I had doubted they would make it. And what about the ECO Sensors? This is all I could find mentioned about them:
The final test of the engine cutoff sensors has been completed. All of the sensors continue to operate normally in today's countdown.
The concerns I had about this whole problem with the ECO sensors was that they were showing to be operating sometimes normally, other times not so normally. No one could make heads or tails of what was going on. Theories on grounding were a potential cause, but EM interference from newly installed heaters were also mentioned.
The concern I had was that without a clear identifiable cause for the problem you really don't know what's going on. And by the sounds of it, not a single sensor failed today. If the grounding was really the problem, and we really understand that problem, they should have seen a failure in at least one sensor where the wiring was switched to. Basically, the way I'm understanding it, they were moving the wiring from the sensor that failed, to another sensor, so that they could see if the problem would follow the wiring.
I read Rand Simberg's latest this morning and shook my head...
Now, here's the deal. This is a tough problem to troubleshoot, but the prevailing theory seems to be bad wiring. So they've come up with a clever solution. They're going to swap the wiring between the sensor that failed, and another one. Now, either all of the sensors will check out fine tomorrow, in which case they shrug their shoulders and launch, per the new, stricter rules. Or else, they'll see a failure, except it will be on the sensor that they changed, which will mean that the wiring was the problem, and they now understand the issue. Under those circumstances, they can waive the rules (and this won't be a "last-minute decision," as I heard it reported this morning--it will be a well-thought-out one that they've been thinking about for days) to launch knowing that they still have fail-safe redundancy.
Except that if they don't see a failure, which they didn't, it means they don't understand the problem at all. If you don't understand the problem are you just going to forget about it when it doesn't surface at inconvenient times?
Are we just going to chalk this one up as a reasonable risk to take? They don't understand the problem, so how can they truly know the risks? No one is asking for NASA never to launch the Shuttle again, but we are asking legitimate questions.
Simberg knows a lot more about this than I do, but I just can't understand where he's coming from. He's suggesting that the safety rules in this case are too high... I'm suggesting that regardless they should at least understand what the crap is going on before they flip the switch. NASA wouldn't have had to spend the extra money now, if it had just listened to NASA engineers back in April, when they asked for another fueling test to verify that the fix they made back then on the ECO sensors worked.
What now? Well I hope they don't forget about this, and figure it out for the next flight.
And I guess the proof is a proof - the flight was a complete success. No kaboom. That's something that pretty much shuts me up and vilifies Simberg.
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