Busy month for ADCO on ISS

It’s always busy on the ISS – there is always at least some kind of exciting science or important maintenance activity keeping one particular set of flight controllers or another working hard. But August has been particularly busy for those of us concerned with visiting vehicle traffic and ISS attitude control. Pretty much anytime anything is coming or going, something comes inside or goes outside (spacewalks, for instance), or you need to test some thrusters or purge some fuel lines, you can bet ADCO is doing something with the ISS Motion Control System to keep the spacecraft nice and stable. Our whole job can be summed up as trying to prevent a LOAC (pronounced “low-ack”), or loss of attitude control.

The period from August 10th to September 11th is a busy final month of Expedition 44 ripe with LOAC-prone activities. Two cosmonauts crawled outside for a spacewalk back on August 10th, which includes an airlock depress that has LOAC potential. The very next day the prop lines for Progress 58 were purged overboard in preparation for the undocking on the 14th. All three of those events required special procedures to keep the station straight and level.

Next week, things are busy again with HTV5 capture and install on Monday, a thruster test for Soyuz 42 on Wednesday morning, and then the Soyuz 42 relocate on Friday, to make room for Soyuz 44 docking on September 2nd. The Expedition ends on September 11th when Soyuz 42 undocks and lands in Kazakhstan.

All of these “complex ops” (to use our common jargon) means extra team members beyond the standard skeleton crew have to staff the consoles in the control centers. The Russian visiting vehicle events can present an extra challenge for the staffing schedule as they often happen in the middle of the night, which is when the ISS tends to pass over the Russian communication ground sites. In ADCO, one of the ways that we try to ease the scheduling complexity is to have a standard rotation of “operators” on the schedule and then if some complex ops fall on a particular day, a “specialist” will volunteer to come in and help out. Generally, we like a two-person team with a front-room and a back-room flight controller, in case anything tricky or unexpected happens.

As a specialist myself, I get excited when the weekly email goes out asking for volunteers for any upcoming complex ops. Working a complex ops shift often means getting to interact with your flight control team colleagues and sending commands to the spacecraft itself. By comparison, a “quiescent” shift for ADCO involves a whole lot of not commanding to the spacecraft, hoping nothing breaks on you, not really talking to anyone, and working on the planning paperwork for upcoming complex ops. It’s of course always awesome to get to work in the mission control center on any shift, but being a part of a team to do something really exciting like dock a new spacecraft is a special privilege.

So, what did I volunteer for then? Well, it actually turns out that I’ll be helping out with all three of the complex ops next week. I’ll be the second shift for the HTV rendezvous (I take over after they’ve already grabbed it but still have to berth it) and then I’ll come back for the Soyuz thruster test and the then the Soyuz relocate itself. I actually keep a list at my desk of which types of events I have worked. Soyuz relocation events are rare and far between, so this is my first opportunity to be a part of one! I actually spent some time today sending myself calendar invites called “sleep” for next week, to make sure I get enough rest in between shifts. I actually didn’t think that was that weird until I wrote it just now. Anyway, while everyone else is looking forward to the weekend, I’m actually looking forward to Monday because that’s when the fun begins!

If you are interested in following along with next week’s events, check out NASA’s TV schedule. There should be live coverage of the HTV capture and then the Soyuz relocation.

August 20, 2015 8:52 pm

Leave a Reply