2009-07-17

Spirit Sol 191

"Here, smell this," says Julie. She's holding out an egg sandwich. "Does this smell funny?" It smells fine to me, but she's looking at it like she's not sure which of them is going to bite the other. I have visions of Julie running to the bathroom, incapacitated, just before the CAM. I volunteer to go get her another sandwich.

I have plenty of time to do this. John is struggling with a complex and lengthy touch-and-go. The IDD part wouldn't be especially complicated, but the target is hard to reach without running into one joint limit or another, so he has to work out an alternative, which takes yet more care and time. This, with the constant stream of interruptions that are the normal part of the RP-1 job, is quickly frustrating him. I gently try to persuade him to worry about either the IDD or the drive sequence and let me worry about the other, but he's too irritable to give up.

During the nominal mission, when our roles were reversed, John would do something when I got like this. He'd just quietly say, "This is so cool ...." It was enough to remind me why I'd chosen the job -- a remarkably effective tactic.

So I sit back and say, quietly, "This is so cool ...." He laughs and looks more at ease.

I let him keep working on it. Larry Soderblom's talking to several listeners about the composition of the sparkly stuff we exposed when we drove over it a couple of weeks ago. He refers to it as "iron sulfite and some crap," which provokes laughter.

"Crap would be good," I point out. "At least it would be a sign of life."

"You know," muses Scott Doudrick, "I'm starting to think we're not going to find that trilobite after all."

John finishes the sequences to his satisfaction -- we're running only a couple of hours late -- and hands over to me. It's one of the most complex sequences ever, with over 450 commands, and even though John did excellent work getting it into shape, I still have a lot to do.

We're very late when the CAM ends -- almost three hours behind schedule -- and it's a Friday, and everybody wants to go home. This being that kind of day, they notice a problem right at the end. We have a rule: no IDD movement can take place between 8.5 and 10.5 minutes after the rover wakes up. This strange restriction is a workaround for a known bug in the flight software; there's a vulnerable period where the flight software could crash and forget the position of the IDD, and we'd have to waste several sols recovering. But maybe we'll be completely done before the start of that window. Rick asks me to work out, as nearly as I can, the expected duration of the IDD sequence, and when I do, I figure we have only thirty seconds of margin.

"Is everybody OK with thirty seconds of margin?" he asks. Everybody wants to go home, so they're ready to buy off on it. I want to let them -- but my conscience is bothering me. I don't think it's the right thing to do.

"Yeah," I say reluctantly, "I have a problem with it."

At first they think I'm just kidding, but when they realize I'm serious, they swing into action. "Okay," Rick says, "let's get to work."

They make the needed changes and rebundle the uplink -- the fourth bundle of the day, which I initially think is some kind of record. But it's not: Marc Pack tells me the record was set earlier this week, when they generated no fewer than eight versions of the uplink before they were done. "So this is nothing," he says. "It's been a brutal week to be a TAP or RP on Spirit."

While they're doing this, I redo my calculation and realize I had made a small mistake: I had slightly undercounted the time required by the IDD sequence. The size of my mistake was thirty seconds -- just exactly enough time to have pushed us into the vulnerable window. I tell Rick this, and he says, "Good thing you spoke up!"

It is a good thing I spoke up. Better yet is that Rick asked whether anybody had a concern, and that the rest of the team took my concern seriously, without even a complaint, even though I'm not sure I could have defended it at the moment I raised it. It's late, and it's Friday, and they all want to go home. But even more, they want to do the right thing.

This is a hell of a team.

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