[Isocops] EXT :Re: IBEX Orbit #650 ATS Approval (June 02 - 10, 2024)

[Ken Fairchild]

Ryan,

Thanks for checking and verifying that this isn't some hidden problem.

Ken

On Tue, May 21, 2024 at 7:21 AM Tyler, Ryan S [US] (SP) <Ryan.Tyler at ngc.com>
wrote:

> Well, there *definitely* isn’t an eclipse there, since the sun and Earth
> vectors are close to 90 deg apart at that time. So I have no idea what that
> constraint check is reacting to.
>
>
>
> Looking at other cases where this constraint tripped I can see that the
> math is a bit wonky. A ~70 minute eclipse (they type where we typically set
> the long eclipse flag and everything is fine) gets reported at having 0
> W-min left (i.e., battery fully depleted). That goes up a bit for eclipses
> that are a bit shorter.
>
>
>
> Even the recent penumbral sliver of an eclipse, where the spacecraft still
> saw 98% of the sunlight so the battery never came close to discharging at
> all, got flagged by this constraint as having the battery go down to 2700
> W-min.
>
>
>
> So when this constraint shows the battery going down to 3700 W-min, a
> smaller discharge than that penumbral eclipse, I think it’s safe to say
> that the constraint violation is meaningless.
>
>
>
> *From:* Ken Fairchild <kwfairchild at gmail.com>
> *Sent:* Monday, May 20, 2024 4:02 PM
> *To:* Perry, Timothy E [US] (SP) <Timothy.Perry at ngc.com>
> *Cc:* carol.weaver at unh.edu; Chubin, Eric [US] (SP) <Eric.Chubin at ngc.com>;
> David.Heirtzler at unh.edu; ADS-IBEX at l3harris.com; IBEXOPS at gmail.com;
> isocops at lists.sr.unh.edu; Ken.Fairchild at unh.edu;
> angoldconsulting at earthlink.net; Paul.Janzen at mso.umt.edu; Tyler, Ryan S
> [US] (SP) <Ryan.Tyler at ngc.com>; Wesley, Sheral R [US] (SP) <
> Sheral.Wesley at ngc.com>; Wynn, Reese [US] (SP) <Reese.Wynn at ngc.com>; Ken
> Fairchild <kwfairchild at gmail.com>
> *Subject:* EXT :Re: IBEX Orbit #650 ATS Approval (June 02 - 10, 2024)
>
>
>
> Tim,
>
>
>
> That's a weird constraint violation.  I looked at last month's forecast
> OEFs and both versions of this month's OEF.  The outage times on 06-01 all
> track pretty closely and end shortly after 23:00 on the 1st.  I checked the
> FDG outage report and the outage times there also track well with those in
> the OEFs.  Perhaps Ryan can use his fancy tool to see if there's something
> going on that would explain this violation?
>
>
>
> Ken
>
>
>
> On Mon, May 20, 2024 at 12:22 PM Perry, Timothy E [US] (SP) <
> Timothy.Perry at ngc.com> wrote:
>
> All,
>
>    Attached are the planning files for Orbit #650. Please respond to this
> thread with comments and approvals. Approvals for the Orbit 650 ATS are
> required by 1700 , 23 May 2024.
>
>
>
>
>
> Please note the following:
>
>
>
> 1.        Battery Balancing
>
> Eclipse Flag True: 2024/06/10 21:00:00
>
> Eclipse Flag False: 2024/06/10 22:30:00
>
>
>
> 2.        Command Load Constraint Violation Report (CCVR)
>
> IBEX_2024_153_o0650a_v001.ccvr
>
> # Input files:         1
>
> #   IBEX_2024_153_o0650a_v001.scr
>
>
>
> ==========================
>
> HARD CONSTRAINT VIOLATIONS
>
> ==========================
>
> NO VIOLATIONS.
>
>
>
> ==========================
>
>         SOFT CONSTRAINT VIOLATION
>
> ==========================
>
>
>
> I saw this violation IBX-CLC-015. I looked for any small eclipses or close
> transmitter times. We never drop to zero. I can’t explain why this is
> flagging other than maybe an MPS miscalculation.
>
>
>
> IBX-CLC-015: Battery charge falls below minimum from 2024/06/02 04:43:00
> UTC -
>
>              2024/06/02 14:04:00 UTC. Lowest charge level is 3736.960000
>
>              watt-minutes during this interval.
>
> IBX-CLC-016: No command to enable spin pulse protection was found after
>
>              transition to science mode at 2024/06/02 07:01:28 UTC
>
> IBX-CLC-016: No command to enable spin pulse protection was found after
>
>              transition to science mode at 2024/06/06 00:17:58 UTC
>
>
>
> ==============
>
> OTHER MESSAGES
>
> ==============
>
> NO MESSAGES.
>
>
>
>
>
>
>
>
>
>
>
> Timothy E.Perry
>
> CRS IBEX OCO-2
>
> Mission Operations
>
> timothy.perry at ngc.com
>
> Office (703) 406-5976
>
> IBEX MOC (703)404-7470
>
> Cell (301) 606-1430
>
>
>
>
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