The latest shuttle launch was previously delayed by a fuel sensor failure. The sensors are obviously important, and you don’t want to launch when one isn’t working. Or do you?
Without the benefit of examining the numbers, I am going to sit safely here on my sideline and second guess the engineers at NASA.
Ok, assume you’re working for NASA, a well known governmental agency. Your goal is to put shuttles into space. Cost is not really a consideration. So somewhere you need to balance reliability with mass. Impeccable reliability and low mass will likely go hand-in-hand.
So, back to these fuel sensors. There are four them. But they only need two. So the system has increased redundancy, complexity, mass, and partial rate of failure. It seems they should remove the 4th sensor altogether, apply the mass to the remaining 3 making them all more robust.
Just because you’re a rocket scientist doesn’t mean that you can’t “keep it simple, Stupid!”
So actually, I’d probably argue for scrapping the shuttle program altogether. When comparing it to it’s original design goals, it’s a horrible failure. A cheap, reusable craft with quick turnaround between flights was a great goal. The space shuttle is only moderately successful at being reusable, and it performs even worse in the other two categories. We probably should have cut our losses after that last tragedy and started over again.
