 Day-OG issue timing problem OP DAY-OG was issued before Dawn (sun-presence signal) at 12:52:27, Apr. 12 (UT), after pass4 and YOHKOH was in the night mode till the next contact of pass5. This incorrect timing was because that the OP was created using the previous week orbital data. Thanks to recent high solar activity, YOHKOH orbit is changing very rapidly. Therefore, Toban should use the latest orbital data, in creating OP. ------------------------------------------------------------------------------- 5. NASA Station Schedule 5.1 Contact Pass Cancellations/Additions The following schedule changes occurred: =================================================== Week Schedule Changes =================================================== Real-Time 15 3 cancellations Final 16 1 cancellation Preliminary 17 0 cancellation Strawman 18 33 cancellations =================================================== 5.2 Contacts this week and next (see 8.12): Week Wallops Santiago Goldstone Canberra Madrid NASA Japan 15 28 1 11 0 6 46 26 16 25 3 5 12 0 45 26 5.3 Data Transmission from NASA Ground Stations ----(Copied from /home/flare1/yohkoh/dsn_corrupt/2001/01_15)---- 078 16 1535 missing data requested 26-Mar no response requested 02-Apr no response requested 06-Apr Closed/ same data 084 66 0410 missing data requested 26-Mar no response requested 02-Apr no response requested 06-Apr Closed/ correct data 085 80 0900 corrupted tape requested 05-Apr Closed/ same data 089 82 0544 corrupted tape requested 05-Apr Closed/ same data 087 66 0052 missing data requested 11-Apr Closed / same data(16435 blocks) LOST TELEMETRY DATA WHEN USING MCP. COUNTDOWN RUN USING MCP. JUST PRIOR TO AOS, MFR INDICATION AT MCP 'MPA CTL STS DISPLAY' STARTED BLINKING IN RED, AS IT WAS IMPOSSIBLE TO SOLVE THE SITUATION. SWAPPED TO LEGACY EQUIPMENT TO CONTINUE THE SUPPORT. 087 66 0233 not received requested 11-Apr Closed / no data NO DATA WAS RECEIVED. 094 16 0906 not received requested 11-Apr Closed/ no data UNABLE TO MOVE ANT TO POINT, MCP INDICATING X-AXIS AND Y-AXIS DISABLED AND COULD NOT BE ENABLED. PERFORMED REBOOT OF MCP WITHOUT SUCCESS, THEN REBOOTED MPC-MPR WITH NO CHANGE IN STATUS. COULD NOT CLEAR PROBLEM BEFORE LOS. PERFORMED SHUTDOWN REBOOT OF MCP TO CLEAR PROBLEM AND GET ANT AXIS CONTROL. NO DATA WAS RECEIVED. 094 66 2143 missing data requested 11-Apr Closed / same data (12103blocks) ANTENNA STOPPED. ALARM: M66:367:BRAKE UNEXPECTED, ANT MODE:STOP. SELECTED ANT MODE AUTO, BUT PREDICTS INACCURACY WAS TOO HIGH TO ACHIEVE LOCK. 095 66 2145 missing data requested 11-Apr Closed / same data (12103 blocks) 093 82 0228 corrupted tape requested 11-Apr Closed/ correct data 093 82 0551 corrupted tape requested 11-Apr Closed/ correct data 093 82 0733 corrupted tape requested 11-Apr Closed/ correct data DOY-096 16 0727 - 0739: No Data No TLM due to MCP problem. DOY-098 16 0548 - 0600: No Data The "Y" axis hydroulica failed to start. Released system to the hydromechanic technicians for troubleshooting/ repair. DOY-098 16 0730 - 0741 : No Data Unable to move ant to point --- Y-axis hyd will not enable to release brake. Rebooted MCP with no change in status. Referred problem to ant hydromechs. DOY-098 66 2008 - 2019 : 18560 blocks AT BOT MFR#1 came I/L showing a S/L 0f -121 DSM. ACQ'D in a sideband/sidelobe. MCP#1 failed during C/down. Switched to MCP#2. DOY-100 16 0550 - 0602 : 13921 blocks. Late RCVR lock. Entered -10 sec time bias to finally acquire S/C. Had RCVR in-lock at 055235z and TCP1 in-lock at 055245z. DOY-101 16 0410 - 0421 : 11193 blocks. Could not acquire a strong downlink. Suspect a predict bias or offset. Enterd time bias in both directions, but signal levels were characterlatic of a sidelobe track. DOY-101 16 0552 - 0602 : 15848 blocks OPS chief reported postpass low TLM block count of 15000 blocks. There was no indication of any problem this support. RCVRS were in-lock from 055255--060227z with TCP1 in-lock from 055444 --055932z. Time bias for this support was -2 sec. Reason unknown. 094 76 0411 corrupted tape requested 13-Apr 096 74 1617 corrupted tape requested 13-Apr 097 74 1618 corrupted tape requested 13-Apr ------------------------------------------------------------------------------ 6. KSC Pass Conflicts and Schedule Yohkoh lost 6 passes due to conflicts with Akebono. Yohkoh will lose 6 passes due to conflicts with Akebono. ------------------------------------------------------------------------------ 7. Hikitsugi Items 7.1 Tohbans for Next Week SSOC Tohbans : H.Ishizaki, T.Miyagoshi KSC Tohabns : H.Isobe, H.Kozu 7.2 STT Timer Setting The STT Timer Setting is due on Friday, 20-Apr-2001 (JST). The STT will be shut down for the period of 14-Apr-2001 to 20-Apr-2001 because of the eclipse of Canopus. 7.3 Please continue to take STT MAP every day (see 8.10). 7.4 Holiday Schedule (KSC 34m antenna TEL: 0994-67-3152) The next holiday is 22-Apr-2001 (JST). The 34m-anntena operation is scheduled for Pass 2 (11:12-11:25 JST) and Pass 5 (16:17-16:30 JST). 7.5 OP preparation and OP Start time Please use the latest orbit data in creating OP. Because of high solar activity, YOHKOH orbit changes quickly. If KSC Toban finds large time difference between the predicted and actual event time (10 deg. elevation, max elevation, etc.; ask KSC antenna staff which is better), please report SSOC and try to reflect the time difference to the OP START time. ------------------------------------------------------------------------------ 8. Unchanged Hikitsugi Items from Previous Weeks: 8.1 Weekend Terminators If possible, please schedule terminator opportunities on any weekend table (i.e., if room permits). 8.2 Software Problems PR_GEV with /hc keyword produces a temporary output file but does not print it at the printer. 8.3 OP_FIRST_GUESS Problem (1)(1999-w38, 1999-w45) In a situation with two KSC cancellations on each of two days (a rare condition) the BDR optimization feature of OP_FIRST_GUESS crashed. After experimentation, we found that it ran OK without the final cancellation request (two the first day, but just the first one on the second day). The second one then had to be removed manually. Records of the problem were forwarded to Lemen-san, but no answer had arrived at the time of writing. (2)(1999-w46, 1999-w45) During the preparation of 991109-1238 OP, 991110-1135 OP and 991111-1032 OP OP_FIRST_GUESS crashed with the message "OP_START_END: problem with detection of LOS/AOS/DSN Repro events". This problem was solved by changing OP_FIRST_GUESS options: choose optimization 1 rather than 2. (3)(2001-w06) OP_FIRST_GUESS frequently got confused about start times, trying to read weekly files extending forward years from the present. Re-tries eventually worked. 8.4 Keeping Wallops Contacts (1999-w42, 1999-w45) This is not a new policy, but to emphasize (paraphrased from e-mail from Hugh Hudson): We should keep all valid Wallops passes, independent of day/night status, in order to maximize our Wallops use and minimize our DSN use. NASA won't give us many DSN passes anyway, so if we select a Goldstone pass in preference to a Wallops one, we'll normally just lose both. Another reason is that CANCEL_DSN software needs some repair, since it seems to replace the DSS identifier WGS with 0. This is likely to cause confusion, but of course if we don't cancel Wallops passes we won't have this problem often. 8.5 DSN Pass Additions (2000-w20; modified 2001-w10) *** Don't forget to request pass additions! *** Yohkoh loses DSN passes as follows: (1) Canceled because Santiago is unavailable (Actually it is now available until end of 2000) (2) Canceled by the SSOC tohbans (3) Deleted by DSN The Tohbans SHOULD COMPARE the STRAWMAN, PRELIMINARY and FINAL schedules. -------------- for each week to see if some of the passes lost by case (4) could be replaced by ones from case (3). This means it may be possible to request pass additions for the PRELIMINARY and FINAL week schedules from the (case (3)) STRAWMAN cancellations. (The cancellations by Seko will generally be marked in red ink, and those by SSOC by pencil: Only request additions from the penciled cancellations). The routine to use is ADD_DSN: e.g., IDL> ADD_DSN, 28, /prelim and IDL> ADD_DSN, 29, /final Decide on the complete list of passes to be added and select them like CANCEL_DSN. Then ftp and email the appropriate file. 8.6 34m ANT Operation (2000-w33, 20001-w12) 34m Operation will be done only on Sunday (=Yohkoh holiday) for up to 2 or 3 passes. There will be no 34m OP to compensate for the lost pass due to the conflict with the other satellites. For further details, please ask Kosugi-san. Note that 34m operation requires more CE slots in OP table than DSN operation does. Weekend OP cannot accomodate many 34m passes without sacrificing even more DSN passes. Also, max elevation of the 34 m antenna should be checked carefully using Weekly Visible Diagram (do not trust op_first_guess nor AOSLOS listing). Try to avoid zenith passes ( Max. El. >76 degree) in planning. However, do not try to change the already fixed schedule just because the pass chosen turns out to be a zenith pass. There's no problem using the zenith pass with extra few op commands. (2001-w12) 8.7 Weekend DSN passes (2000-w49) We used to schedule 12 DSN passes during the weekend, but now we have two passes with the KSC 34m antenna. So only 9 or 10 DSN passes should be scheduled for the weekend. Please be sure to cancel extra passes as early as possible. 8.8 DSN Max Elevation DSN max elevation must be higher than the following value: Contact Max El.(degrees) Madrid 10.0 (2000-w45) Santiago 13.5 (2000-w44) Wallops 6.5 Others 7.0 8.9 OP and SXT Table Transfers Trouble (2000-w34) OP and SXT tables can not be transferred to KSC correctly when the MS computer at ISAS is in Initial Program Load(IPL). ASCA and HALCA groups operate the satellite from ISAS. We must not transfer OP and SXT tables in the following periods: "An hour before the beginning of HALCA/ASCA contact and an hour after the end of HALCA contact." As for IPL of MS computer at KSC, operators confirm if new OP and SXT tables come to MS computer at ISAS after the IPL. 8.10 STT MAP operation in OP (2000-w42, revised at 2000-w53, 2001-w08) If possible, please schedule the STT MAP operation just before the 1st KSC Pass on next day. The OP commands to be insrted in OP are as follows; OG-030(DEC) CMPN OBS ON OG-035(DEC) STT EVENT OFF ; 1 step after CMPN OBS ON OG-117(DEC) STT MAP START ; 1 step after STT EVENT OFF OG-118(DEC) STT MAP END ; 5 min (10steps) after STT MAP START OG-036(DEC) STT EVENT ON ; 1 step after STT MAP END OG-031(DEC) CMPN OBS OFF ; 1 step after STT EVENT ON Plese insert these command manually in OP schedule. The timing of these commands must be assigned around the mid-time of Canopus tracking window (note that the Canopus tracking does not work normally in this window). It is prefer that the command work during the night period of the satellite. The Canopus tracking window appears on the AOSLOSGD plots as a dotted line. It is preferable to schedule the 10 steps contiguously (as shown, avoiding mode switches). 8.11 Bug-fix Report about the Attitude Determination Software (ADS) at 200-w53 Related with the Y2K problem, a software bug was found in the attitude detection software. The problem occured in the procedure to search the orbital element file. In the program including the bug, the attitude of the Yohkoh satellite was calculated using the latest orbital elements in DASD or Serius database, while it must be done using the elements of the day nearest to the observation date. This buf has been fixed now. This bug causes the large attitude error when the observation date and the calculation date of the attitude are largely different. From 2000 Jan. to 2000 Sep., there are 10 candidates with the attitude error greater than one minutes of arc, which are as follows (obs. date); 27-Apr-2000, 28-Apr-2000, 13-Sep-2000, 14-Sep-2000, 7-Jan-2000, 11-Sep-2000, 9-Mar-2000, 8-Jan-2000, 28-Sep-2000, 12-Sep-2000. Re-calculation of the attitude is scheduled to these 10 cases. 8.12 print_contact (2001-w07) It's helpful to see the actual statistics of the DSN/Wallops station passes. The program "PRINT_CONTACTS" does this for inclusion in the weekly report, e.g. IDL> print_contacts,[6,7] lists the passes for weeks 6 and 7. [end of report]