Shuttle Flight Tanked

So says Robot Guy. And So confirms Reuters. The flight has been delayed a week:

Discovery was fueled and ready with the astronauts strapped in their seats for a planned launch at 3:51 p.m. EDT (1951 GMT) when the problem with the liquid hydrogen fuel sensor occurred at 1:32 p.m. (1732 GMT). The sensor is one of four that detects fuel levels when the tank is nearly empty.
In the event of a launch, a sensor malfunction could conceivably cause the main engines to switch off prematurely

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Oh really? I remember a previous post I made about some hydrogen fuel sensors... But we were told that that problem was a-ok:

As for the hydrogen sensors, which operated normally the second time around, engineers now believe whatever caused problems during the first tanking test was corrected during extensive post-test troubleshooting.
...
NASA managers decided June 6 to forego a third tanking test, saying they were confident the new tank would behave normally during Discovery's countdown. Even though the hydrogen pressurization system begins operating just two minutes before liftoff, the countdown can be safely stopped if any problems develop.

I'm thinking those are the same sensors. In which case that would mean that those naysayer Engineers that called for another fueling test have just been proven right. Unfortunately it happened on the launch pad.

The whole concern was that NASA Engineers were not sure if those sensor malfunctions were a cause of the particular External Tank they were using, or one of the modified designs they made to reduce ice build ups. The idea was swap tanks and test it again. If the problem was still there - that leaves the latter.

The third fueling test was never done. And now they had them fail on the launchpad. I guess Murphy's Law has just been proven right again. Now they know that the problem lies in the modifications they made. I bet a lot of Engineers are freaking out right now - because they are going to have to sort through the modifications to test which one is the problem. At least that's what I'm guessing. I'll have to read more to be more confident.

It's hard not to believe in divine providence here: those sensors could have easily malfunctioned in flight while still being normal on the pad. They were said to be working "intermittently." In which case I don't know if they still have the capability to verify the sensor's readings... If they don't, that means you have to believe something was watching out for those astronauts.