Comment by Neywiny
10 hours ago
I work near space but not in space. I'm not sure I understand your process here. I see 2 possibilities: 1. You bought something the manufacturer spec lied about. While true we often validate specs, our terrestrial stuff is a lot cheaper so we can afford the spares. That said, if we buy something that doesn't meet the spec, you best believe we're taking the actions necessary. 2. This was built or designed inhouse, and the requirements didn't flow down correctly. That's also not great.
To be honest, postmortems (especially from startups) toe a fine line of scaring off investors, and this write-up seems a bit too glaze-y. I'm very happy for you that so much worked so effortlessly post launch, but that's more a success story than a postmortem. I'd like to see more of the root cause analysis for the issue, both technically and programmatically.
To be certain, if you're in the trenches of this anomaly investigation you'll get the full root cause and corrective action presentation, but that's not what this post is for.
You're correct on 1, we ended up hitting an edge case in their spec that they hadn't adequately tested to and the upper level management and engineering leadership were swift to accept the fault and implement fixes with us going forward.
From a SE perspective, as a "COTS" product, we had spec'd correctly to them, they accepted our requirements and then executed each unit's acceptance test plan (aka lower level than first unit quals or life tests where this should have been caught) on the ground without anything amiss. We ran through our nominal and off nominal cases at the higher level of assembly, but not for a duration that caught this on the ground. It wasn't until we were at extended operation on orbit the issues began.
Sadly like you state, space isn't like on the ground, you can't buy spares or replace things that fault, even for a true high volume COTS product that might slip through the acceptance testing.
> We ran through our nominal and off nominal cases at the higher level of assembly, but not for a duration that caught this on the ground. It wasn't until we were at extended operation on orbit the issues began.
So I think that's a great answer. It's all about risk mitigation and tolerance. Your test tested if the part work to a reasonable and hopefully calculated level. It's good that the suppliers' management accepted fault, too. It's a lot harder when they don't but honestly in the professional world I've found that to be much rarer than consumer.
To me, and I'm not an investor, and probably not your target audience, those 3 short paragraphs told me a lot more in a positive way than I expected. I don't think it would be out of place to put it in the post. Honestly as is I thought this was your guys' fault for myriad reasons. Now I'm flipped the other way. Of course it's still your problem even though it's not your fault. Or, maybe, you do claim some blame for the worst case analysis not shaking out that edge case. Either way I feel much less like you guys just went to the hardware store, bought some random lube, packed the bearing, and shipped it thinking you'll figure it out on the next launch (which is sadly the fast and loose reputation new space is starting to get).